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Solar and heat pump hot water systems plumbers reference guide
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1. Duiusejj jooH Jeddoo WUG uu LULUQOS Y uiu UNOS gt UluuiliuooSg gt Chapter 6 System Types 73 tantaneous system ing gas ins 6 6 2 Exist The existing gas instantaneous system does not have a storage tank Therefore as with the gas storage system the solar hot water system is used as a pre heater to the existing instantaneous system which then boosts the water from the storage tank and supplies the internal fixtures Figure 6 15 shows a pre heater close coupled retrofit to an existing gas instantaneous system Figure 6 14 shows a pre heater split system retrofit to an existing gas instantaneous system Figure 6 13 Pre heater close coupled retrofit to existing gas instantaneous system installation diagram ueq u1n 1 MO0 16 OS p ejnsu WWOOE 002 4 Ajuouine e20 YIM x29u2 ylomadid 1942M pjo5 Y Buiquunid 1 u 1872M poo pos eui urep Hid yiomedid Joyem 10H i y paje nsu yiomadid Jayem paladuwa Lan Ajddns sey gt gt gt oll 5 b 5 b b P b 5 5b et Jeddoo wws 9 Ul J9 EM pJO2 BAILA JOJSUOJ JeJOS AEA uol 58 01d 1s0JJ oA eA Duueduie Jaule s our SoJnixiJ euJ8 ul o J9Jem paladua 9A E t Ld onen UOISUEQXO JaJem pop 19 eM pajesy Jejos 9AI929J 0 9 qeiins 1o1eou Jajem snoeuejuejsur Bunsix3 onen Huu 1nss id SAA UJnj89J UON onen UOITE OS O O H X El Ej K x
2. gt gt r ml o o o o o e o o o o o 5 5 5 A ll el ll el el el ll P b b P P P P 4 exoeJq Joddns k uiu WWQOS Y AUB WO Sul ATT MO soem poo sumy uoisseJduio 1019euuoo pexuelg sDuiuse JooH q U que 0 aun 1 d uJn 8J 49 eM JOH ME N gt E yue Beuols pe1unouj punoJ6 2 O UNIS J19JEM JOH di 0 9 4 uoiun Aem OM o ulu UWQOSG e A PA H1d Q lt unuuo0g gt lt ulwwwoos gt lt J 9 4iLdUH Figure 6 14 Pre heater split retrofit to existing gas instantaneous system installation diagram Compression Flashing mitinge Pewee Solar Hot Water Tank PTR Valve Existing Instantaneous Gas Unit Drain Line PA Dh PTR valve Gas Supply Line CV Tempering valve En Sensor well Tempered Water Air relief valve Ey Frost protection valve if required Tempered water pipework insulated gt gt gt gt gt gt gt U UN V UQ UN R h Kw U UU U ui gt PPP PP PP Hot water pipework insulated AA R Jaana A A gt gt Cold water pipework solar flow return insulated Solar Hot Water Pump Control Unit Drain Outlet wu RAJ f c ex y Chapter 6 System Types 75 ie ec LEAS j a hm L 4 6 6 5 Retrofit to existing electric storage tank An existing electric storage system is more suitable for retrofitting t
3. Tempering valve General Tempered water to e power outlet internal fixtures Y Y N T gt gt gt b NY Y Cold water inlet I ee a did Electric controller Before installing a heat pump system installers should consult manufacturer s instructions on minimum ventilation requirements and should also ensure that a The heat pump can be positioned in the warmest and sunniest location b There is enough empty space around the heat pump to allow adequate air flow c There is access to the system for installation and ongoing maintenance d There is at least 1 2m clearance from bedroom windows to minimise the effects of the noise generated by the heat pump 16 Chapter 2 Design Principles 2 5 6 Retrofit considerations Figure 2 6 Pre heater split system retrofit to existing storage tank Roof mounted solar collectors Existing electric or gas storage tank Solar pre heater storage tank FL P P P PbPpP P P Pb P Pb Pb Pb Pb P Pb m b 5 o r Aa V m lin n A A AAA Tempering Tempered water to valve internal fixtures P Y General power outlet PPP PP 5 ll Cold water inlet A cB Y FEET N gt Vv yo CC CCS L P P P el el ce ee ee ee ee ee ee gt pp 1 CERIS Y Y min ib A A ib lb ie Ex Electronic solar pump amp controller tan
4. C AS 5601 Gas Installations d any other applicable standards e g AS NZS 1170 Wind Loadings AS 2712 Solar and Heat Pump Water Heaters Design Construction AS 4234 Heated Water Systems Calculation of energy consumption AS NZS 4692 1 Electric water heaters Energy consumption performance and general requirements e Plumbing Code of Australia f manufacturer s recommendations g local government requirements which the installer is responsible for confirming responsibility the scope of this element will vary across state territory and local government areas h OH amp S requirements see Chapter 8 i trade and insurance licensing requirements the installer is responsible for confirming compliance with those The scope of this element will vary across state territory and local government areas j any other requirements that impact on a particular installation e g heritage listed buildings building with asbestos roofing materials streetscape planning Almost every installation will have different requirements including requirements for access to the site roof tilt materials climate level of water use or the need for additional trades people such as electricians All elements of Chapter 8 relating to OH amp S obligations should be considered prior to pre installation discussions and inspections AS NZS 3500 requires that the storage tank be installed as close as possible to the main hot water usage
5. Collectors should be tilted to the latitude angle of the location of installation ideally with a variance of no more than 20 of this angle Table 3 2 Latitude angle for major cities City Latitude angle Adelaide 34 5 Alice Springs 235 4 Brisbane 272 Cairns 22 3 Canberra oJ Darwin p Hobart 42 5 Melbourne 37 42 Perth 3158 Sydney 335 Source Geoscience Australia www ga gov au 52 Chapter 3 Solar Collectors The minimum inclination angle is 1O to allow adequate thermosiphon flow Most standard residential oitched roofs are between 22 5 1 4 pitch and 30 Figure 3 7 compares the latitude angle of Darwin which has the lowest latitude angle and Hobart which has the highest latitude angle Figure 3 7 Graphical representation of latitude angles of Darwin and Hobart a Darwin b Hobart o S T de angle Low 12 2 Horizon Horizon Winter performance can be improved by an inclination angle that is higher than the latitude angle This is possible due to the sun following a lower path in the sky in winter Figure 3 8 The performance gains and losses at inclinations that vary from the latitude angle are shown in Table 3 3 Figure 3 8 Comparative summer and winter sun path Sydney Noon sun angle Collector orientation range 45 E 45 W Summer sun path S SE to SW Table 3 3 Average irradiation gain loss of some Australian cities MJ
6. or iii a heat pump hot water system complying with AS 2712 2002 that has been tested in accordance with AS 4254 1994 and achieves a minimum energy saving of 6096 for a hot water demand level of 38MJ per day for climate zone 3 Water Use in Houses Code PR3 Hot Water Use Efficiency A building must have features that to the degree necessary facilitate the efficient use of hot water appropriate to a the geographic location of the building and b the available hot water supply for the building and c the function and use of the building DTS 3 Hot Water Use Efficiency All internal hot water outlets taps showers washing machine water supplies must be connected to a hot water system or a recirculating hot water system with pipes installed and insulated in accordance with AS NZS 3500 2003 Plumbing and drainage Part 4 Heated water services The pipe from the hot water system or recirculating hot water system to the furthest hot water outlet must not exceed 20 metres in length or 2 litres of internal volume Source 5 Star Codes Brochure www buildingcommission wa gov au bid 5starplus aspx Chapter 13 Requirements for New amp Existing Homes 127 128 Ma m A j g f E N x x Chapter 14 fe f The following list of terms has been provided to assist in the clear use of terms and definitions that are currently used within the plumbing and water industry AS NZS 3500 1 2003 Not all terms
7. 2AJ8A uolsuedx 1942M PJOD by 9A eA HI d V i A 0 Jajem paladua J i enjen Bum eanssejq K Y A Y i SAJCA UJn 9J UO pnumoruon KK d A 8A Bulii dui anjea uollp os de dois Pd M A M A M A y A y i UW WWUQQG gt Y A I I MEE E A l2 LI QC ML E E E L Ox M A I A TEC ME I I Duyse JooY 4 19498 1Q Bm uju LILU00S d BuiurejeH MO 49 eM PjOD JOJ99UUOY pexuel g Y pp i AUB WO x I I I I I sumy UOISSIIAUO m TL AUB oi UJn 94J JOYEM JOH A ultu uJuooS Y UuluuluooSg gt 9 4iLdUH 78 Chapter 6 System Types Ma m A j g f si N x x Chapter A f 7 1 General In many locations the solar fraction is less than required for a solar hot water system to run on its own all year see Table 1 3 Expected solar fraction of capital cities In those cases the solar hot water system will require additional boosting to ensure that water can be heated to 60 C at times of low solar gain i e during cloudy or rainy days AS NZS 3500 requires that the storage tank water be heated to a minimum of 60 C in order to kill and prohibit growth of Leg onella and other bacteria Boosting can be achieved by a an internal electric booster element in the tank b an internal gas burner below the tank c an instantaneous gas unit fed from the solar hot water system d a gas storage system fed from the solar hot water system e
8. Can the pipework be installed at a 1 20 gradient to allow adequate thermosiphon flow d Can the safe tray can be installed correctly to ensure water does not leak into the ceiling e Cana section of roof be removed for installation and replacement of the tank if required f Is there access to the system for installation and ongoing maintenance 14 Chapter 2 Design Principles 2 5 4 Drain back system considerations Figure 2 4 Drain back system Roof mounted solar collectors ITE 4 1 10 grade flow i Y and return lines Tempering valve n Tempered water to internal fixtures N m lim i e Electronic solar pump amp controller KM Cold water inlet 1 SA 4 L General power outlet Before installing a drain back system installers should consider the following a Flow and return pipework should be installed at a 1 10 1 20 slope to allow adequate drain back to the storage tank b The distance between the top of the storage tank and the bottom of the solar collectors can be a minimum of 500mm c The total height of pipework from the storage tank to the collectors is no greater than 7 5m d There is access to the system for installation and ongoing maintenance Chapter 2 Design Principles 15 2 5 5 Heat pump considerations Figure 2 5 Heat pump system Ls Hot water outlet lt A A A A E
9. Darwin 12 5 Hobart 43 Melbourne 58 Perth GI Sydney 34 Source AS NZS 3500 Figure 1 3 The variation in altitude angle according to AS NZS 3500 4 P Altitude angle 30 20 50 Altitude angle 30 Altitude angle 30 20 10 In order to provide 100 of the hot water demand additional boost heating may be required see Chapter 7 Boosting Factors affecting the solar fraction for different regions and installations are a the amount of solar irradiation i e solar access b the temperature of cold water at the inlet c solar system sizing d actual water consumption e ambient air temperature around tank and collector and solar flow and return f pipework and tank insulation g energy needed for boosting and circulating pump Detailed solar radiation data can be obtained from the Australian Solar Radiation Data Handbook published by the Australian and New Zealand Solar Energy Society Chapter 1 Solar Radiation 7 F i A a 2 1 General Solar hot water systems should be designed in accordance with the manufacturer s specifications where those specifications are not in direct conflict with Australian New Zealand Standard AS NZS 3500 4 Environmental and consumer requirements should be factored in when planning the installation of a solar hot water system Factors affecting the performance of a system and decisions about how the system should be installe
10. a solid fuel boiler Notes 1 In the case of b and c the solar hot water system acts as a pre heater to the gas hot water system 2 Heat pumps do not require additional boosting as this is done within the storage tank with an electric element The amount of boosting necessary is dependent on a the quantity of hot water required b the required temperature of the hot water c the amount of solar irradiation d the ambient air temperature e the cold water temperature at the inlet f the efficiency of the solar collectors and storage tank g the efficiency of the booster Figure 7 1 Respective contributions from SHW systems amp boosting to reach average water temperature of 65 C Major Australian cities Average Water Temperature for SWH systems 70 i 3 60 far Y T 50 E o 40 ve 30 9 20 2 10 0 I T f Q dos X AS Q SS S OR S Vv SS Y amp KO VS Location HH Cold Water Temp Increase in Temp due to Solar Bi Increase in Temp due to Boost 80 Chapter 7 Boosting Figure 7 2 Respective energy contributions from solar input amp booster input to reach water temperature of 65 C Major Australian cities Average Energy Required to Heat Water to 65 C 50 a 40 2 7 30 E 20 z 2 Be 10 0 sO S Location
11. and state and territory governments to provide plumbers and other installers of solar and heat pump hot water systems with information on solar technologies and their installation Correct installation of solar and heat pump hot water systems will ensure they comply with state and territory plumbing regulations and achieve high performance This will result in good outcomes for householders and the environment This handbook was written by Global Sustainable Energy Solutions who acknowledge the contributions from ACT Planning and Land Authority Canberra Institute of Technology Commonwealth Scientific and Industrial Research Organisation CSIRO Construction and Property Services Industry Skills Council CPSISC Australian Government Department of Climate Change and Energy Efficiency Queensland Office of Clean Energy and Building Codes Queensland Media Valley National Plumbers Association Alliance National Plumbing Regulators Forum Northern Territory Department of Lands and Planning SA Water South Australian SA Department of Transport Energy and Infrastructure Sustainability Victoria Master Plumbers and Mechanical Services Association of Australia and Western Australian Plumbers Licensing Board This handbook builds on the Household Solar Hot Water and Heat Pump Installation and Maintenance Handbook 2009 developed by the Master Plumbers and Mechanical Services Association of Australia on behalf of the Australian Government Department
12. at least 15 years of record M he rA Ecce ul hania GS Source Bureau of Meteorology www bom gov au Table 1 1 shows month by month the average daily sunshine hours of cities around Australia Table 1 1 Average daily sunshine hours of Australian cities by month Annual JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC average Adelaide 10 3 8 6 4 4 4 5 6 p 8 9 7 Alice 1O 9 9 9 8 8 8 9 9 9 10 10 9 Springs Brisbane 8 8 7 8 6 6 6 8 8 8 8 3 8 Cairns 7 6 6 7 6 7 7 6 9 8 9 8 7 Canberra S 8 7 6 5 4 5 6 7 j 8 7 Darwin 6 6 7 9 9 9 10 10 10 9 9 8 9 Hobart 8 7 6 4 5 4 5 6 6 7 5 Melbourne 9 8 6 5 3 3 5 4 5 6 7 7 6 Perth 10 10 9 7 6 4 5 6 7 8 9 10 8 Sydney 8 7 6 6 5 5 5 7 7 7 6 7 6 Source Bureau of Meteorology www bom gov au 4 Chapter 1 Solar Radiation The sunshine that is absorbed by solar collectors minimises the amount of electricity required to heat water While solar collectors do not generate electricity the energy savings resulting from the solar irradiation reduce the amount of electricity used Figure 1 2 depicts the average daily solar exposure represented as the equivalent in megajoules of energy generated in a year per square metre of surface area Figure 1 2 Annual average daily solar exposure MJ m Megajoules per square metre E gonan ul sul Falun Australian Government Kownryama 13 Bureau of Meteorology s 27 f nnan vo 24 Boa Tengan
13. with the storage tank installed near the main point of hot water use kitchen or bathroom and the collectors further away Pipe insulation is critical for minimising heat losses c Add additional collectors to compensate for the effect of shading d Use an alternative form of solar water heating such as a heat pump or some other form of water heating 5 5 5 Mountings Collectors should be mounted directly on to the roof structure or on to mounting frames supplied by the manufacturer in accordance with the manufacturer s specifications The standard mounting frame kit for a solar water heater system includes a two horizontal mounting rails b four vertical straps to attach the rails to the roof c appropriate screws Timber is not a suitable framing product It is important to consider the wind loads in the location where the collectors are being installed In extreme wind or cyclone areas it may be a requirement that collectors have cyclone mounts Manufacturers have information on best practice installation for collectors in non cyclone and cyclone areas and they should be consulted when required AS NZS 1170 1 is the relevant standard for wind loadings on such structures Where a suitable north facing section of roof is unavailable a mounting frame will be required Figure 3 9 Mounting frame configurations for different roofs a Standard Pitch Mount b Side Pitch Mount Collectors Collectors Side pitch frame
14. 1999 Renewable energy options for hot water systems in remote areas World Renewable Energy Congress Murdoch University Perth WA Master Plumbers and Mechanical Services Association of Australia amp Sustainability Victoria n d Large scale solar thermal systems design handbook National Health and Medical Research Council 2004 Australian Drinking Water Guidelines 6 National Water Quality Management Strategy Nunez M 1990 Satellite estimation of regional solar energy statistics for Australian capital cities Meteorological Study No 39 Canberra Australian Government Publishing Service Phillips RO 1992 Sunshine and shade in Australasia Australian Government Publishing Service Canberra Plumbing Industry Commission Australian Standards 2004 Heated water systems SEIA Solar Energy Industry Association 2001 Solar water heating training handbook O gt a taS i c lt d 140 Chapter 16 Resources Information websites for consumers Australian Government Department of Climate Change and Energy Efficiency www climatechange gov au Fact sheets on hot water systems solar electric or gas booster heat pump e gas Information on phase out of electric hot water systems NABERS The National Australian Built Environment Rating System www nabers com au home hot water fact sheets Chapter 16 Resources 141 wo qe e RAS mm a lt ba
15. 3458 3462 3 4494 4615 3 6396 6398 4 3463 3465 3 4620 4724 1 6401 6439 3 3467 3469 4 4725 4725 2 6440 6440 2 5472 5520 3 4726 4726 1 6441 6444 3 3521 3522 4 4727 4731 2 6445 6452 4 3523 3649 3 4732 4733 1 6460 6640 3 3658 3658 4 4735 4736 2 6642 6725 2 S659 3660 4737 4824 6726 6743 1 3661 3661 4 4825 4829 2 6751 6799 2 5662 5799 3 4830 4895 1 6800 6997 3711 3724 4 5000 5214 7000 8873 4 5725 3749 5 5220 5225 4 9000 9729 Source ORER www orer gov au publications pubs register postcode zones v1 1107 pdf Chapter 12 Government Incentives 117 The examples in Table 12 2 show the RECs produced by solar water heater and heat pump systems in the different zones Table 12 2 Allocation of renewable energy certificates in different zones Eligible Eligible Zone 1 Zone 2 Zone 3 Zone 4 Brand Model from to RECs RECs RECs RECs o S c pt Subece System A ABCOOOO 2007 2020 30 26 30 30 15 July 5 Dec A System B ABCOOOO2 2008 2020 2 2 2 17 870 872 2 5902 5996 4 5264 5270 System A one collector 180 L tank electric boost t System B heat pump 250 L capacity Householders have two options for gaining financial benefit from their RECs Option 1 agent assisted Householders can find an agent and assign their RECs to the agent in exchange for a financial benefit which could be in the form of a delayed cash payment or upfront discount on the system A majority of owners take this option Option 2 indivi
16. 9 4 Collector straps mounted to a metal roof Upper tank support straps screwed into rafters Upper retaining bracket screwed into rafters Roof battens Lower collector support straps attached 200mm from the outer edge of the retaining bracket Storage tank Rafters Solar collectors Lower retaining bracket Chapter 9 Installation Considerations 99 lt 2 e Edd Ja e e im Maras Figure 9 5 Collector bracket mounted to rafter metal roof am e po ha e E pes tad Roofing screw Rubber grommets Collector strap N x etin Ban Metal roof A Roof batten 10 amc anc Poca ci Ral Pacco conf Bat aci ca Roma Puce Pane Races ca nce am aay Rca me amc Rss ase fecal ne Fo 0 tn The collectors should be placed on the retaining bracket and joined using the supplied compression fittings and affixed to the retainer with the supplied locking brackets The upper supporting straps should be attached using the same technique used to attach the lower supporting straps Note In close coupled systems upper retaining brackets are affixed to the top of the collectors in place of the support straps to allow the storage tank to be mounted see section 9 2 2 Mounting tanks Flat plate collectors can reach temperatures in excess of 200 C in direct sunlight Collectors should remain in their protective covering until they have been mounted to redu
17. Five way connector fitted to an existing electric storage tank Hot water flow to tempering valve D Dip tube Thermal sensor to solar Cold water inlet pump controller a Repositioned dip tube Hot water return Thermostat from collectors TO s Electric booster element 5 way connector Cold water flow to pump for circulation to collectors Note The dip tube is positioned upward to promote stratification in the storage tank and prevent the heated water from being redrawn from the outlet to the collectors wu RAJ f c us y Chapter 6 System Types 27 Figure 6 17 Retrofit conversion of existing electric storage tank installation diagram ulu ul gt uun19J MO J JeJoS poje nsur ujud aja 9u0g joj58uuoo em an1y y10Medid JejeA pio Josues ejnyejeduie JOH paje nsun ylomedid Jojem 10H Je O41u09 9 dund Tejos 21U0J129 3 peye nsur AECE ued gt WY xXJowedid sayem pasadwiay uju00 00c Cy Y Y ET y A qum m ZEEEEEEE VE ES lt d XE EE lt 9 Ul 1916M p OO OA EA uonoejoJd 15014 p nb J m lin A A A I K n EKA Y A nu SALA J I 1 My i Y 9M JOSUBS us UUWL gt lepnno Jamod eeuec A z I AD dl hel Quoulne jevo Yum J204 enen Bunedua E AN Buiquunjd yajul Jayem poo i eqn di A M nn Jouresjs aui q d A Y n n 1 H A d n ou ueq R Y n n 9 A EA Y ld VE A M nn N SOANIXI BUIS IU
18. Slow combustion heaters can be used to provide boost heating by burning solid fuels instead of gas or using electricity Solid fuel heaters are more likely to be installed in rural areas where access to electricity and gas is limited or non existent and there is a supply of firewood The most common forms of solid fuels are a wood chips b timber c coal d sawdust pellets e peat f straw g briquettes In a remote storage system the heated water rises from the solar collectors to the tank by thermosiphon flow The heated water then flows from the storage tank to the boiler where it is heated further rising back into the tank by thermosiphon flow Figure 7 6 shows how water temperature in remote storage systems is boosted by solid fuels Figure 7 6 Solid fuel boosting for remote storage systems Hot water flow to Hot water return tempering valve In ceiling from collectors storage tank Cold water flow Cold supply to collectors to tank EN A Boosted hot water return to tank Y 25mm copper Heat exchanger Hot water flow line to booster 25mm copper Solid fuel boiler ground level The solid fuel boosted heater is an uncontrolled energy source that may produce unexpected surges in water pressure and temperature This system should be low pressure and open vented with the header tank lower than the open vent 84 Chapter 7 Boosting 7 4 1 Installation considerations When installing a boiler
19. The minimum diameter of insulation can be determined by using the R value in Table 5 2 and the corresponding diameter in Table 5 3 Table 5 3 R values and minimum insulation diameters Insulation R value diameter 0 2 9mm 0 5 15mm 0 6 25mm O 58mm Source Adapted from AS NZS 3500 4 5 4 1 5 Insulation construction Insulation should be made of closed cell polymer with a UV resistant coating Closed cell polymer can be defined as a high density synthetic foam Figure 5 1 Figure 5 1 Cross section of closed cell polymer insulation UV resistant Closed cell coating foam Pipework opening 5 4 2 Pipework requiring insulation It is best practice to ensure that all internal and external hot water pipework is insulated to the required R value At a minimum the following pipework should be insulated a flow and return lines from the tank to the collectors b hot water pipework from the tank to the tempering valve c all pipework between the storage tank and hot water unit if applicable d tempered water pipework to the internal fixtures Chapter 5 Pipework amp Fittings 55 5 4 3 Insulation considerations Continuity in pipework insulation must be maintained although sometimes many lengths may need to be joined to cover the full length of pipework In those instances the join should be taped and UV resistant tape used where the join is made on external pipework Where pipework penetrates the ro
20. actuated valve that automatically discharges fluid at a specified set temperature It is fitted to a water heater to prevent the temperature in the container exceeding a predetermined temperature in the event that energy input controls fail to function Tempering valve Vitreous enamel A mixing valve that is temperature actuated and is used to temper a hot water supply with cold water to provide hot water at a lower temperature e g 50 C at one or more outlet fixtures Vitreous enamel or glass is used to line the inside of steel hot water storage tanks to prevent steel rusting It is probably the best form of protection in districts where the water is extremely corrosive ep 4 ud a cz tw 136 Chapter 14 Glossary _ Chapter 15 EZ 4 PS The following standards all have relevance to this handbook some to a greater extent than others As Standards are updated periodically the current applicable Australasian Standard may have superseded the number shown ABCB Building Code of Australia Australian Standards O O AS 1056 Storage water heaters AS 1056 1 1991 Part 1 General requirements AS 1056 2 1985 Part 2 Specific requirements for water heaters with single shells AS NZS 1170 2 2002 Structural design actions wind actions AS 1557 Water supply Valves for use with unvented water heaters AS 13571 2004 Protection valves AS 1357 2 2005 Control valves AS 1361 1995 Electric heat
21. as a booster the following issues should be considered a The heat source should be located below the storage tank to allow thermosiphon flow b The flow and return lines from the storage tank to the boiler should be copper li rise or fall in a continuous gradient ii have no valves fitted to them iv have no dissimilar metals in them v have no elbows fitted to them vi have a diameter relative to the length specified in Table 7 2 connect separately from those lines to the collectors to prevent interference between the two systems vi viii be insulated to the required R value so as not to be a hazard c The storage tank must be copper or stainless steel Vitreous enamel tanks should not be used as the enamel can dissolve at high temperatures d The system must be open vented to the atmosphere to prevent any pressure build up in the boiler e Pressure temperature relief valves must not be used f Boilers must not be connected directly to mains pressure storage tanks g A tempering valve must be fitted to the hot water line to the house Table 71 Minimum pipe diameter for thermosiphon systems Vertical distance m Horizontal distance m 2 4 6 8 1O 1 20 20 25 2 2 2 20 20 25 52 32 3 20 20 20 25 32 4 18 20 20 25 25 5 18 20 20 20 25 6 18 18 20 20 25 Source Adapted from AS NZS 3500 4 clause 7 31 Chapter 7 Boosting 85 86 F i w A a 8 1 General The Departme
22. au cat asp catid 5 Chapter 2 Design Principles 11 2 5 System selection 2 5 Close coupled thermosiphon system considerations Figure 2 1 Close coupled thermosiphon system B Roof mounted hot water storage tank Roof mounted solar collectors Tempered water to internal fixtures FA Cold water inlet es Before installing a close coupled thermosiphon system installers should consider the following a Is the home owner happy with the look of the system on the roof b Is the roof I strong enough to bear the weight of the system when it is full of water or if not li can it be strengthened c Is there access to the system for installation and ongoing maintenance d Have boosting options been considered and discussed with the home owner e g electric or gas instantaneous or storage e Will safety equipment such as cranes scaffolding or safety fencing be required particularly if the dwelling is double story Note that the minimum gradient for the thermosiphon effect is 1 20 unless special piping arrangements tanks or valves are used to prevent reverse thermosiphon flow 12 Chapter 2 Design Principles 2 5 2 Forced circulation split system considerations Figure 2 2 Forced circulation system Roof mounted solar collectors mim m E Aaa da Y Y Hot water storage tank Y Y Y Y T i y empering valve i Y Y Y Y Y Tempered water t
23. cold water flow and return lines connecting the tank and collectors should be insulated Chapter 5 Pipework amp Fittings 55 5 4 1 1 Climate region The climate region where the solar hot water system is located will determine the minimum R value for insulation AS NZS 5500 4 Section 8 has detailed climate maps of Australia Table 5 1 shows the climate regions for capital cities in Australia Table 5 2 shows the minimum insulation R value for climate zones including Alpine areas in Australia Table 5 1 Climate regions for capital cities City Climate region Adelaide A Brisbane A Canberra e Darwin A Hobart C Melbourne B Perth A Sydney A Source Adapted from AS NZS 3500 4 Regions for Hot Water Supply System Insulation Maps Table 5 2 Minimum insulation R value for Australian climate zones Climate region Internal locations External locations Pipes Valves Pipes Valves A 0 3 02 0 3 O 2 B 0 3 0 2 0 3 02 C Non Alpine areas 0 3 0 2 O 6 0 2 e Alpine areas 0 3 0 2 1 0 0 2 Source Adapted from AS NZS 3500 4 Notes 1 If the pipe length is greater than 1m the R value needs to increase to 1 0 2 An alpine area is defined as an area in New South Wales the Australian Capital Territory or Victoria with an elevation of 1200m above sea level and in Tasmania 900m above sea level 54 Chapter 5 Pipework amp Fittings 5 4 1 2 Minimum insulation diameter
24. exchange water heaters AS 1375 1985 Industrial fuel fired appliances AS 1571 1995 Copper Seamless tubes for air conditioning and refrigeration AS NZS 2712 2002 Solar water heaters Design and construction AS NZS 3000 2000 Electrical installations Australia and New Zealand wiring rules AS 3142 1986 Approval and test specification Electric water heaters superseded AS NZS 3500 National Plumbing and Drainage Code AS NZS 3500 0 2003 Part O Glossary of terms AS NZS 3500 1 2003 Part 1 Water supply AS NZS 3500 4 2003 Part 4 Hot water supply systems AS 3565 2004 Meters for water supply AS 3666 2006 Air handling and water systems of buildings AS 3666 2006 Microbial control design installation and commissioning AS 5666 2006 Microbial control operation and maintenance HB 263 2004 Heated water systems Handbook AS 5601 2004 Gas installations AS 3498 2003 Authorisation requirement for plumbing products water heaters all types AS 4032 5 2004 Water supply Valves for the control of hot water supply temperatures AS 4234 1994 Solar water heaters Domestic and heat pump Calculation of energy consumption SAA MP 52 2005 Manual of authorisation procedures for plumbing and drainage products AS 4552 2005 Gas fired water heaters for hot water supply and or central heating AS NZS 4692 1 2005 Electric water heaters Energy consumption performance and general requirements AS NZS 4692 2 2005 Electric water heate
25. from one place to another In solar water heaters it is the water itself or an anti freeze solution that does this job The fluid in a heat pipe does the same thing Inclination or tilt angle A measure of the angle of inclination of the collector to the horizontal plane Insulation Irradiance Insulation is material that reduces the transfer of heat In the case of insulated pipes the insulation material may be rubber or plastic wrapped around the pipe Felt fibre material was commonly used and is still available but nitrile rubber products are now recommended Insulation comes in long rolls and can be wrapped round the pipe Insulation is important in reducing heat losses from hot water pipes Hot water storage tanks are also insulated to reduce the loss of heat from the tank A measure of the solar power per square metre of surface area at any instant International System of units SI unit is kilowatts per square metre kW mp Irradiation ep 4 Lid p a cz tw A measure of the radiant solar energy per unit of surface area SI Unit is Megajoules per square metre The term insolation was formerly used but is no longer preferred kPa A kilopascal is one thousand pascals a measure of pressure LPG Stands for liquefied petroleum gas Megajoule MJ The megajoule is a measure of energy and is equal to one million joules Megawatt hour MWh The amount of energy ge
26. m at inclinations varied from the latitude City Collector inclination variance Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual Adelaide 15 75 43 0 7 6 9 12 0 14 8 13 9 8 7 29 2 5 66 8 4 0 6 Flo 15 0 10 2 4 4 10 46 70 5 9 2 5 2 5 7 996 13 5 15 7 4 8 Alice Springs 15 12 4 8 5 5 276 20 65 0 276 71 55 714570 5 12 076 13 5 1 576 5 60 25 9 l 4 15 9 131 8 7 5 970 14 33 10 576 4 0 Chapter Solar Collectors 33 City Collector inclination variance Jan Feb Mar Apr Ma Jun Jul Aug Sep Oct Nov Dec Annual Brisbane 15 6 9 3 5 0 6 6 0 11196 14 8 13 5 9 5 3 3 21 6 2 7 8 1 296 15 11 9 81 4 4 0 4 4 9 73 6 3 3 2 21 7 3 11 2 12 8 3 6 Cairns 15 13 3 9 4 3 8 2 096 6 7 15 7 4 3 5 1 4 8 0 13 8 14 9 2 6 15 6 3 31 17 71 12 2 6 7 12 9 8 6 3 9 18 6 796 7 596 2 896 Canberra 15 7 7 44 O 996 7 096 11 996 15 296 13 8 8 596 3 0 2 4 6 9 8 5 0 6 15 13 1 9 4 4 5 08 53 73 63 2 5 2 5 7 7 12 0 14 096 4 8 Darwin 15 11 0 6 0 5 5 5 11 2 14 3 13 0 8 3 2 8 2 0 12 1 9 4 6 15 2 9 4 8 3 7 1 796 74 10 3 9 2 4 5 1 6 71 3 2 2 2 0 8 Hobart 15 7 6 46 0 0 5 6 11 2 14 9 13 2 81 2 5 3 2 6 9 86 0 2 1
27. may be powered using photovoltaic solar electric panels 2 Pipework design Pipework should take the shortest possible distance from one connection to the next to minimise heat loss from long pipe runs 2 7 1 Heat traps A heat trap is a U shaped curving of the pipework at the hot water outlet of the storage tank Heat traps are required in those systems where the pipes from the storage tank move vertically upwards on exiting the tank Figure 2 10 Heat trap Storage tank Hot water return N Heat trap from collectors Tempering valve Tempered water to internal fixtures Cold water flow Cold water inlet to collectors Chapter 2 Design Principles 23 Because heat rises the bend in the pipework minimises heat losses from heat travelling back up the hot water pipework In accordance with AS NZS 3500 44 a heat trap is required in new and replacement installations and must be within one metre from the outlet of the storage tank before the first branch with a drop of 250mm from the outlet This is not required if a heat trap is integrated within the storage tank Where an external heat trap is required installers need to refer to the manufacturer s specifications 2 7 2 Ring main Where fixtures are located on the opposite side of the house to the storage tank a ring main may be installed to supply the fixtures and return the remaining water in the pipe back to the storage tank for reheating as shown in Figur
28. points Some jurisdictions may have additional requirements regarding this For example in Queensland under the Queensland Plumbing and Waste Water Code legislated after 1 January 2010 water heaters for any new Class 1 building and Class 1 building for replacement are to be installed as close as practicable to the common bathroom 9 2 Installation 9 2 1 Mounting collectors Roof mounted solar collectors and storage tanks should be mounted in accordance with local OH amp S regulations see section 8 13 for information on the safety measures that need to be observed when lifting collectors and storage tanks onto roofs In all cases manufacturer s instructions should be followed carefully and only those support straps and retainers supplied with the system should be used Where possible collectors should be mounted with a minimum clearance of 500mm from gutters roof edge on all sides This clearance helps with access to panels for installation and maintenance It also helps protect the panels from wind and stop run off from rain jumping the gutter 96 Chapter 9 Installation Considerations 9 2 1 1 Flat plate collectors i gt e Edd Ja e E im Maras Flat plate collectors can be installed flush with the roof in most standard installations However in systems that do not incorporate a PTR or air bleed valve at their highest point the outlet side should be mounted 10mm above the inlet side to ensure that air bubbles exit t
29. reaches 7O C preventing water being circulated to the collectors Solar collectors have either one or two ports at each end Both ports are interchangeable and can function as either inlet or outlet ports Although both ports have the capacity to take a temperature sensor it is the outlet port that takes the temperature sensor Manufacturer s instructions for installing the temperature sensor should be followed 5 5 7 2 Hot water outlet from storage tank Hot water exits the storage tank via a pressure temperature relief PTR valve which protects against excessive temperature gt 99 C and pressure gt IMPa typical pressure setting is 500 kPa AS NZS 5500 4 If either of these conditions is exceeded the valve opens and dumps a large quantity of hot water through a drain or soakage trench Chapter 3 Solar Collectors 59 According to AS NZS 3500 4 2003 clause 2 4 3 Plastic pipes and fittings no plastic pipes or fittings can be used as drain lines from the PTR valve AS 1432 approved copper pipe should be used AS NZS 3500 4 2003 clause 1 9 2 Sanitary fixtures delivery temperature and clause 1 9 3 Acceptable solutions for control of delivery temperatures should be referenced when selecting temperature control devices and reviewing requirements for them AS NZS 2712 states that solar hot water systems provide over temperature protection without draining water The manufacturer s specifications will indicate the type of over tempe
30. relevant state or territory electrical licence 2 2 5 Compliance certificate Requirements for plumbers to provide a certificate of compliance to the authority with jurisdiction over the installation of water heaters and to the householder will vary across states and territories 2 2 4 WaterMark compliance The WaterMark is a statement of certification of compliance with required specifications and standards The compliance is in accordance with MP 52 2005 Manual of authorization procedures for plumbing and drainage products Currently no uniform system requiring a single certification mark is in place MP 52 2005 shows only one certification mark the WaterMark Level 1 and Level 2 The levels denote the level of risk of the products and the need for certification Level 1 has more stringent requirements than Level 2 Level 1 requires compliance with ISO IEC Guide 67 2004 System 5 and Level 2 compliance with ISO IEC Guide 67 2004 System 1b To date the Plumbing Code of Australia 2004 PCA includes the requirements which are necessary for conformance to WaterMark Level 1 and Level 2 State and territory governments will progressively replace MP 52 2005 with the PCA Plumbers and plumbing suppliers will have to check whether solar and heat pump hot water system equipment must have WaterMark certification under PCA legislation in their respective state or territory Further information can be found at www watermark standards org
31. terminate a atleast Im from the storage tank b 200 300mm above ground level c above a drain 5 5 2 5 Tempered water line Tempered water lines must run at least Im from the tempering valve to fixtures 5 4 Insulation Insulation is required to prevent heat loss through pipework Insulation will minimise water wastage and energy consumption when hot water flows to fixtures All hot and cold water pipes and valves running between a storage tank and the solar collector or heat pump should be insulated when installing a solar water heater or heat pump system 5 4 1 Minimum insulation requirements Heat loss from pipes can have a significant effect on system performance Insulation is also important for safety as the temperature of water exiting a solar water heater can be far greater than that in a standard hot water system some components of a solar collector system can reach as much as 170 C Temperatures in different parts of the system will determine the thickness of insulation required However all insulation should be between l3mm and 25mm with thicker insulation used wherever possible Where the insulation is outdoors or exposed to the elements it should be UV ultraviolet rated and weather resistant to ensure longevity and effectiveness See AS NZS 3500 4 sections 8 2 and 8 3 for more details on the insulation requirements for hot water installations for example the requirement that all pipework including hot and
32. the object will cast a shadow on the collector Table 3 4 Sun s midwinter June angle above the horizon for capital cities Latitude City angle Angle of sun 9am Noon 5pm Adelaide 54 5 24 1 SES 24 1 Brisbane 21 2 21 4 59 5 21 4 Canberra 35 17 18 2 51 7 18 2 Darwin 12 2 46 6 49 8 46 6 Hobart 42 5 13 6 24 3 13 6 Melbourne 57 4 18 8 29 18 8 Perth S5 54 4 20 54 4 Sydney 33 5 18 5 55 5 18 3 Source NASA www nasa gov Alternatively Australian Standard AS NZS 3500 4 Appendix I provides a simple cardboard tool for assessing shading Refer to the standard for more details 3 3 4 3 Actions to address shading If all the collectors are shaded in the middle of the day they should be moved if a less shaded position can be found Shade will significantly reduce the hot water output potential of the collectors Where the collectors are subjected to shading between 9am and 5pm eastern standard time the following actions may be taken a Remove the source of shading e g where shading is caused by a tree or other plant life pruning or removal of the plant may be possible b Relocate the collectors i Collectors may be installed higher on the roof or on another part of the roof that will not be shaded ii It is possible that if the collectors are a long way from the point of use a close coupled Chapter 3 Solar Collectors 55 system should be replaced by a pump circulated system
33. the water in the storage tank Figure 6 6 shows the configuration of a standard heat pump compressor Figure 6 6 Heat pump compressor Expelled cold air Exhaust fan Condenser a Evaporator Air intake vent Warm air flow N N Cooled refrigerant ________ Hot refrigerant vapour liquid return to Air heated refrigerant flow to tank evaporator vapour flow to condenser Note The configuration of the heat pump compressor may vary between manufacturers 6 5 5 Heat pump storage tank The heat pump storage tank operates on the heat exchange principle Vapour from the compressor flows through a coil or mantle arrangement of copper pipework submersed inside the cylinder or wrapped around it The heat is transferred to the water in the storage tank by contact with the copper pipe Figure 6 7 shows a typical heat pump storage tank 66 Chapter 6 System Types Figure 6 7 Heat pump tank Anode cap Heated refrigerant Cooled refrigerant condensar return to dial Se Anode Vitreous enamel tanks Hot water outlet to tempering valve BA gt ql PTR valve Outer casing Stratification of water High density tank insulation Heat exchanger coil Cylinder PTR drain line Cold water Inlet 6 5 4 Heat pump operation A heat pump is made up of an evaporator condenser compressor and the storage tank The refrigerant in the evaporator absorbs heat from the
34. tiles at each strap will need to be removed to expose the rafters The support strap should be bent to run flush with the rafters The front roof tracks should then be attached to the support straps with the top manifold attachments affixed to their respective locations On metal roofs roofing screws may be used to screw the front tracks through the roof and into the rafters roof structure Rubber grommets or pads should be used with the roofing screws to lift the metal frame off the roofing material to prevent corrosion The horizontal support braces are attached with even spacing down the front tracks Tube clips or caps are attached to the bottom track to hold the evacuated tubes in place The manifold can be positioned into the attachments on the top track and individual tubes inserted into the manifold Evacuated tubes can reach temperatures in excess of 200 C in direct sunlight It is important therefore that the evacuated tubes are inserted as the final step to prevent unnecessary heating and the risk of injury to the installer Chapter 9 Installation Considerations 101 oy e Gaa f x x E Vea 9 2 1 3 Cyclone and high wind mounts flat plate collectors In cyclone and high wind areas installers should use collectors approved by the local authorities Collectors should be fixed to roofs with a fixing method that is suitable for the application under the local building codes and OHSS regulations For example
35. to rafter cross section tiled roof Roofing screw Collector strap N Rubber grommet Roof batten N N ze mm Q PR RA ER S ct et S P et RH Pa a i H 98 Chapter 9 Installation Considerations On metal roofs roofing screws may be used to screw the support bracket through the roof and into the rafters roof structure Rubber grommets should be used with the roofing screws to lift the metal frame off the roofing material to prevent corrosion The installer must ensure that for metal roofs the solar hot and cold pipes between the water storage tank and the solar collectors are a copper b fully insulated according to AS NZS 3500 4 clause 8 24 c Plumbing and Drainage Heated Water Services of a suitable material and thickness minimum thickness 15mm c weatherproof d UV resistant if exposed The insulation provides protection for the metal roof against any water run off over the copper pipe It will also reduce heat losses in the pipe and protect against accidental contact with the hot solar pipe work Manufacturers instructions relating to the specific model of thermosiphon solar water heater to be installed must be followed to ensure that the appropriate insulation has been fitted to the connections on both the solar collectors and the storage tank Figure 9 4 shows how collector straps are mounted to a metal roof Figure 9 5 shows a collector bracket mounted to a rafter on a metal roof Figure
36. unfamiliar with a task and who present a risk or hazard that needs special attention and risk control measures i The interior of the roof is a confined space licence required Is the enclosed working area safe and have all hazards been identified IMPORTANT NOTE This list is not exclusive The total list of risk factors to be assessed will differ for every installation and will depend on the site the residence the type of system being installed and the installer s methods 8 5 Risk of falls The first priority when working at heights is always to prevent falls Safe working procedures and suitable barriers will help prevent falls Commonwealth state and territory OH amp S regulations in Australian do not specify a particular height at which it becomes necessary to introduce safe procedures for working at heights But in New South Wales the Safe Work on Roofs publications specify that if a physical restraint or harness is used it needs to be able to stop a fall from 2m or more 8 6 Three types of control measure safe operating procedures Three types of control measures and safe operating procedures can be used to minimise the risk of falls ils The provision and maintenance of a stable and securely fenced work platform Cincluding scaffolding or any other form of portable work platform 2 The provision and maintenance of secure perimeter screens fencing handrails or other physical barriers to prevent falls 5 Perso
37. 0 all new houses and renovations must be 6 star out of 10 From March 2010 all new units have been required to be 5 star This policy overrules any existing covenants or body corporate rulings for solar water heaters www climatechange qld gov au __data assets pdf_ file 0003 25626 3_P and B_ _El_web pdf This imposes additional requirements that require all new houses to have greenhouse efficient water heaters Queensland has in place requirements under which building body corporates must approve energy efficiency building measures and supply a mandatory sustainability declaration From January 1 2011 Queensland plumbers must have a solar and heat pump endorsement on their trade licence to be able to install low greenhouse gas hot water systems www sustainable homes org au SA SA2 amp SA7 Variation to BCA Vol 2 Regulation 80B From 1 July 2008 new and replacement water heaters installed into most homes in South Australia have needed to be low emission types such as high efficiency gas solar or electric heat pump A solar or heat pump water heater must achieves i in a home with three or more bedrooms at least 22 renewable energy certificates in Zone 3 ii in a home with one or two bedrooms at least 14 renewable energy certificates in Zone 3 A gas water heater must have an energy rating label of 2 5 stars or greater Website www planning sa gov au go hot water services TAS None Identified Check with l
38. 0 Soft but possibly corrosive 60 200 Good quality 200 500 Increasing scaling problems gt 500 Severe scaling Source Australian Drinking Water Guidelines 2004 Fact sheets Hardness as calcium carbonate Note Soft water may lead to corrosion of pipes but is dependent on the alkalinity pH of the water Water hardness above 200mg L is associated with excessive scaling of pipes and fittings and may also cause blockage in pressure temperature relief PTR valves Chapter 4 Storage Tanks 45 lt ec eis m 2 e T taf 4 3 Types of tanks Storage tanks are typically made of the following materials a stainless steel b copper c vitreous enamel lined steel d plastic or rubber for atmospheric pressure formats Stainless steel and copper storage tanks tend to have a longer life where the water quality is good but as with all storage tanks they suffer from corrosion if the water quality is poor Vitreous enamel storage tanks can withstand poor quality water due to the enamel coating inside the tank However corrosion is a potential problem Figure 4 1 shows a typical horizontal storage tank with water stratification Figure 4 1 Typical horizontal storage tank Heat Exchanger outer casing Insulation Hot Water zt nim d TERR Phomme a a al j CX c r E PIE E NNI CNN E ICONES 7 a I T 4 gt k E i Uj REE me E ca a L aaa n id N l Cold Wate
39. 2 and installed to the manufacturer s instructions where that standard and instructions are not in conflict with AS NZS 3500 4 3 2 Types of collectors Solar collectors are either flat plate collectors or evacuated tubes 3 2 1 Flat plate collectors Flat plate collectors consist of a darkened absorber plate in a glass fronted box Solar radiation is collected by the absorber plate converted to heat energy and transferred to the liquid water or glycol in the riser tubes attached to the absorber plate The number of riser tubes and their size may vary between collectors As the liquid warms it rises to the top of the collectors by thermosiphon flow A layer of insulation helps keep the temperature inside the box higher than the ambient temperature Collectors can be joined together to form an array when the hot water demand is higher Figure 3 1 Typical flat plate collector Header connections to valves collector or hot water return Riser tubes Header connection to collector valve or cold water flow Transparent hardened glass cover Header tube Absorber plate Collector box Insulation Termination plug or connection to collector valve or cold water flow 28 Chapter 3 Solar Collectors 5 2 2 Heat pipe evacuated tube collectors Evacuated tube collectors shown in Figure 3 2 are formed from an array of hardened glass evacuated tubes joined to a manifold through which the heat transfer liquid water
40. 4 BAILA J I 1 My Ijam JOSU8S an en Bunedua JeurieJs our SALA H ld A 8A uolsuedx J9 eM D OO onen Huu eansseJg A 8A UJn 9J UON SAA UOI EJOS X IN lt a F OOOO nd 91019409 ERN ule ES lt UIW Uu gt yug eDeJojs Bunsixa Jo Aju Jajem pJOO O Sj2euuoo MOJ J91eM 10H UY u1u00 00c i gt gt SOINIXI euJ9 ul O Jojem poJeduJe Bulyse yy jooH A A A A Y A A n Y A n Y A n A uww gt t jepno amod Kh i Je3euoc i i n A i A a a a a a A v A ou ureJq lt ou ureJq A 8A H Ld 19 eM pajesy A 8A H Ld Je OS 9AI9291 0 9 qejins Jayesy Jayem Joy Bulsix3 I oxoeJq uiu LULUQOS Jeddoo wws yu UJOJJ MOJ JOYEM poo uoissaJdujo ellEEEEPETT A m i ib i E ee el RA GT PLELLLLLLLLLLEEEEEEEEE h mm PO ib bi dl A A A AAA AAA AAA ooo ooo ww a a DuiuiejoH suy an EEEEEEA ELL q qd I IA q q q q q q I q 9 4iLdUH peunouJ amp M JO yUe 19 011u09 dund JeJOS 2129 3 jejut 192M pog s Y E e Y ml A A AAA Aaa Aa ad im xdi fiuouine e20 uim y99uO Duiquunjd Jour Jajem PjOD Josues eJnjeJeduJuo P P P P el e e e ee a Ku AZ yue Heos 191eou aJd Jejos L P P P P P P el el P P P
41. 4 1 pH level classification pH Classification lt O Strong acid T 5 Weak acid e lt 7 Neutral had 9 Weak alkaline 14 Strong alkaline Source Adapted from the Australian Drinking Water Guidelines 2004 Factsheet pH pH levels outside the range of 6 5 and 8 5 can be associated with corrosion and pipe blockage due to calcium build up 44 Chapter 4 Storage Tanks 4 2 2 TDS TDS or total dissolved solids are particles of sodium potassium calcium magnesium chloride sulfate bicarbonate carbonate silica fluoride iron manganese nitrate and nitrite phosphate and other organic matter that is dissolved in the potable water supply TDS values above 500mg L can be associated with scaling inside tanks pipework and household appliances Corrosion may also be a problem with higher TDS levels Table 4 2 rates the water quality at different TDS values Table 4 2 TDS water quality classification mg L Quality 80 Excellent 80 500 Good 500 800 Fair 800 1 000 Poor 21000 Unacceptable Source Australian Drinking Water Guidelines 2004 Fact sheets Total dissolved solids 4 2 5 Hardness Water hardness is measured by the concentration of calcium and magnesium calcium carbonate equivalent in water Table 4 5 rates the water quality at different classifications lt e e e EL dis bel Table 4 3 Water hardness classification mg L Classification lt 6
42. 5 12 8 9 5 4 9 0 0 4 396 72 6 2 2 3 31 8 2 12 0 13 4 5 3 Melbourne 15 7 5 4 4 O 696 6 5 111 13 7 12 4 7 6 2 2 2 696 6 6 8 296 0 0 15 12 8 9 5 4 6 0 5 4 7 6 7 5 7 19 31 7 7 11 6 13 3 4 9 Perth 15 8 3 4 2 1 6 7 5 121 14 9 13 5 8 9 3 6 2 096 71 9 3 0 2 15 14 0 9 7 4 0 17 5 4 75 6 5 3 0 1 9 7 4 12 8 151 5 1 Sydney 15 6 9 41 0 4 6 0 11 6 15 5 13 9 91 31 2 396 64 7 9 1 0 15 12 1 9 0 4 6 0 7 4 996 75 6 7 2 8 2 3 7 3 11 4 131 3 9 Source Adapted from Bureau of Meteorology irradiation maps using variation formulas from NASA irradiation tables 34 Chapter 3 Solar Collectors 5 5 4 Shading Collectors should be located in the sunniest area avoiding shade between 9am and 3pm each day This is of particular importance in winter when solar irradiation is less than in summer and demand for hot water may be higher 3 3 4 1 Shading exceptions As per AS NZS 3500 4 partial shading from small objects such as flues chimneys or TV antennas is permissible 5 5 4 2 Estimating shading To ascertain whether or not the collectors will be subjected to shading it is important to know where the sun s position will be at its lowest point in the year in midwinter An inclinometer can be used to measure the altitude angle of any potential obstructions and compared with the data in Table 3 4 to ascertain if
43. East facing Standard pitch root north facing Standard collector straps Under tiles or on metal roof c Reverse Pitch Mount Collectors d Flat Pitch Mount Collectors Reverse 9 OMS R pitch frame Flat pitch north facing Standard inclined frame South facing roof inadequate north facing area 5 5 6 Frost protection As the outside temperature drops water can freeze When water freezes it expands causing a pressure build up that is capable of bursting copper pipes In frost prone areas frost protection techniques will prevent system failure resulting from frozen or burst pipes It is important to identify the likelihood of frost in a particular area to ascertain whether or not it will pose a threat to the system Figure 5 10 shows the number of potential frost days in Australia 56 Chapter 35 Solar Collectors Figure 3 10 Annual potential frost days Potential frost days Annual Minimum temperature less than 2 C Based on a standard 36 year climatolegy 1978 2005 E oCummrnameah of Arda SOO Projecton Lambert conformal with Source Bureau of Meteorology www bom gov au Table 3 5 Annual potential frost days for some Australian cities City Number of days Adelaide O 10 Alice Springs 50 40 Brisbane O 1O Cairns O 1O Canberra 1002150 Darwin O 1O Hobart 150 Melbourne O 1O Perth O 1O Sydney 0 10 Source Bureau of Meteorology www bom gov au Cha
44. OJ epeJb OL L _ Bulyseyy jooH Bc yue UJOJJ Pa MOI Joyem POD joxoeJq uju uiuoos P d Bulurejay Y sbumy uoisseJdujo BN 4 utu WWQOS y uw uuoog gt uun19J MO JeJOS poa1ej nsur womedid Jojem PjOD paje nsul yJOmedid 19JEM JOH peyejnsur xX1oMedid Jajem paladua SALA J91 91 Jl V Jem JOSUBS onen Buuedujie J9Ule 1 s our SALA H ld A 8A uoisuedxa J9 eM pro onen Buniuui e1nssald A 8A UJn 9J UON OA EA UOI eJOS 40jo9euuoo pexuelg Buluse jooy Yue 0 UJn 9J 19 eM JOH KAANAUxXEOoel Chapter 6 System Types 65 wu CE RES j k ami 6 5 Heat pump systems 6 5 1 General A heat pump system is a form of solar water heating that uses the standard refrigeration cycle to transfer heat from the ambient outside air temperature into the water in the storage tank or solar radiation to directly heat a refrigerant fluid in a collector 6 5 2 Heat pump compressor The heat pump compressor is considered a solar collector even though it does not rely on direct sunlight to heat water A heat pump relies on the ambient air temperature for its solar gain Heat pump compressors operate on the refrigeration principle in that they extract the heat from the ambient air to heat a pressurised refrigerant that is circulated from the evaporator through the condenser The heat is then transferred to
45. Pipework In this book the word pipe can mean pipe or tube Strictly speaking pipe is measured internally and tube is measured externally To be technically correct we should not speak about copper pipe but rather copper tube because it is the outside diameter which determines its size Steel pipe and most plastic pipes are measured according to the internal hole size and so are pipes not tubes ep qa f LJ e cz tw Potable water Water classified under Australian Standards as suitable for drinking Pump circulated or pumped storage systems This type of system consists typically of a ground mounted tank and roof collector panels A small circulation pump is used to pump water through the collectors A differential temperature controller with two or more temperature sensors is used to control the pump operation Pump circulation frost protection By pumping water from the storage tank through the collectors the water in the collectors can be prevented from freezing if the water in the storage tank is warm Radiation The transfer of heat by its conversion to electromagnetic waves or photons tiny packets of energy Chapter 14 Glossary 1535 Renewable Energy Certificates RECs Certificates issued under the Federal Government s Mandatory Renewable Energy Target MRET scheme that represent IMWh of renewable energy electricity generation or IMWh of electricity saved through the use of sol
46. SOLAR amp EXT EL SYSTEMS Plumber THE PHASE OUT OF GREENHOUSE INTENSIVE HOT WATER SYSTEMS a joint initiative of the Australian State and Territory Governments Published by the Department of Climate Change and Energy Efficiency May 2010 www climatechange gov au ISBN 978 1 921298 97 4 Commonwealth of Australia 2010 This work is copyright Apart from any use as permitted under the Copyright Act 1968 no part may be reproduced by any process without prior written permission from the Commonwealth Requests and inquiries concerning reproduction and rights should be addressed to the Commonwealth Copyright Administration Attorney General s Department National Circuit Barton ACT 2600 or posted at www ag gov au cca DISCLAIMER This publication has been compiled as a guideline for the installation and maintenance of solar and heat pump hot water systems The information contained in this publication does not override occupational health and safety legislation Commonwealth state or territory standards and manufacturers installation requirements which should be adhered to at all times You should not act or fail to act on the basis of information contained in this publication Due to the wide variety of products on the market the technical diagrams illustrate the general principles of the technologies and may differ in appearance from actual products This publication is not a substitute for independent professional advi
47. Solar Input M Booster Input 7 2 Electric boosting 7 2 1 Electric storage In electric boosted storage systems one or two electric elements are immersed inside the storage tank An electric element is curved in shape and can be positioned so the curve points up or down to provide varying amounts of boosted hot water A thermostat controls the boosting element by switching it on when the water temperature drops to a pre determined temperature and switching it off when the temperature reaches 60 C Figure 7 3 shows the configuration of an electric boosted storage tank Figure 7 5 Electric boosted storage tank Anode cap High density tank insulation Hot water return from solar collectors d Dip tube standard solar Dip tube standard solar Hot water outlet to tempering valve b N Outer casing Anode Cylinder Thermostat Electric element where boosted Lue M n E FA T Stratification of water Cold water flow to solar collectors a Thermostat Cold water Inlet E Dip tube retrofit Chapter 7 Boosting 81 7 2 1 1 Off peak tariffs Where available an electric element can be supplied by the electricity supply company during off peak hours These hours may vary between states but can be between 9pm and 7am the booster is only active in the evening night hours The system size requirements to qualify for off peak electric rates vary between states and should be checked w
48. UU o Y suoneoioeds SAMBA SJoJnjoejnueuij o s 52ueuie O ul ureJq Buu duu l Jono 19 8M JOH SALA H Ld 9 4iLdUH 70 Chapter 6 System Types 6 6 Retrofit systems A retrofit system is one where a solar hot water system is installed or integrated into an existing hot water system A fundamental point is that a solar hot water system must have hot water storage as it is not possible for solar collectors to provide continuous hot water at the required temperature all year round Retrofit systems are commonly installed using close coupled or split systems however a gravity feed system can also be used 6 6 1 Existing gas storage system In this type of installation the solar hot water system acts as a pre heater to the existing gas storage system This means that there are two storage tanks l the solar storage tank which holds the pre heated water from the collectors i the existing gas storage tank which boosts the water from the solar storage tank and supplies the internal fixtures Figure 6 11 shows a close coupled retrofit system and Figure 6 12 shows a split system retrofit D ce d fp pes lt w Chapter 6 System Types 71 Figure 6 11 Pre heater close coupled system retrofit to existing storage tank installation diagram u1n194 M0 J 16eJOS po1e nsui ylomedid 191eM ploy paje nsu1 10Medid 19Jem 10H paje nsul yiomedid Jayjem peJeduJoe onen UONDAJOIA 1SO14 an en Du
49. ansion and contraction of materials under high temperature conditions e pr ha a XL im Ld J All materials fittings connection points and components are suitable for use under the expected temperature and pressure conditions Regulatory All collector attachment points meet regulatory requirements C Installation meets the requirements of AS NZS 3500 4 and other applicable standards covering the work completed a All components have been installed to meet regulatory requirements and have been approved for use in Australia Boosting The auxiliary boosting option is functional and is connected to the correct fuel or energy tariff Cif applicable C A timer has been installed on the auxiliary boost and is operational Cif applicable C Heat pump is connected to continuous electricity tariff where applicable Pump controller C The temperature sensors have been installed to the correct outlets and the leads connected to the controller C The electricity supply has been connected and the unit switched on to ensure it operates General Proper clearances have been observed and there are provisions for future maintenance AIl components have been installed to manufacturers specifications The system has been tested is operational and has been checked for leaks Descriptive labels have been applied to pipe work and components The site is neat and tidy A full risk assessment of the site has been condu
50. ar collectors tilt angle of solar collectors particles in the atmosphere 1 2 Solar fraction The solar fraction can be used as an indicative measurement of the relative energy performance benefit of solar hot water heaters greenhouse gas emission reduction and energy cost savings The solar fraction is calculated as the proportion of the hot water energy demand provided by the solar collectors in relation to the boosting energy required to keep water at the required temperature Table 1 3 shows the average expected solar fraction for Australia s capital cities The figures are based on a household with three to four occupants and a water usage of 150 litres to 200 litres per day Table 1 3 Expected solar fraction of capital cities City Solar fraction Adelaide 74 Brisbane 81 Canberra 67 Darwin 97 Hobart 65 Melbourne 67 Perth TE Sydney 7696 Solar water heaters should always face the sun In Australia a north facing roof is ideal The tilt angle of the collectors for best all round performance will depend on the latitude in which the systems are being installed Solar collectors are best located facing due north and elevated from the horizontal to a tilt angle equal to the location s latitude 6 Chapter 1 Solar Radiation Table 1 4 Ideal angle of elevation for solar water heater collectors in capital cities City Latitude angle Adelaide 55 Brisbane 27 3 Canberra 555
51. ar water heaters Renewable Energy Target RET Australian Government target to increase renewable energy generation Retrofit Taking an existing system and changing it usually upgrading it In the case of a hot water system it can be retrofitted by the addition of solar collectors and equipment to convert it into a solar hot water system Reverse thermosiphon Reverse of thermosiphoning i e circulation in the direction that is not required In the case of a solar water heater reverse thermosiphon is the circulation of heated water from the storage tank to collectors resulting in cooling This happens at night if the collectors are not mounted below the storage tank Ring main A pipe that runs round all the hot water delivery points and has hot water circulating though it so that whenever a tap is turned on hot water is instantly available R value Is a measure of thermal resistance Sacrificial anode A sacrificial anode is dissolved rather than some other item Anodes are installed in mild steel vitreous enamel lined tanks to prevent corrosion of the tank The anode consists of a long aluminium or magnesium rod running along the inside length of the tank Safe tray ep LL p a cz wr Another name is a spill tray or an overflow tray It is a water collecting tray designed to catch water that leaks out of a hot water storage tank or a cold water tank such as a header tank A safe tra
52. ar with constant motion within gravity feed header tanks As this wearing is irregular it may be sufficient to replace the washer when leakage occurs If replacing the washer does not stop the leaking the valve may need to be replaced 10 2 5 Expansion valve on the cold water supply The expansion valve should be replaced if it constantly leaks Where this failure occurs at set time intervals then a replacement schedule should be considered so that the valve is replaced before its fails The expansion valve on the cold water supply as with the PTR valve is designed to release water as it expands Minor leakage is of little concern 10 2 4 Non return valve Non return valves rarely need replacing However if a non return valve is failing the cold water supply pipe may feel warm some distance from the storage tank The valve will need replacing if this is the case 10 2 5 Isolation valve The isolation valve should completely stop the flow of water to the hot water system If the valve is allowing water through the washer or the valve may need replacing 110 Chapter 10 Maintenance 10 5 Corrosion and scale formation 10 5 1 Valves Areas with highly corrosive water may cause valves to fail frequently Replacing the valves as part of a maintenance program may be required e kay j a lt Wap 10 3 2 Sacrificial anodes The life of a sacrificial anode will depend on the quality of water supplied to the system In ar
53. ate mechanical lifting equipment for collectors tanks and other equipment is another occupational health and safety obligation As most solar systems collectors only or collectors and tank are roof mounted installers need to devise a plan to move all equipment onto the roof prior to beginning work 92 Chapter 8 Occupational Health amp Safety Some common solutions a hiring a small crane to lift roof components quickly and safely b engaging suppliers who will deliver all components to the site and onto the rooftop Rope and pulley solutions are slow and can easily result in injury to installers so they are not recommended Whenever mechanical lifting equipment is used installers must assess all risks associated with the equipment and introduce appropriate control measures to contain the risks The following list is not comprehensive however examples include a the risk of manual handling injuries to workers while using equipment can be controlled by guarding the drive mechanisms and nip points on the elevator belt b barricading the area around the equipment to prevent access by untrained people and limiting the risk of falling objects hitting people below c training people to use equipment in some circumstances people will be required to hold certificates of competency for example for operating a builders hoist 8 13 Roof security There will be risks involved in mounting heavy equipment onto a residential
54. ater boosting options v detailed diagrams of common solar and heat pump hot water system installations b ensure new homes built in Australia meet new building codes and sustainability standards c promote a high standard of installation for solar and heat pump hot water systems By achieving those objectives this reference guide will help ensure a Consumers have access to continuous hot water as a result of optimum design installation and ongoing maintenance procedures b People are safeguarded from injury or loss of amenity because the risk of the hot water supply failing as a result of poor installation maintenance or operation has been reduced c The quality of the environment is maintained because environmental impacts have been minimised The scope of this reference guide is limited to household solar and heat pump hot water systems and does not include commercial hydronic or pool heating or geothermal technologies 2 Introduction Chapter 1 A a 1 1 General Irradiation is the energy emitted from the sun that is subsequently absorbed by a solar collector The amount of irradiation depends on the latitude of the solar collector Figure 1 1 depicts the average daily sunshine hours Australia is exposed to over 12 months Figure 1 1 Average daily sunshine hours annual w n I DARIAN a m i rh Number of x n pp Average daily sunshine hours i Annual i standard parallels 10 4095
55. ations will indicate the decibel rating of the heat pump and advise on specific clearances Heat pumps are continuous electric water heaters and therefore must be connected to the continuous power outlet They require a standard 10A connection Depending on the manufacturer s requirements the connection can be hardwired or connected through a GPO general purpose outlet A licensed electrician must make all electrical connections Follow the manufacturer s recommendations about appropriate water pressure for cold water inlets Where water pressure is too high a pressure limiting valve may be necessary Installation in ceiling cavities or roof spaces is not recommended for heat pump systems because heat pumps need ventilation If there is not enough ventilation the roof space will quickly cool and the heat pump will not operate In summer roof spaces can be very hot and the heat pump system may overheat Figure 9 10 Integrated heat pump unit showing sample installation amp relative distances required around heat pump unit 4 Height 2 3 m height of heat pump base and extended feet Fan Grill Outflow PTR Valve ESI Connection v B ccc Hot water outlet Cold water inlet 1 83 m p 2 5 m Fee P EE K RR O 1 43 m more than 0 4m min Chapter 9 Installation Considerations 105 oy a kai fece c E ta e ce Gag j x E k 9 2 5 Pumps and pump cont
56. ce and readers should obtain any appropriate professional advice relevant to their particular circumstances While reasonable efforts have been made to ensure that the contents of this publication are factually correct the Commonwealth provides no warranties and makes no representations that the information contained in this publication is correct complete or reliable The Commonwealth expressly disclaims liability for any loss however caused whether due to negligence or otherwise arising from the use of or reliance on the information contained in this publication by any person The views and opinions expressed in this publication do not necessarily reflect those of the Australian Government or the Minister for Environment Protection Heritage and the Arts or the Minister for Climate Change Energy Efficiency and Water Contents Introduction 1 Solar Radiation 11 1 2 General Solar fraction 2 Design principles 2 1 2 2 2 3 2 4 2 3 2 6 2 7 General Legislation 2 21 Building permits 2 2 2 Licensing 2 2 2 Water connections 2 2 2 2 Gas connections 2 2 2 3 Electrical connections 2 2 3 Compliance certificate 2 2 4 WaterMark compliance System selection 2 31 Close coupled thermosiphon system considerations 2 3 2 Forced circulation split system considerations 2 3 3 Gravity feed remote storage system considerations 2 5 4 Drain back system considerations 2 3 5 Heat pump considerations 2 5 6 Retrofit consideratio
57. ce the risk of injury to the installer 100 Chapter 9 Installation Considerations 9 2 1 2 Evacuated tube collectors Evacuated tube collectors use slightly different mounting frames to flat plate collectors They can be attached to the roof in a similar way using straps or direct bolting however tube clips are used to safely hold the evacuated tubes in place oy a kai fece c E aoe ta For roofs where the evacuated tube collectors are to be installed flush to the roof plane the system will have been supplied with the top and bottom support rails plus the device for securing the evacuated tubes to the top rail For flat roofs or roofs with insufficient pitch the evacuated tube collectors will be mounted on a pitched frame The equipment for a pitched frame will usually include the same top and bottom rails but will include a mounting frame to elevate the evacuated tube collectors Evacuated tube collectors should be situated at a minimum of 500mm from the roof gutter and roof ridge at the optimal position on the roof see Chapter 3 Solar collectors Note The side where the hot water return line and air bleed valve are to be attached should be mounted approximately 20mm to 50mm higher than the other side This allows air bubbles that form in the collector to escape to the highest point On tiled roofs the support straps will need to be screwed firmly onto the rafters roof structure not to the tile battens A section of
58. cted All paper work has been completed UU C OD O C Client has been provided with all necessary documentation and operating instructions 108 Chapter 9 Installation Considerations Chapter 10 A a e e pum jo e lt a taf 10 1 General Preventative maintenance should be carried out to prevent failure of any system The frequency of preventative maintenance should accord with the manufacturer s specifications for the installed system This will ensure optimal operation of the system and maintain the manufacturer s warranty The most common causes of system failure are a wear or failure of components b corrosion of components c sediment within the system 10 2 Valves 10 2 1 Pressure temperature relief valve The pressure temperature relief PTR valve should be checked every six months to ensure proper operation As lifting the valve can cause it to bind to sodium deposits on the moving shaft it is recommended that the valve be replaced every five years If the valve is not lifted it may fail and excess pressure could damage the storage tank As the PTR valve is designed to release water as it expands it is not uncommon for approximately one litre of leakage to occur However the valve should be checked if it leaks continuously AS NZS 3500 4 2003 requires the tempering valve to be installed in a position which is readily accessible 10 2 2 Float valve Float valves can we
59. ctors and returned to the storage tank via the hot water return line at the top of the collectors Where evacuated tube collectors are installed the water flows through one side of the manifold along the top of the tubes and is returned through the opposite side in a left to right manner or vice versa The hot water from the upper section of the tank is then supplied to the tempering valve where it is mixed with cold water from the main cold water inlet and then distributed to the household fixtures Figure 6 2 Forced circulation system flat plate collectors split system installation diagram Collectors xj Stop tap Isolation valve 2 Non return valve gt Pressure limiting valve I shig Cold water expansion valve KX PTR valve Line strainer Tempering valve a a m Sensor well PTR Valve we Air relief valve N Tempered Water m PTR Drain Frost protection valve i if sl aaa N y Dip Tube Tempered water pipework Cold Waieriniet OOO n insulated GPO i tad gt gt gt gt s n Hot water pipework insulated ra Y En Cold water pipework Electronic SS insulated solar flow return Cold water expansion valve Controller EE should discharge away from the Plinth base of heater and footings Five way Valve Chapter 6 System Types 61 Figure 6 3 Forced circulation system evacuated tube collectors installation diagram ylomadid ser u1n19J MO J 1e OS paje n
60. d include a b E d e f 9 h the climate zone of the site and possibility of i shading ii frost and freezing iii wind iv dust v hail vi corrosion and scaling the ambient air temperature the cold water temperature the availability of space and pitch of a suitable north facing roof the presence and location of an existing hot water service the available energy sources e g gas or electricity the householder s hot water usage the householder s budget 1O Chapter 2 Design Principles 2 2 Legislation 2 2 1 Building permits Regulations concerning building permits for roof mounted collectors and tanks and modifications to strengthen the roof structure may vary from state to state The installer should ensure that all applicable building permit requirements have been identified and that permits have been granted before starting the installation 2 2 2 Licensing 2 2 2 1 Water connections All water supply connections in solar hot water systems must be made by an installer holding the relevant state or territory plumbing licence 2 2 2 2 Gas connections Where the system is connected to a gas booster all gas connections must be made by an installer holding the relevant state or territory gas fitting licence 2 2 2 3 Electrical connections Where the system is connected to an electronic controller or general power outlet all electrical connections must be made by a person holding the
61. d territory rebates can be found on the following websites State or territory rebate information websites New South Wales www environment nsw gov au rebates ccfhws htm Queensland www cleanenergy qld gov au queensland_solar_hot_water_program cfm Victoria WWW resourcesmart vic gov au for households rebates html Northern Territory WWW powerwater com au Western Australia www1 home energy wa gov au pages subsidy asp Australian Capital Territory www thinkwater act gov au tuneup_rebates shtml South Australia www dtei sa gov au energy rebates_and_grants solar_hot_water Chapter 12 Government Incentives 119 120 _ Chapter 13 EZ 4 PS 15 1 General The Australian Government and state and territory governments are working together to phase out greenhouse intensive electric water heaters Commencing in 2010 electric water heaters will be phased out across Australia in new and existing detached houses terraced houses town houses and hostels For hot water installations in new homes requirements are specified in the Building Code of Australia and will be regulated through state and territory building regulations Installations in existing homes will be regulated through state and territory plumbing regulations The implementation of the program in 2010 Stage 1 is being undertaken on a state by state and territory basis with each participating state responsible for determining its commencement date eligibilit
62. die Hediand j 21 May 18 15 Rockhampean m 5 Carnarson E BRISBANE d Lo seraldtan Mo Pita Cola Hartexui i Codina PERTH Pret F STONE i pr Albi Lincoln a L I H i Average daily solar exposure u Annual Cape Grm i SY Helern e mirahan llas on 8 rs ia eer eS eet Preyectian Laentiert cordate wer hdc OLA emnt nec was aarda paroles 10 0 VE HOBART Cosma ania DEN Source Bureau of Meteorology www bom gov au Table 1 2 shows by month the average daily solar exposure in megajoules per square metre of cities around Australia Table 1 2 Average daily irradiation by month of Australian cities MJ m Annual Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec average Adelaide 27 24 18 12 6 6 6 9 12 18 24 27 15 8 Alice 27 24 24 18 15 12 15 18 21 24 2 24 20 3 Springs Brisbane 24 21 18 15 12 9 12 15 18 21 21 24 17 5 Cairns 21 21 18 15 15 12 15 18 21 21 21 24 18 5 Canberra 24 2 18 12 9 6 9 12 15 18 2 27 16 0 Darwin 21 18 21 21 18 18 21 21 24 24 21 24 21 0 Hobart 2 18 12 9 6 6 6 9 12 15 2 21 13 0 Melbourne 24 21 15 9 6 6 6 9 12 18 21 24 14 3 Perth 27 24 2 18 9 9 9 12 15 21 24 50 18 3 Sydney 21 21 15 12 9 9 9 12 15 18 21 24 15 5 Source Bureau of Meteorology www bom gov au Chapter 1 Solar Radiation 5 Factors affecting available solar irradiation are a b e d e f 9 latitude shading rainfall cloud cover orientation of sol
63. dual trading Householders can create the RECs themselves in an internet based registry system called the REC Registry It is up to the householder to find a buyer and to sell and transfer the RECs in the REC Registry More information is available from the Office of the Renewable Energy Regulator on 02 6159 7700 or at www orer gov au The Office of the Renewable Energy Regulator has a register of approved solar water heaters and heat pumps and a list of the RECs generated by them in different climate zones This information can be found at www orer gov au swh register html 12 2 2 Rebates Rebates are an economic incentive to reduce the upfront cost of solar or heat pump hot water systems To encourage the installation of solar and heat pump hot water systems rebates are available at federal and state government levels This section provides information on where to find current state and federal rebates Information provided is accurate at the time of writing and may be subject to change at short notice It is suggested that installers check appropriate state and federal programs regularly for details 12 2 3 Australian Government rebates At the time of writing the Australian Government offers rebates for both solar water heater and heat pump systems Full guidelines and eligibility criteria are available at www climatechange gov au 118 Chapter 12 Government Incentives 12 2 4 State and territory rebates Information on state an
64. e 2 11 Advice on a suitable system for a ring main installation should be sought from manufacturers Figure 2 11 Ring main layout Storage tank Ring main a Living Bed Lounge 24 Chapter 2 Design Principles 2 7 3 Pipework exceeding 20 metres Where pipework length exceeds 20 metres or is supplying multistorey dwellings a hydraulic consultant will need to advise on the size of the pipes and on the pump requirements for appropriate water circulation 2 7 4 Ring main pump Installers should consider the following issues when selecting a pump a temperature of the water b water pressure and velocity speed required c friction losses e g number of 90 bends in pipework d pipe length and diameter Pumps should be correctly sized as friction losses can adversely affect the performance of the system The manufacturer should be consulted for an appropriate pump for the chosen system Chapter 2 Design Principles 25 26 Chapter 3 A a 5 1 General Solar collectors are the core component of the solar hot water system Solar collectors absorb the sun s energy and heat water by means of a direct heating the water is heated as it circulates through the collectors or b indirect heating another fluid such as glycol anti freeze is heated and transfers heat to the water in the storage tank by heat exchange Solar collectors must be designed and constructed in accordance with AS NZS 271
65. e difference is reduced This temperature difference varies between solar hot water systems but is usually between 7 C and 10 C 2 6 1 3 Under temperature protection frost protection The controller can detect when the water in the collectors drops to a predetermined temperature usually 3 C to 5 C When this occurs the pump will be turned on to circulate warm water from the storage tank through the collectors to prevent freezing When the temperature reaches 7 C to 10 C the pump will be turned off 22 Chapter 2 Design Principles 2 6 1 4 Over temperature protection overheating The controller can use the sensor at the storage tank to detect when the temperature of the water is too high In vitreous enamel storage tanks over heating can damage the lining As water only needs to reach 60 C the controller can be set to turn the pump off if the temperature exceeds 70 C see section 35 5 Over temperature protection 2 6 2 Solar collector pump In most cases manufacturers will include or recommend a pump for their solar hot water system Only those pumps provided or suggested by manufacturers should be installed 2 6 5 Pump location Some storage tanks are built with the pump enclosed at the bottom or on the outside casing of the tank Other storage tanks may need to have a pump installed on the flow line between the storage tank and the collectors In both cases the pump is operated from mains electricity though some pumps
66. e tank This is due to air build up when the water is drained from the collectors into the storage tank Figure 5 5 shows an air bleed valve assembly as it is commonly installed at the collector Figure 5 5 Air bleed valve assembly 4 Air bleed valve cap must be open Air bleed valve must point to the sky Collector connection at 90 from the horizon Temperature sensor to electronic controller Sensor well N Hot water return to tank Cross piece 58 Chapter 5 Pipework amp Fittings Chapter 6 A a wu CE RES j x E id 6 1 Close coupled systems Close coupled systems comprise the solar collectors mounted together with the tank on the roof Water supplied to the storage tank from the main cold water inlet flows to the bottom of the solar collectors The water is heated by the collectors and by thermosiphon flow the hot water rises to the top of the collectors and back to the storage tank via a short return pipe on the opposite side of the storage tank The hot water from the upper section of the tank is then supplied to the tempering valve where it is mixed with cold water from the main cold water inlet and then distributed to the household fixtures A thermostat controls the water storage temperature and if needed will boost the water temperature by electricity or gas Figure 6 1 shows a close coupled thermosiphon sy
67. eas with corrosive water the anode may need replacing every few years If the water quality is good and the hot water use low then an anode may last up to 15 years In those areas anodes should be inspected every five years When replacing an anode the manufacturer s specifications must be followed to ensure that the correct anode is installed 10 5 5 Heating elements electric boosting Scale build up on electric heating elements can cause them to overheat and fail Where scale is a known problem action should be taken before the element fails so as to not interrupt the hot water supply Longer elements that reduce the heat inside them as scale forms are available Those elements have an increased longevity 10 4 Sediment Sediment build up in the bottom of the storage tank and at the bottom header of the solar collectors is not uncommon and small quantities of sediment are not necessarily a problem However where the build up of sediment is significant it may cause corrosion or odours if it contains organic material that decomposes This may occur in areas where the water quality is poor or where rainwater is used to supply the solar hot water system To remove sediment drain the storage tank of all but a small quantity of water disconnecting pipes and wires from the electrical system The tank can then be shaken to stir the sediment inside The sediment is then drained from one of the lower connections Care must be taken to
68. ed to the roof structure as per the manufacturer s recommendations Storage tank DO 00000 Pressure and temperature relief valve is installed on water storage tanks if applicable Tanks connected in parallel are plumbed for balanced flow conditions Cif applicable Tanks are installed so they promote effective stratification if applicable Adequate access is allowed for maintenance If tank is to be roof mounted the roof is structurally strong enough to carry the weight of the full tank Storage tank is full of water before the system is turned on Flow and return pipe work O O O Suitable pipework sizes have been chosen for solar flow and return No plastic components or pipework are used on the solar flow and return A high quality temperature rated UV and weather protected thermal insulation has been installed on solar flow and return pipes Valves and fittings O O 00000 Pressure limiting device is installed if applicable Temperature limiting device is installed to prevent scalding Non return valve is installed if applicable Expansion control valve is installed if applicable Freeze protection device is installed if applicable Stagnation or overheating protection device has been installed if applicable Thermal sensor cables are not in contact with the flow and return lines Chapter 9 Installation Considerations 107 High temperature pressure C Consideration has been given to the exp
69. eenhouse hot water system If it has failed within the warranty period There are temporary arrangements available in Queensland that are intended to give the consumer time to consider which low greenhouse gas hot water system to install The website www dip qld gov au sustainable housing electric hot water system replacement html provides up to date information 13 3 2 South Australia South Australia has introduced requirements for water heaters where construction work is required such as in new homes or renovations requiring development applications DAs For applications lodged after 1 May 2009 a number of requirements separated by building classification need to be followed Class la and 1b in metro or regional South Australia by postcode o Solar hot water electric boost heat pump o Solar hot water gas boost any system o Gas storage instantaneous minimum 5 stars Class 2 single apartment o Solar hot water electric boost or heat pump any system o Gas storage instantaneous gt 2 5 stars o Solar hot water gas boost any system Class 2 multiple apartments exempt Class 1 remote South Australia Class 1 Metro where heaters are either inside or outside in shed or garage and less than 3m from neighbouring windows and doors Same as for as Class 2 o Solar hot water electric boost or heat pump any system o Gas storage instantaneous gt 2 5 stars o Solar hot water gas boost any syste
70. eir budget The choice is not limited to gas where a home has access to piped reticulated gas Householders can choose from any of the low emission technologies including solar heat pump or gas include some exemptions These are yet to be finalised but will apply where appropriate alternative technologies are not yet available or in situations where there are significant additional costs Chapter 13 Requirements for New amp Existing Homes 123 15 5 Complementary state programs new and existing buildings 13 3 1 Queensland The Queensland Plumbing and Wastewater Code states that as of 1 January 2010 existing houses and town houses Class 1 buildings located in a natural gas reticulated area must install a greenhouse efficient hot water system i e gas solar or heat pump when the existing electric resistance system needs replacing Householders will not need to replace existing electric resistive water heaters that are in good working order This follows action by the Queensland Government to ban installation of electric resistive water heaters in all new houses and townhouses Class 1 buildings only which came into effect on 1 March 2006 As of 1 January 2010 in existing Class 1 buildings hot water must be supplied by either a solar hot water system a heat pump system a gas hot water system with an eneroy rating of at least 5 stars The electric hot water system does not have to be replaced with a low gr
71. ensure that the tank is not damaged and that the maintenance person is not injured A second person may be required to provide assistance Chapter 1O Maintenance 111 112 Chapter 11 E 4 PS 11 1 General If the storage tank fails and the hot water supply cannot be restored on the same day a temporary electric hot water service can be installed A small capacity electric storage tank powered by a general power outlet can easily be secured to a hand trolley and wheeled to the location of the existing storage tank and connected to the existing pipework Figure 11 1 This solution may also give the householder time to consider an alternative hot water service if the existing system is an electric hot water service Figure 11 1 Trolley mounted temporary hot water supply Hand trolley j Temporary hot water outlet to existing hot water supply Small capacity k electric storage tank Support straps mm ud Temporary cold water inlet from existing cold water supply 240 volt power supply 114 Chapter 11 Temporary Hot Water Installations Chapter 12 A a 12 1 General The following information on government incentives is current at the time of printing of this handbook Please refer to Government websites for the most up to date information 12 2 Rebates and renewable energy certificates for solar hot water installations Two types of incentives are offered to householders t
72. ers Western Australia new homes only www buildingcommission wa gov au bid 5StarPlus aspx 122 Chapter 13 Requirements for New amp Existing Homes 15 2 2 Stage 2 During 2012 the phase out will be extended so that greenhouse intensive water heaters will no longer be able to be installed in all Class 1 dwellings and new Class 2 buildings with access to piped reticulated gas except where an exemption applies 15 2 5 Post 2012 For new apartments without access to piped reticulated gas the phase out will occur between 2012 and 2015 depending on further investigation of the feasibility of low emission water heating options for such buildings Table 13 4 General schedule of phase out Building class New Existing 2010 Dwellings in a piped Class 1a and 1b 2010 All dwellings reticulated gas area 2012 All dwellings Class 2t 2012 New dwellings with Esen pi access to piped gas Class 1 consists of detached houses terraces and town houses and hostels Class 2 includes apartments and flats State and territory government programs will not force any households to replace an existing operating hot water heater The phase out will apply to new buildings and where the hot water system in an existing building breaks down or ages and needs to be replaced with a new system give home owners options Home owners will be asked to choose the low emission alternative that best suits their home their climate and th
73. eting can also be used to stop small equipment or tools falling into the roof cavity or puncturing ceiling material Employer installer obligations include a ensuring all staff have received adequate training for any work that is carried out b providing a safe means of raising and lowering equipment material or debris on site c where possible creating a secure physical barrier to prevent objects falling from buildings or structures in or around the site d where it is not possible to create such a barrier introducing measures to stop the fall of objects this could include creating a platform with scaffolding a roof protection system or positioning a toeboard on a guardrail e ensuring all workers wear personal protective equipment to minimise the risk from falling objects Control and safety measures include creating a perimeter fence on top of scaffolding around a house during installation this may be practicable when a house is having solar or heat pumps water heaters installed during the construction phase This offers a work platform for plumbers and protects workers from falling objects 8 12 Working with heavy equipment As a general guideline a person standing should not lift anything that weighs more than 16kg without mechanical assistance or assistance from other people Local state or territory guidelines differ but mechanical lifting equipment is recommended for all objects more than 16kg to 20kg Providing adequ
74. fluid having an aperture that can be wholly or partially closed by the movement relative to the seating of a component in the form of a plate or disc door or gate piston plug or ball or flexing of a diaphragm Expansion control valve A pressure activated valve that opens in response to an increase in pressure caused by the expansion of water during the normal heating cycle of the water heater and which is designed for installation on the cold water supply to the water heater Float valve A valve for controlling the flow of a liquid into a cistern or other vessel which is operated by the movement of a float Frost dump valve A valve that opens at low temperatures about 4 C to allow water to run through the collectors to prevent freezing Chapter 14 Glossary 155 Isolating valve Any valve for the purpose of isolating part of a water system from the remainder Non return valve A valve to prevent reverse flow from the downstream section of a pipe to the section of pipe upstream of the valve Pressure limiting valve Pressure temperature relief PTR valve A valve that limits the outlet pressure to the set pressure within specified limits only at inlet pressures above the set pressure A spring loaded automatic valve limiting the pressure and temperature by means of discharge and designed for installation on the hot side of a storage water heater Temperature relief valve A temperature
75. han gas storage and instantaneous systems In these types of installations solar collectors can be mounted on the roof without the need for an additional storage tank Depending on whether the existing storage tank has solar flow and return connections the installation may be exactly the same as a regular split system If the storage tank has only one cold inlet and one hot outlet a five way connector will need to be fitted which will provide the required connections for the flow and return lines to the solar collectors Figure 6 15 shows a five way connector fitted to the cold water inlet of an existing storage tank Figure 6 15 Five way connector top view Cold water inlet N 5 way connector Dip tube Hot water return from collectors Thermal sensor well Cold water flow to and from storage tank Cold water flow to pump f r for circulation to collectors In the five way connector cold water flows through one connection supplying the storage tank The circulation pump then draws water from the storage tank through another outlet on the connector and circulates it to the solar collectors where the water is heated The heated water returns to the storage tank through the hot water inlet in the five way connector and is then distributed to the middle of the tank via an upward turned dip tube Figure 6 16 shows a five way connector fitted to an existing electric storage tank 76 Chapter 6 System Types Figure 6 16
76. he array of tubes and does not include the gap between tubes The area of tube arrays with a parabolic reflector behind the tubes is the area of parabolic reflector Commissioning ep uem f ons a cz tw The process of ensuring that all component parts of a total system function as they should and that the system is adjusted for optimum performance under all normal operating conditions Commissioning is the last part of an installation prior to hand over to the owner Compressor An electrically driven pump that moves refrigerant around a heat pump circuit to transfer heat Condenser A heat exchanger consisting of either a flat plate with tubes attached or grille like fins and tubes In a refrigerator this becomes hot and dumps heat collected from the food to the air outside This is part of all heat oump systems for transferring heat from the air to water Convection Convection is the transmission of heat within a liquid or gas due to the bulk motion of the fluid The rising of hot water from the bottom to the top of a saucepan as it is heated is one example This occurs because the particles of water bump against one another more vigorously as they are heated and push themselves further apart making the water less dense and hence lighter 150 Chapter 14 Glossary Corrosion Deterioration of metal The metal combines with other elements to form a salt of the metal Rust is the corrosion produc
77. he collector In close coupled systems the position of the collectors will be relative to the location of the storage tank see section 6 1 The lower support straps supplied with the solar collectors should be affixed to the retaining bracket at approximately 200mm from either end see Figure 9 1 Figure 9 1 Collector straps mounted to a tile roof Upper retaining bracket screwed into rafters Upper collector support straps screwed into rafters Tile battens Lower retaining bracket screwed into rafters 30mm higher on the hot water outlet side Solar collectors Lower collector support straps attached 200mm from the outer edge of the retaining bracket On tiled roofs support straps will need to be screwed firmly onto the rafters roof structure not tile battens This will require the removal of a section of tiles at each strap to expose the rafters The support strap should be bent to run flush with the rafters Figure 9 2 and Figure 9 3 Chapter 9 Installation Considerations 97 Figure 9 2 Collector strap moulded to rafter tiled roof am e po ha e E pes tad Collector support straps moulded around the roof structure and tucked under upper tile Tile battens Lower retaining bracket screwed into rafters 30mm higher on the hot water outlet side Collector support straps attached 200mm from the outer edge of the retaining bracket lt Rafters Figure 9 3 Collector strap mounted
78. he purpose of the risk assessment or safety audit is to enable the installer time to inspect the site and assess the likely hazards Whilst undertaking this risk assessment it is usual to plan how to safely undertake the job The risk assessment considerations for traditional hot water installations and heat pump and solar hot water installations are very similar but the installation of solar and heat pump hot water systems also involve some specific risks This section aims to highlight the major safety concerns relating to the installation of heat pumps and solar water heaters This list is not comprehensive and issues can be different from site to site so installers must still carry out a full risk assessment for each and every site before commencing work 8 4 Working at heights Installers should know and work according to relevant requirements for lifting and working at heights In addition to general occupational health and safety and work safety legislation the National Code of Practice for the Prevention of Falls in General Construction deals with safe work practices when work is undertaken at heights of more than 1 8 metres Installers can contact their local Workcover or use the links provided in this reference guide to check for existing or updated instructions or standards The National Code of Practice can be accessed at www safeworkaustralia gov au swa AboutUs Publications NationalStandards NationalCodeofPracticeforthePreventi
79. ially improves the performance of the tempering valve Figure 5 4 Location of tempering valve Tempering Valve Z3 Tempered Water to House Cold Water Inlet Chapter 5 Pipework amp Fittings 57 5 5 2 Location of the tempering valve The tempering valve should be located as close as practicable to the storage tank to ensure that the whole house can access tempered water Tank positioning see Chapter 4 Storage tanks is important as the tempered water will continue to lose heat as it flows to the various outlets For this reason it is equally important that the tempering valve be installed as central to the main points of tempered water use as possible NOTE A tempering valve reduces the risk of scalding and under AS NZS 3500 4 2003 must be installed for all new and replacement water heaters It is the responsibility of the installer to check local regulations as requirements for installing tempering valves in domestic and commercial hot water systems can vary between jurisdictions Under AS NZS 3500 4 2003 the tempering valve must be installed in a position which is readily accessible 5 6 Air bleed valve The air bleed valve is installed in many split pumped systems to allow air generated within the collectors to escape This valve is installed at the highest point of the collectors at the hot water return line The exception to this rule is in drain back systems where this valve is situated on the top of the storag
80. ials 5 21 Pipework 5 2 2 Fittings 5 3 Pipework size 5 5 Diameter 5 3 2 Length 5 5 2 General 5 5 2 2 Drain line from PTR valve 5 3 2 5 Tempered water line 5 4 Insulation 5 41 Minimum insulation requirements 5 4 1 1 Climate region 5 41 2 Minimum insulation diameter 5 41 5 Insulation construction 5 4 2 Pipework requiring insulation 5 4 5 Insulation considerations 5 5 Tempering valves 5 5 General 5 5 2 Location of the tempering valve 5 6 Air bleed valve IV Contents 27 28 28 28 29 29 30 30 5 31 32 32 35 35 35 35 36 36 39 39 39 43 44 44 44 45 45 46 47 49 51 52 52 52 52 52 52 53 53 53 53 53 53 54 55 55 B5 56 56 56 58 58 6 System Types 59 6 1 Close coupled systems 60 6 2 Forced circulation systems split or pumped systems 61 6 5 Gravity feed systems remote storage 63 6 4 Drain back systems 64 6 5 Heat pump systems 66 6 5 1 General 66 6 5 2 Heat pump compressor 66 6 5 3 Heat pump storage tank 66 6 5 4 Heat pump operation 67 6 5 5 Rate of heating 68 6 6 Retrofit systems 71 6 6 1 Existing gas storage system 71 6 6 2 Existing gas instantaneous system 74 6 6 3 Retrofit to existing electric storage tank 76 7 Boosting 79 7 1 General 80 7 2 Electric boosting 81 7 21 Electric storage 81 7 2 1 1 Off peak tariffs 82 721 2 Day rate tariffs continuous supply 82 7 3 Gas boosting 82 731 Gas storage 82 7 5 2 Gas instantaneous 83 7 4 Solid fuel boosting 84 7 4 1 Installation c
81. in cyclone prone areas a mounting sheet with additional support brackets is affixed to the roof structure on which the collectors are mounted Figures 9 6 to 9 8 show a typical cyclone mount for flat plate collectors Because the configuration of cyclone mounts may vary from manufacturer to manufacturer they should be installed in accordance with their specifications Figure 9 6 Cyclone mount side profile Roof material FA Support ue bracket Collector J Support bracket lt Mount sheeting Rafter Roof battens Figure 9 7 Cyclone mount top profile Support Support Support bracket Collector bracket Collector bracket FA a 2 a N i P ai Rafters Roof batten 102 Chapter 9 Installation Considerations Figure 9 8 Cyclone mount detail QQ ka i inen c X im ha Collector Mounting N bracket Mount sheeting Roof ES Y grommet Roof battens Mounting screws Rafter 9 2 2 Mounting tanks 9 2 2 1 Roof mounted tanks Tanks can be either integrated or remote stand alone however regardless of tank location there must be sufficient access for maintenance including to replace sacrificial anodes Interior tanks must be placed on a safe tray that drains to the outside of the building or to the floor waste If the system is gas boosted ventilation must be sufficient to prevent the build up of exhaust gases Exterior tanks should always be insta
82. ing a provide a workplace and safe system of work so employees are not exposed to any hazards b give employees training information instruction and supervision to allow them to work in a safe manner c consult with their employees about safety issues d provide protective clothing and equipment to protect employees where it is not possible to eliminate hazards from the workplace oo CE Kd j x x ta 88 Chapter 8 Occupational Health amp Safety Employers also need to develop policies for each workplace or each job site to make sure that they maintain a safe standard of work This is done through a hazard identification risk assessment and control processes b specified safe work procedures c monitoring performance and reviewing control measures regularly d consulting with employees e training programs covering how to report hazards hazards relevant to each worker and how to access health and safety information that the law requires employers to provide f maintenance programs g a system for reporting hazards or important safety information h emergency rescue procedures This is as vital for solar water heating and heat pump installations as for any other workplace activity 8 5 Risk assessment Installers must comply with local regulations and undertake an on site risk assessment or safety audit prior to beginning the installation of a solar or heat pump hot water system T
83. ing Thermal sensor lead to collector Gas supply Power lead to outlet Gas burner 82 Chapter 7 Boosting 7 5 2 Gas instantaneous As with the electric boosted instantaneous unit gas boosting does not occur inside the tank An in line gas instantaneous unit is fitted between the tank and the hot water pipework into the building This unit is usually mounted directly onto the storage tank but may also be separately mounted to a wall The solar hot water system is used to pre heat the water before it flows through the instantaneous unit The gas burner will only ignite if the water temperature is not at the required temperature 60 C otherwise it will bypass without additional boosting Figure 7 5 shows a gas instantaneous boosted storage tank Figure 7 5 Gas instantaneous boosted storage tank Flue outlet Anode cap Clearances to comply with AS 5601 v D ST Booster pump controller housing Storage Tank Hot water return from solar collectors Thermal sensor lead to collector im Hot water outlet gas booster Bm PTR valve Instantaneous gas booster tank or wal mounted Boosted hot water outlet to tempering valve Tempered water to interal fixtures Tempering valve Gas supply P d Cold water flow to solar collectors a PTR drain line Cold water Inlet Solar transfer valve optional Chapter 7 Boosting 83 7 4 Solid fuel boosting
84. int of static line also known as the safety line or horizontal lifeline b energy absorber c inertia reel or fall arrest device d fall arrest harness e lanyard or lanyard assembly All systems differ so installers will also need to consult with the suppliers of their safety equipment about how to use and maintain their systems Installers are required by Commonwealth and state and territory regulations to ensure that the fall arrest harness is connected to a static anchorage point on the ground or on a solid residence or construction An anchor point needs to be carefully chosen to minimise the distance of a fall and to ensure that the line does not encounter snags obstructions or edges This can result in the fall safety system failing Installers are also required to make sure that the fall arrest system used does not create new hazards including trip hazards Fall arrest systems and harnesses can only be used by one person at a time They must never be used unless there is at least one other person present on site to rescue an installer after a fall In some cases two people will be needed for a successful rescue All fall arrest systems must comply with AS NZS 1891 Industrial fall arrest systems and devices 8 8 Roofs greater than 45 For a solar hot water installation where the roof pitch exceeds 45 the risk assessment also needs to take account of the additional difficulty associated with steep roof pitches Thi
85. ishwasher or washing machine A typical flat plate collector has a surface area of two square metres Table 2 2 shows the approximate number of collectors required for various sized households Table 2 2 Approximate flat plate collector requirements for residential households No of Daily hot water Approximate Approximate occupants demand litres flat plate number of flat collector area m plate collectors 1 2 120 2 3 m2 1 2 5 4 200 z 6m 2 3 5 6 300 6m2 Zy 2 4 3 2 Evacuated tube collectors It is recommended that one square metre of evacuated tubes be used per occupant and for each major appliance using hot water from the solar hot water system e g dishwasher or washing machine A typical 10 tube system has a surface area of 1 8m Table 2 3 shows the approximate number of evacuated tubes required for various sized households Table 2 3 Approximate evacuated tube collector requirements for residential households No of Daily hot water Approximate Approximate evacuated tube number of evacuated occupants demand litres collector area m tube collectors 1 2 120 1 8 3 6m 10 20 5 4 200 3 6 5 4m 20 30 5 6 300 5 4m 30 Chapter 2 Design Principles 19 2 5 Installation location 2 5 1 Location of storage tank The storage tank should be located as close as practicable to the main areas of hot water use the bathrooms kitchen and laundry This will minimise heat losses through the use of sho
86. ith the householder s electricity supply company In off peak boosting the booster cannot be turned on during the day if additional hot water Is required 7 2 1 2 Day rate tariffs continuous supply Electricity supply on a day rate tariff is charged at a higher rate than off peak however the hot water supply should not be affected because the electric booster will be available at all times 7 3 Gas boosting If the household is located in a natural gas reticulated area natural gas can be supplied to the booster by tapping into mains gas supply Alternatively if natural gas is unavailable an LP gas cylinder can be installed by a gas supplier or plumber 7 3 1 Gas storage Gas boosting in the storage tank occurs by means of a burner that is thermostatically controlled The burner will ignite when the water temperature drops to a pre defined temperature and it will then heat the water to 60 C Figure 7 4 shows the configuration of a gas storage tank Figure 7 4 Gas storage tank PTR Valve Hot water return from solar collectors Flue outlet Clearances to comply _ a Hot water outlet to ll tempering valve m i PTR drain line Anode Vitreous enamel tanks 4 Flue Cold water flow to solar collectors Outer casing ou Inner tank casing Cylinder High density tank insulation d Thermostat Cold water Inlet Electronic solar pump controller tank or wall mounted Gas control hous
87. ithin a storage tank with the hottest hot water at the top and the coolest water at the bottom of the tank SWH Solar water heater Tank Also referred to as a hot water cylinder or container TDS Stands for total dissolved solids TDS is measured in mg L though it was once measured in ppm parts per million of salt dissolved in water Thermosiphon True north vs magnetic north The natural convection of water around a pipe circuit such as between solar collectors and the storage tank above The heated water in the collector expands and becomes less dense It therefore rises to the highest point in the circuit the top of the storage tank Cold water from the base of the storage tank moves down to replace the heated water True north is the direction to the north pole In most places this is a little different to magnetic north being either to the east or west of magnetic north Tube In this book the word pipe can mean pipe or tube Strictly speaking pipe is measured internally and tube is measured externally To be technically correct we should not speak about copper pipe but rather copper tube because it is the outside diameter which determines its size Steel pipe and most plastic pipes are measured according to the internal hole size and so are pipes not tubes UV Ultraviolet light is found in sunlight gt q Lid e cz wr Valve s A device for controlling the flow of
88. k or wall mounted Note For more system diagrams see Chapter 6 System types Before retrofitting a pre heater split system to an existing storage tank installers should consider the following a Is the demand for hot water high If it is a second pre heater storage may be required b Is the system able to accept solar pre heated water c Is the homeowner happy having two storage tanks where the existing system is gas storage and aware of the costs of maintaining two storage tanks d Is there adequate space to install a second ground mounted tank near the existing storage tank if required e Where a close coupled system is installed is the roof I strong enough to bear the weight of the system full of water or ii able to be strengthened f Is there access to the system for installation and ongoing maintenance Chapter 2 Design Principles 17 2 4 System sizing 2 4 1 General When sizing a system both the solar collector area and tank storage must be sized according to the daily hot water needs of the household The actual hot water usage will vary from household to household but as a rule of thumb Australians use an average of 50 70 litres of hot water per day In solar hot water systems a larger well insulated storage tank is better than more collectors which will result in overheating of water The exception to this is the heat pump which rather than relying on storage operates more continuou
89. l
90. listed are used in this publication but are included for information regarding related plumbing activities Altitude angle The vertical angle between the horizontal plane and the sun s position in the sky or points along the top of any object that may cause shading on a collector Antifreeze solution Adding ethylene glycol or propylene glycol to water lowers the temperature at which the water freezes By adding sufficient glycol to the water in the solar collectors and preventing freezing the damage that can be caused by frost is prevented This is exactly the same technique used in motor cars to prevent damage due to freezing AS NZS Australian Standards and New Zealand Standards Boost energy Closed cell polymer Energy that is used to boost the temperature in the tank when solar energy is not available Closed cell polymer can be defined as a high density synthetic foam Unlike some packing foam used to pad products inside boxes where the cells of the foam are broken see through and filled with air open cell polymer the closed cell polymer is formed by tiny air or specialised gas filled oubbles that are compressed together to form a semi rigid piece of foam that is moulded to the desired specification in plumbing applications a tube that can encase pipework Collector area The net area of collector receiving solar energy With an evacuated tube collector the collector area is the plan area of t
91. lled on a concrete plinth according to manufacturers specifications The plinth must be level to prevent the unit vibrating and to prevent water entering the unit in wet conditions In close coupled systems the roof must be able to support the weight of the collectors and the tank when full which can be up to 7OOkg The integrity and load bearing rating of the roof should be checked by a structural engineer or builder against the manufacturer s specifications for the solar hot water system As a rule of thumb the tank should be positioned so that it is evenly supported by at least two rafters or trusses This should be confirmed on a site specific basis Strengthening existing roof structure If required the roof should be strengthened in accordance with the Building Code of Australia and local building regulations A structural engineer should be consulted on any roof modifications required Attaching tank to collectors close coupled In close coupled systems the tank is positioned into the upper retaining brackets fixed to the collectors so that pipes can be connected without stressing the joints Chapter 9 Installation Considerations 103 e e Gaa po x x pa Vea The support straps are affixed to the designated spots on the top of the tank and to the rafters roof structure not tile battens A section of tiles at each strap will need to be removed to expose the rafters The support strap should be bent to run fl
92. m See www energy sa gov au a 30372 for up to date information on the South Australian phase out program 124 Chapter 13 Requirements for New amp Existing Homes 15 4 Existing state programs new buildings only Table 13 5 Summary of requirements for sustainable housing rating systems in states and territories Area System Comments AUSTRALIA Building Code of On 1 May 2008 the requirement that alterations achieve Australia BCA 5 star rating came into effect in the Building Code of Australia 2008 www buildingcommission com au The new standard for renovations or relocations applies to the thermal performance of a home and does not require a solar hot water system In 2010 Australian governments agreed to increase energy efficiency requirements for all residential buildings to a minimum of 6 stars and to introduce new requirements relating specifically to hot water systems Transitional measures are to be introduced from May 2010 Website www abcb gov au go thebca aboutbca ACT ACT House Energy The ACTHERS program requires a minimum 5 star rating as Rating Scheme part of the current BCA requirements ACTHERS Website www actpla act gov au topics design_build NSW BASIX BASIX the Building Sustainability Index ensures homes are responsible for fewer greenhouse gas emissions by setting energy and water reduction targets for houses and units Since 1 October 2006 BASIX has applied to all new residential dwellings and a
93. main areas of hot water use the bathrooms kitchen and laundry 2 6 Circulating pump A circulating pump is used in systems to circulate the water from a ground mounted storage tank to the collectors 2 6 1 Pump controller functions A pump without a pump controller would continuously circulate water at all times of the day regardless of whether the water it is required or not A pump controller functions to operate the pump efficiently so that water is circulated through the system only when it requires heating Chapter 2 Design Principles 21 Figure 2 9 Typical pump controller Controller housing Tank or wall mounted Circulating pump Cold water flow to collectors Cold water inlet from storage tank IE a wax Controller circuit board Power supply cable Cold water temperature to general power outlet sensor to storage tank Hot water temperature sensor to solar collectors 2 6 1 1 Timer operation The controller can be set to operate the pump between certain hours of the day e g between Yam and 3pm 2 6 1 2 Differential temperature control The controller uses information from a sensor located at the hot water outlet on the collectors and one or more sensors on the storage tank When the controller detects that the storage tank temperature is lower than the temperature of the collectors it will engage the pump to circulate the water until th
94. mpressor Expansion Exhaust Fan Valve Air Vent Air Vent a A Expelled Cold Air Warm Air Flow Dip Tube Hot Water Outlet DN PTR Valve Cylinder Heated Refrigerant from Compressor Condenser Heat Exchanger 7 Outer Casing Insulation Cooled Refrigerant Return to Evaporator Anode Stratified Water PTR Drain Line Thermostat Cold Water Inlet gt S y Electric Element if required Non return Valve 6 5 5 Rate of heating The rate at which a heat pump heats water is determined by a number of factors which include a ambient air temperature b relative humidity c cold water inlet temperature d size of the storage tank Table 6 1 shows the average rate of heating for a 250 litre tank 68 Chapter 6 System Types Table 6 1 Heat pump rate of heating Ambient Litres of water per hour with a temperature C 25 C rise in temperature 55 124 50 111 ABE 98 20 85 152 65 10 53 S 42 O 54 57 29 10 27 Notes These figures are intended to illustrate the effects of higher ambient air temperature on the rate of heating compared to the effects of lower temperatures and do not represent actual heat pump heating rates These figures do not factor in relative humidity A higher relative humidity will mean a quicker rate of heatino Figure 6 9 Heat pump system showing clearances Clearances to manufacture
95. nal protective equipment to arrest the fall of a person According to national and state and territory regulations and guidelines fall arrest equipment is a type of personal protective equipment and should not be chosen unless other systems which provide a higher level of fall protection such as scaffolding or elevating work platforms are impracticable 90 Chapter 8 Occupational Health Safety 8 7 Fall arrest systems These are the most common options for those installing solar and heat pump water heaters Under national OH amp S regulations installers are required to use fall prevention systems type 1 or type 2 described above when working at heights unless it is reasonably impractical to do so However in most residential homes the installation period less than one day and the small area of roof that the installer will be working on mean that scaffolding platforms and perimeter screens are impractical options for solar water heater installations A fall arrest system is preferred in some special cases including where there is a chance a worker may fall through the surface of the roof due to fragile roofing material Fall arrest require significant skill to use safely and in the event of a fall it is likely that even when the system works correctly there will still be some physical injury to the user People using a fall arrest system must always wear head protection Fall arrest systems comprise a an anchorage po
96. nerated or used over one hour where power output or demand is one megawatt MW Equivalent to 1 000 kilowatt hours kWh Mg L Milligram per litre measuring concentration in water 132 Chapter 14 Glossary MPa A megapascal is one million pascals a measure of pressure MP52 Manual of authorisation procedures for plumbing and drainage products NASA National Aeronautics and Space Administration US Off peak or Electricity tariffs where supply is made available to an electric heating controlled tariffs OH amp S element by the electricity supply company during set off peak hours typically for about eight or nine hours Occupational health and safety ORER Office of the Renewable Energy Regulator Orientation angle The angle between the direction the collector faces and true north not magnetic north as read by a compass PCA Plinth Plumbing Code of Australia A concrete slab or step similar to a paver A common size is about 450mm x 450mm x 50mm thick They make an ideal base to go under a hot water storage tank Most hardware stores or garden shops stock them as stepping stones for paths pH pH is the negative logarithm of the hydrogen ion concentration in a solution If the solution is acidic there are many H ions If the pH is low 2 or 3 it is very acidic If it is 5 or 6 it is slightly acidic 7 is neutral Above 7 is alkaline Extremely alkaline is 14 maximum
97. njeJeduuo ypA OAJCA UJnj9J UON peisooq seb J TL En je ui Seg YE AJLA UONEJOSI M Y A Y A je au urelq Y i Y J9Jem pajesy Jejos 9AI929J Y A 0 e qeins Jayesy Jajem SALA H ld y yue a6eJo s 1 snoeuejuegjsur Dursix3 Y Jeyeou eJd ejos i Y A A E pe ae 1 E LN 1 li I I Bulysey Joo 4 1019111 Sl und ODS P d BUM 11 JOJO9UUOO pexyue p i Peele li 4eddoo ulus T xu wo MOJ JSJem PjOD sumy Duiusey joou uoisseJduJo NS Jeddoo uius Jn Ue 0 uln181 J9 eM 10H utu LULUQOS Y UW WWQOG gt UIUWWQOG gt Chapter 3 Solar Collectors 41 42 Chapter 4 A a 4 1 General Water storage tanks used in solar hot water installations must be designed and constructed in accordance with AS NZS 2712 2007 and AS NZS 4692 1 and they must be installed to the manufacturer s instructions where those instructions are not in conflict with AS NZS 3500 4 4 2 Water quality The quality of water can determine which type of tank to use in a solar hot water system Water quality is measured against numerous factors including pH a measure of the acidity or alkalinity of a solution TDS total dissolved solids and water hardness The collective levels of pH TDS and water hardness can significantly affect the life of a storage tank and even the entire solar hot water system 4 2 1 pH measurement pH is measured on a scale from O to 14 Table 4 1 Table
98. not rely on thermosiphon flow but rather is forced by a circulator circulating pump ep q TT e cz ww Water changes state between 4 C and O C It changes from a liquid to a solid and with that change it increases in volume expands Frost protection Techniques used to prevent damage to solar water heaters caused by the expansion of water as it freezes GPO General power outlet Gravity feed storage tank The tank is usually in the ceiling and the hot water runs to the outlets by gravity The tank is not pressurised Chapter 14 Glossary 131 Hardness Water in which soap refuses to lather is called hard The hardness is caused by calcium salts calcium chloride dissolved in the water It precipitates in water heating devices to form scale Heat exchanger A heat exchanger is a device to transfer heat from one fluid to another without the two fluids mixing In solar water heaters a heat exchanger transfers heat from a mixture of water and an anti freeze into the water in the storage tank heating it There is no mixing of the two fluids and it is just the heat that is transferred Heat pipe Heat transfer liquid fluid A fluid with a low boiling temperature is turned to a vapour by a heat source the sun The vapour rises up the heat pipe and gives off its heat to something water at a lower temperature and changes back to a liquid A fluid that carries transfers heat
99. ns System sizing 2 41 General 2 4 2 Storage tank 2 4 5 Collectors 2 4 5 Flat plate collectors 2 4 3 2 Evacuated tube collectors Installation location 2 5 1 Location of storage tank 2 5 2 Location of solar collectors 2 5 3 Location of roof mounted tank Circulating pump 2 6 1 Pump controller functions 2 6 1 1 Timer operation 2 6 1 2 Differential temperature control 2 61 5 Under temperature protection frost protection 2 61 4 Over temperature protection overheating 2 6 2 Solar collector pump 2 6 5 Pump location Pipework design 2 1 Heat traps 2 7 2 Ring main 2 7 5 Pipework exceeding 20 metres 2 7 4 Ring main pump Q Contents ili 3 Solar Collectors 3 1 General 3 2 Types of collectors 5 2 Flat plate collectors 5 2 2 Heat pipe evacuated tube collectors 3 2 3 U tube evacuated tube collectors 3 3 Collector installation considerations 3 31 Orientation 3 3 2 True north and magnetic declination 5 5 2 Finding north 3 3 2 2 Adjusting for true north 3 3 3 Inclination Ctilt 3 3 4 Shading 5 5 41 Shading exceptions 3 3 4 2 Estimating shading 3 3 4 3 Actions to address shading 3 3 5 Mountings 5 5 6 Frost protection 3 3 7 Over temperature protection 3 3 71 Solar collectors 3 3 7 2 Hot water outlet from storage tank 4 Storage tanks 4 1 General 4 2 Water quality 4 2 1 pH measurement 4 2 2 TDS 4 2 5 Hardness 4 3 Types of tanks 4 4 Stratification 4 5 Heat exchange tanks 5 Pipework amp Fittings 5 1 General 5 2 Mater
100. nt of Climate Change and Energy Efficiency cannot accept responsibility for any errors and omissions contained in this information This section is intended as a guide to the principles of occupational health and safety as they relate to the domestic installation of solar water heating and heat pumps Specialist advice is recommended in particular for current health and safety requirements Installers need to be aware of a height hazard assessments b working at height procedures c assessment use wearing of correct height safety equipment harnesses et cetera d all other relevant safety factors specific to the work e occupational health and safety regulations codes Australian states and territories have different occupational health and safety legislation regulations codes and principles and they need to be observed for all solar water heating and heat pump installations State and territory specific requirements can be found online State Website related to occupational health and safety QLD www justice qid gov au ACT WWW Ors act gov au NSW WWW Workcover nsw gov au VIC SA WWW Workcover vic gov au www safework sa gov au WA www docep wa gov au WorkSafe NT www worksafe nt gov au TAS www workcover tas gov au 8 2 Installers obligations All employers and self employed people are required under Commonwealth state and territory laws to do the follow
101. ny alteration addition in NSW Water heaters listed in BASIX are solar gas or electric boosted electric heat pump gas instantaneous or storage with appropriate star rating Website www basix nsw gov au NT None Identified Check local responsible regulatory authority otherwise NT must comply with the BCA Website www nt gov au infrastructure bss strategies buildingcode shtml Chapter 13 Requirements for New amp Existing Homes 125 Area System Comments QLD Queensland Development Code QDC Queensland Plumbing and Wastewater Code QPW Website QLD Cleaner Greener Buildings Initiative Website QLD Sustainable Homes Website Part 7 New and replacement electric water heaters The QPW Code has been amended to set installation requirements for the replacement of electric resistance water heaters in existing houses Class 1 buildings located within a gas reticulated area This amendment commenced on 1 January 2010 From 1 January 2010 existing systems that need replacement must be replaced with a system that has a low greenhouse gas emissions impact i e gas solar or heat pump system Current requirements in ADC MP4 1 for the installation of gas solar or heat pump water heaters in new Class 1 buildings have also been placed in the amended QPW Code Source Building and Plumbing Newsflash 353 Issued 20 02 09 www dip qld gov au laws codes index php By the end of 201
102. o internal fixtures T EEEE y Y i Ji General M power GV outlet re PPP PPP Cold water inlet Z Electronic solar pump amp controller tank or wall mounted Before installing a forced circulation system installers should consider the following a the type and area of collectors to be used e g flat plate or evacuated tubes b whether a hot water circulation pump may need to be purchased if one is not built in to the storage tank c the heat losses due to longer pipe runs and that pipes will need to be appropriately designed and installed d whether there is access to the system for installation and ongoing maintenance Chapter 2 Design Principles 13 2 5 5 Gravity feed remote storage system considerations Figure 2 5 Gravity feed system Header Tank Storage Tank Float Valve Isolation Valve Collectors L RE uu 2 E LL LL LL B All D X LL LL LL L D ee Bll E m m gp Ek pn mc AA AAA E ay Hot Water P i Safe Tray Safe Drain Line to House i A i M Cold Water Inlet Flow and Return Lines to Boiler Solid Fuel Stove Before installing a gravity feed system installers should consider the following a Is the roof and ceiling space adequate to allow the tank to be mounted at least 500mm above the top of the collectors b Is the ceiling space sufficient to allow the storage tank and support stand to sit on a load bearing wall and span at least two rafters c
103. o encourage them to install low emission water heaters Renewable energy certificates RECs are available for the installation of solar and heat pump systems for new and existing homes The Australian Government and state and territory governments offer a range of rebates to people for the cost of purchasing and installing low emission water heaters Those rebates are in addition to RECs Solar and heat pump hot water systems are typically connected to mains electricity supply The tariff rate for this electricity supply will have an effect on the operating costs of these systems An important consideration in the design of a solar water heater or heat pump system is the electricity tariff the system will be connected to and the rate that will be charged 12 2 1 Renewable energy certificates RECs are available for eligible solar hot water systems or heat pump hot water systems for the total megawatt hours of eligible renewable energy generated by the system When installed a solar water heater or heat pump uses less electricity than a conventional hot water system This reduces the drain on the electricity grid and the amount of electricity produced by coal and other non renewable sources Solar water heaters and heat pumps are listed as a renewable energy technology under the Renewable Energy Electricity Act 2000 Under the Renewable Energy Target RET an installed solar water heater or heat pump is entitled to a number of RECS calc
104. ocal responsible regulatory authority Website WWW Wst tas gov au industries building 126 Chapter 15 Requirements for New amp Existing Homes Area System Comments VIC 5 star Website The 5 star standard for all new houses in Victoria came into full effect on 1 July 2005 This standard makes it compulsory for new houses to have a rainwater tank for toilet flushing or a solar hot water system If reticulated gas is available the solar water heater must be gas boosted www 5starhouse vic gov au WA 5 Star Plus Website In May 2007 Western Australia adopted the 5 Star Plus system which is an extension of the 5 star energy efficiency provisions of the Building Code of Australia This system is based around the Energy Use in Houses Code and the Water Use in Houses Code Energy Use in Houses Code Performance Requirement 3 Water Heaters A building s water heater systems including any associated components must have features that produce low levels of greenhouse gases when heating water Deemed to Satisfy Provision 3 Water heaters A hot water system must be either i a solar hot water system complying with AS 2712 2002 that has been tested in accordance with AS 4234 1994 and achieves a minimum energy saving of 6096 for a hot water demand level of 38MJ per day for climate zone 3 or ii a gas hot water system complying with AS 4552 2005 that achieves a minimum energy rating of 5 stars
105. of cavity Positioning the tank above the collectors is critical as it will prevent reverse thermosiphon flow which would cause cold water to flow to the storage tank leaving the hot water in the collectors Using thermosiphon flow the colder water in the tank flows to the bottom of the collectors where it is heated and then returned through the top of the collectors to the tank A feed tank usually a rainwater tank with a float valve control similar to that in a toilet cistern keeps the storage tank full This reduces the pressure in the feed tank to one atmosphere A safe tray with a drain line is fitted under the tank to prevent any spillage onto the ceiling Gravity feed systems can be boosted by a wood fire heater commonly referred to as a wetback see Chapter 7 Boosting Figure 6 4 shows a gravity feed remote storage system Figure 6 4 Gravity feed remote storage system installation diagram Header Tank Storage Tank Float Valve Isolation Valve Collectors pi Li i RE I i A x m um mx he EL EL NL E ee pg gx uc gm gw x EL cL AA JL E E D E E o o E NUM VEI Hot Water Na 1 Sale Tray 5afe Drain Line A to House m 4 p EN E Cold Water Inlet Flow and Return Lines to Boiler Solid Fuel Stove Chapter 6 System Types 635 Ww CE Gd m Ex ER d 6 4 Drain back systems A drain back system is similar to a standard forced circulation split system in that it com
106. of material the insulation should go through the penetration with the pipework as shown in Figure 5 2 Figure 5 2 Insulation continuity through roof penetrations Insulation continuing through roof ceiling penetration Ceiling cavity N EE Storage tank UV protected insulated flow and return lines Tempering valve Ns water to internal fixtures Cold water 5 5 Tempering valves 5 5 1 General AS NZS 3500 requires water to be heated to a minimum of 60 C in order to kill and prohibit growth of Legionella and other bacteria Water at this temperature is too hot for use in bathrooms and a tempering valve must be fitted to reduce the temperature to prevent scalding hot water being delivered to the fixture A tempering valve is a three way valve that mixes water from the hot and cold pipes to a pre defined temperature 50 C which is then taken through the third outlet to the fixture Figure 5 3 Tempering valves used in solar hot water installations should be high temperature solar rated valves 56 Chapter 5 Pipework amp Fittings Figure 5 3 Tempering valve Hot water from tank Flow direction indicator IF d AN Temperature adjustor sits below cap Water inlet indicators 50 tempered water to fixtures Cold water n from mains Equal water pressure from the cold and hot water supplies makes for better operation of the system and espec
107. of the Environment Water Heritage and the Arts Vill Preface Introduction The Australian Government and state and territory governments are committed to working together to phase out inefficient electric hot water systems Currently 50 of Australian households generate hot water using electric hot water systems Electric hot water systems are less energy efficient than other low emission technologies and in many cases have higher running costs than more energy efficient options The installation of low emission hot water systems will not only reduce the greenhouse gas emissions produced by the operation of hot water systems but also potentially save householders money on their energy bills Low emission technologies such as solar heat pump and efficient gas systems are two and a half to three times more efficient than conventional electric storage water heaters Householders should benefit from energy savings if they know which appliance best suits their circumstances and if plumbers and installers are trained in how to install low emission water heaters With the phase out of electric storage water heaters in mind this reference guide aims to a provide plumbers builders architects and engineers with i up to date technical details for the practical installation of solar and heat pump hot water systems ii information on best practice occupational health and safety iii data on available solar radiation iv hot w
108. old water supply 110 10 2 4 Non return valve 110 10 2 5 Isolation valve 110 10 3 Corrosion and scale formation 111 10 3 1 Valves 111 10 3 2 Sacrificial anodes 111 10 3 3 Heating elements electric boosting 111 10 4 Sediment 111 11 Temporary Hot Water Installations 13 11 1 General 114 12 Government Incentives 115 12 1 General 116 12 2 Rebates and renewable energy certificates 116 for solar hot water installations 12 21 Renewable energy certificates 116 12 2 2 Rebates 118 12 2 5 Australian Government rebates 118 12 2 4 State and territory rebates 119 V Contents 15 Requirements for New amp Existing Homes 13 1 General 13 2 Phase out of electric water heaters 15 21 Stage 1 15 2 2 Stage 2 13 2 5 Post 2012 15 5 Complementary state programs new and existing buildings 13 3 1 Queensland 15 5 2 South Australia 13 4 Existing state programs new buildings only 14 Glossary 15 Australian Standards amp Guidelines 16 Resources 121 122 122 122 123 123 124 124 124 125 129 137 139 Contents VII Preface The Solar and Heat Pump Hot Water Reference Guide is a resource to assist plumbers in installing solar and heat pump hot water systems This guide is part of a training program for plumbers being rolled out under the National Framework for Energy Efficiency and the National Hot Water Strategic Framework The Solar and Heat Pump Transitional Plumber Training Program is a joint initiative of the Australian
109. onofFallsinGeneralConstruction htm State and territory governments also produce information guidelines and codes of practice for working at heights and working in or on roofs As a general guide to the risks involved in working at heights the following factors should be considered a The surface of the roof is it unstable fragile or brittle or slippery is it a combination of different surface types is it strong enough to support the loads involved does it slope more than 7 or is it heavily sloped more than 45 b The ground is it even and stable enough to support a ladder scaffold or work platform if necessary Chapter 8 Occupational Health amp Safety 89 co en kd be x xX bad o CE Kd bem x x ta c Scaffolding or work area platforms are these crowded or cluttered are they erected and dismantled properly and safely d Hand grips do workers working at heights have hand grips e Unsafe areas are there openings holes or unguarded excavation sites are there power lines close to the work area f Access and egress are there any obstructions or safety hazards in the entrance or exit routes for the work site g Lighting depending on weather and location is there sufficient light for workers to work safely this is especially relevant when working in roof cavities h Inexperienced employees are there inexperienced staff or installers on site who may be
110. onsiderations 85 3 Occupational Health Safety 87 8 1 General 88 8 2 Installers obligations 88 8 5 Risk assessment 89 8 4 Working at heights 89 8 5 Risk of falls 90 8 6 Three types of control measure safe operating procedures 90 8 7 Fall arrest systems 91 8 8 Roofs greater than 45 91 8 9 Brittle or fragile roofs 92 8 10 Other relevant Australian standards for working at heights 92 8 11 Falling objects 92 8 12 Working with heavy equipment 92 8 13 Roof security 93 8 14 Working with metal and collectors 93 8 14 1 Heat hazards 93 8 14 2 Metal hazards 94 8 15 Hazards for working outdoors 94 8 16 Site assessment 94 8 17 Maintenance and service 94 Contents V 9 Installation Considerations 95 9 1 General 96 9 2 Installation 96 9 21 Mounting collectors 96 9 21 1 Flat plate collectors 97 9 21 2 Evacuated tube collectors 101 9 21 5 Cyclone and high wind mounts flat plate collectors 102 9 2 2 Mounting tanks 103 9 2 21 Roof mounted tanks 103 9 2 2 2 In ceiling tank gravity feed 104 9 2 2 5 Ground mounted tanks 104 9 2 5 Roof flashings 104 9 2 4 Heat pump installation 105 9 2 5 Pumps and pump controllers 106 9 2 6 Thermal sensor cables 106 9 2 7 Electric booster element 106 9 2 8 Gas booster ignition 106 9 29 Heat pumps 106 9 210 Commissioning 106 9 3 Installation Checklist 107 10 Maintenance 109 10 1 General 110 10 2 Valves 110 10 21 Pressure temperature relief valve 110 10 2 2 Float valve 110 10 2 5 Expansion valve on the c
111. or glycol flows Individual tubes are made up of a copper heat pipe that contains a very small amount of water in a partial vacuum The heat pipe is encased in a hardened dark glass tube with an evacuated layer that absorbs the sun s energy traps it like a thermos flask and uses it to heat the copper heat pipe inside As the copper heat pipe increases in temperature the small amount of water inside vaporizes lt 30 C and rises to the top of the heat pipe into the heat exchanger in the manifold The cold water is heated as it flows through the manifold and at the same time cools the vapour inside the copper heat pipe where it condenses and falls to the bottom of the heat pipe The process is repeated thus creating a highly efficient thermal engine for transferring the sun s energy from the tubes into the water supply Figure 3 2 Typical heat pipe evacuated tube array Insulation Cold Water Inlet Heat Exc hanger a sE TN E a Wa la Po 1 ji le rj 4 j P P u aro wr de m EA LIP 1 Kama A V I Fa EL auc A P VN A ha A a NL a TD t ir w Et mq ry A a P i Ja E o i aw y E mj Hi J Zr 4 M Tq E A L L A j 1 2 q Me m ua b hs F N i Copper Manifold Hot Water Outlet vi Copper evacuated heat pipe Absorber fin heat transfer liquid 5 2 5 U tube evacuated tube collectors Evacuated U tube collectors look similar to regular evacuated tubes h
112. owever unlike regular evacuated tubes U tubes use direct heating principles to heat the water U tube evacuated tubes pass the water supply through the evacuated tube inside a U shaped copper pipe The sun s energy is absorbed heating the copper pipe and the water flowing inside Figure 3 3 Chapter 3 Solar Collectors 29 Figure 3 3 Typical evacuated U tube array Hot Water Out Cold Water In oe En E 4 Am EE Ar c r Termination Plug Absorber fin Copper U tube 3 3 Collector installation considerations 3 3 1 Orientation To produce the maximum quantity of hot water from the sun solar collectors need to face the sun directly for as long as possible throughout the day Collectors should face true north where possible or up to 45 east or west of true north Figure 3 4 Figure 3 4 Collector orientation 30 Chapter 3 Solar Collectors Notes 1 Collectors positioned 45 east or west of true north can suffer efficiency losses of up to 25 2 Some state regulations allow for higher orientation angles and should therefore be checked to ascertain the maximum orientation angle allowable e g Victorian regulations allow for orientations of 5O east and 75 west of true north A For solar water heater collectors AS NZS 5500 2005 recommends that the orientation of the collectors be e between 50 east and 70 west for Victoria between northeast 45 and nor
113. prises roof mounted solar collectors and a ground mounted storage tank This type of system usually operates using indirect heating a pump is used to circulate heat transfer liquid glycol to the collectors where it is heated and returned to the heat exchanger in the storage tank which heats the water The fundamental difference with a drain back system is that when the water temperature in the collectors is excessively high or nearing freezing point the circulating pump is switched off and the liquid drains down into a reservoir in the storage tank This prevents the collectors from overheating or freezing and is achieved by installing the return lines on a 5 decline to allow the heat transfer liquid to use gravity to drain down into the reservoir 64 Chapter 6 System Types Figure 6 5 Drain back system installation diagram uw UL gt ued ENS Quid 919120025 9 UildYH 19 011U09 duund Jejos 21u0J129 3 Jenno Jamod eeua c N WWOOE 002 LN V y EEE E m X ES 9 Ul J9 e M pJO2 EEE Y n Y N Y i ol Y A Y i Y UUWUL gt uoylne e20 uM 499y 0 i AL gt Buiquunid 19 ul 1972M pjoo A A ou ureJq i A N A A A i gt 5 4 SoJnjXiJ EuJ9 UI SALA H ld vi 0 Jajem pajadua P A n onen Buueduio A A A Josues JeBueuoxe 1eau OL eJnjejeduuo l i ulwwwoos gt A s u una pe 47 rr 3 M
114. pter 3 Solar Collectors 57 Techniques to address the hazard posed by frost include a Using glycol based anti freeze This is a common solution in heavy frost or snow areas b Using a frost dump valve mains pressure systems only Frost dump valves open up as the water temperature drops between 2 C and 5 C allowing warmer water to flow through the pipework and into the solar collectors to prevent freezing c Using a circulating pump A circulating pump can be activated when the water temperature drops to a certain level to circulate warmer water through the pipes to prevent freezing This is done via a temperature sensor in the collectors d Using a gravity drain back system which will drain the collectors of liquid when the temperature in the storage tank is higher than that of the solar collectors This means the collectors cannot freeze because there is no water in them to freeze e Using evacuated tubes The small volume of liquid in the heat pipe means that even if the liquid freezes it will not cause the pipe to burst Figure 3 11 Example of close coupled thermosiphon system using antifreeze REN Heat exchanger outer cylinder Stratification of water Heat is transferred to inner cylinder Glycol flow around inner cylinder Anode Vitreous enamel tanks Inner cylinder Outer casing Hot water outlet to tap or tempering valve High density tank insulation Anode cap Glycol ret
115. r 48 Chapter 4 Storage Tanks 4 5 Heat exchange tanks In frost prone areas or where the water quality is very poor a heat exchanger can be used to separate the potable water from the water circulating through the collectors In this type of tank a corrosion inhibiting antifreeze liquid such as glycol is circulated through the solar collectors and returned through the heat exchanger The heat is then transferred to the water in the storage tank by contact with the copper pipe Heat exchangers are commonly designed by integrating a an outer tank or jacket around the cylinder Figure 4 5 b a coil arrangement of copper pipework inside or around the cylinder Figure 4 6 Figure 4 5 Horizontal storage tank with jacket heat exchanger Heat exchanger Heat transfers to i linder High density aie Anode Vitreous f Hot water tank insulation enamel tanks Outer casing outlet to tap or tempering valve Cylinder Anode cap Hot water glycol return Cold water Inlet from solar collectors Cold water glycol flow to solar collectors Stratification of water lt p ec Edd m CD ex T ta Note This type of storage tank can also be manufactured as a vertical tank Chapter 4 Storage Tanks 49 Figure 4 6 Vertical tank with submersed coil heat exchanger Anode cap Anode Vitreous enamel tanks High density insulation Hot water glycol return Hot water ot wate from solar collec
116. r Inlet Hot water glycol from collectors i t i 1 e i l aw I MEM JI hat A Ly s i l f E i D LENS r JM a _ AMEN fo ee ee s TP NR 4 Lo a r H i A Ee eee Y A L4 Cold LL ater LS P rs FS _ gt ees F Stratification of water Sacrificial anodes are commonly used with vitreous enamel tanks and are usually constructed of magnesium with small percentages of manganese aluminium or zinc The purpose of the sacrificial anode as the name suggests is to increase the life of the storage tank by attracting the total dissolved solids in the water and corroding or sacrificing the anode rod instead of the storage tank 46 Chapter 4 Storage Tanks 4 4 Stratification Stratification is the layering of water at different temperatures within the water tank with hot water at the top and cold water at the bottom Stratification is caused by hot water which is less dense rising to the top of the tank Storage tanks are designed to minimise the mixing of hot water and cold water Solar collectors are more efficient when heating cold water thus excessive mixing of hot and cold water can reduce the efficiency of the solar system Some solar storage tanks are designed so that the inlet and outlet ports allow for a laminar flow of water entering and leaving the tank thus minimising turbulent mixing inside the tank In some cases cold water may be fed in
117. rature protection that is available including systems using a pump the pump controller will shut down if the water temperature is greater than 7O C thermosiphon systems if suitable low efficiency collectors can be used to minimise the high water temperatures arrestor valves are installed for temperatures gt 75 C Figure 3 13 shows an instantaneous gas split system with all valves 40 Chapter 3 Solar Collectors Figure 3 13 Instantaneous gas split system layout showing all valves pejejinsur uJnj9J MO Jejos pe1unou e amp M JO yug xXJowedid 1942m pop UE Saa 19 1011Ju09 duund pejeinsur IeJOS 91119913 POE Sul yue oBe10js Bunsixe Jo 1 u Joyem ules n us 09 0 S 99uuo2o MO 19 eM JO yiomedid Jojem peJjeduuos PI d Mi MERO u Quid 9 8 59uoo p nb 1 SALA UOI 2910Jd 1S0JJ lt ES l PE C r x Y Y a m Y Y u1u100 00c A EA J9I 9J JIV 9m JOSUBS E EEE EAS rr rr rr mee lt lt lt lt lt lt lt lt lt se we onen Buuedwey u X IN lt a F A I Y JeureJis our JO unu gt yla Auoyie 290 ui 49949 ME Buiquunid u Jayem pio A PA Hld SOPA jeusi i Iquiniq 1 ul pJoO SAJEA UOISUEAXO JOJEM pJoo 0 43 em pejedue L Mn A 19 1NO Jamod y A lt dUSUBS onen Bun eanssaJg jejeuec v eJ
118. rollers Many manufacturers have the pump unit wired into a standard power plug An electrician may be required to install a power point and if this is to be installed outdoors the unit must be rated for outdoor use The pump and pump controller must be connected to continuous tariff electrical supply to ensure that the pump and or controller can operate at any time of the day or night e g for frost protection A pump will generate some noise during operation It is good practice therefore to position the pump at least 1 2m away from bedroom windows 9 2 6 Thermal sensor cables Thermal sensor cables usually have a special additional coating on the first metre of cable at the collector to prevent interference damage from high temperatures The remaining cable should be attached to rafters or along the wall because contact with the flow and return pipework can interfere with the temperature reading cause the circulating pump controller to not operate properly and the system to fail from overheating or freezing 9 2 7 Electric booster element An electric booster element which is usually hard wired into a separate electrical circuit dedicated to the water heater can operate on either continuous or off peak tariff Any electrical connections to roof mounted solar water heating systems e g thermosiphon systems will require adequate waterproofing 9 2 8 Gas booster ignition A gas booster ignitor is usually connec
119. roof or ceiling when installing remote thermosiphon systems tank installed in a domestic roof space or a close thermosiphon system tank installed on rooftop Prior to lifting any equipment onto the roof or into the ceiling cavity the roof or ceiling must be checked to ensure it is strong enough to carry the equipment Control measures for roofs or ceilings that are insufficient to hold total equipment weight include a strengthening roof structures to hold system weight see installation instructions for details b locating system equipment over roof supporting framework only c locating collectors so they span at least two roof supporting trusses or trusses rafters to adequately support the collector weight d introducing weight bearing pathways within the ceiling cavity to ensure that all weight rests on trusses rafters support beams Any in roof tanks must be mounted over internal joining walls in accordance with the Australian Building Standard 8 14 Working with metal and collectors 8 14 1 Heat hazards Site and risk assessments for installations that involve the use of metals and glass need to consider the dangers from materials over heating and injuring workers Such risks are multiplied when solar hot water systems are installed because collectors are designed to become hot on exposure to solar irradiation This can occur even on overcast and cold days Measures to control the burn risks associated with working with me
120. rs Minimum Energy Performance Standard MEPS requirements and energy labelling AS 3814 2005 Industrial and commercial gas fired appliances and equipment SAA HB 9 1994 Occupational health and safety AS 1470 1986 Occupational health and safety 158 Chapter 15 Australian Standards and Guidelines Ma m A j g f u N x x Chapter 16 fe f Resources Australian Greenhouse Office 2004 Minimum Energy Performance Standards MEPS for Heat Pumps Report No 2004 17 National Appliance and Equipment Energy Efficiency Program Berrill T ed 2000 Solar water heating systems resource book Brisbane North Institute of TAFE available from www qtw com au Berrill T amp Blair A 2007 Solar water heater training course installation and user manual Australian Business Council for Sustainable Energy Duffie JA and Beckman WA 1991 So ar engineering of thermal processes John Wiley and Sons New York Foster JS 1991 Acceptance of solar water heaters by new householders in Queensland ISES Solar World Congress proceedings Denver Colorado George Wilkenfeld and Associates GWA 2005 Estimating household water heater energy use running costs and emissions Victoria report to Sustainable Energy Authority Victoria Lee T Oppenheim D amp Williamson TJ 1996 Australian solar radiation data handbook available from Australian and New Zealand Solar Energy Society Www anzses org Lloyd CR
121. rs specifications lt m gt in fro Hot water outlet p bedroom Tempering valve PTR valve Drain line Tempered water to internal fixtures a General power outlet ER Isolation valve wm i Non retu m valve w a L TA LA LA 200 300mm D gt Pressure limiting valve p Cold water inlet plumbing Check with local authority SS Kk Cold water expansion valve Y S L immi gt PA PTR valve Line strainer TX Concrete plinth a Heat pump Tempering valve Electric Tempered water pipework controller insulated Hot water pipework insulated Cold water pipework Chapter 6 System Types 69 CHAPTER 6 Figure 6 10 Split heat pump system installation diagram ylomadid JSJEM pop peyejnsur yJomedid Joyem 10H peyejnsul 1oMedid Jajem pe4eduJo onen Buueduie Jaure s our A PA YH ld A J8A uolsuedx J9Jem poo onen Huu 94nssaJld A 8A UJn 19J UON SAA UOI 8JOS VS XK El K KI Pd JosseJduuoo duund 1e9H Quoulne eso yum x29u2 19 0 1JUO09 Buiquinid 1 u Jayjem poo 911199 3 yup 96e 10 8 duund JeoH uuid ejesuoy Im yue oDe10js wo uieJq lt UIW ul gt id E A y A MOJ J9 eM pjoo S Y w k A jenno JaMOd eJeuo c AN lt P SoJn xij JEU 0 Jojem poJeduio yup a6e10 s 0 UJn 9J 1972M JOH EE
122. rter pipes from the tank to the taps In cold climates locating the tank internally or in a semi enclosed area may help prevent heat losses Figure 2 7 shows the possible positioning of the storage tank for a home where the main areas of hot water use are located on the same side of the house Figure 2 7 Location of storage tank relative to main areas of household hot water use single side Toilet Dining qp I I T Recommended location of qa Possible location of ground mounted hot water tank solar collectors Not all households have all the areas of hot water use on the same side and depending on the demand generated by the additional area the tank may need to be positioned slightly nearer to the additional areas as shown in Figure 2 8 20 Chapter 2 Design Principles Figure 2 8 Location of storage tank relative to main areas of household hot water use multiple sides qp aa I I Recommended location of Possible location of Main areas of hot water use li ground mounted hot water tank i solar collectors 2 5 2 Location of solar collectors Solar collectors should be located as close as practicable to the tank taking account of their orientation and inclination see Chapter 3 Solar collectors 2 5 3 Location of roof mounted tank Where the solar hot water system is entirely roof mounted as in a close coupled system the tank should be mounted as close as practicable to the
123. s will usually require additional safety precautions Although those requirements will vary from site to site installers may need to use a wider platform a higher guardrail scaffolding or a cherry picker as well as or instead of a fall arrest system Chapter 8 Occupational Health amp Safety 91 co en kd bm x xX bad o CE 853 bem x x ta 8 9 Brittle or fragile roofs Where portions of the roof are brittle or fragile an employer must ensure that the risk is controlled by either a permanent walkways b appropriately secured temporary walkways over the affected parts of the roof 8 10 Other relevant Australian standards for working at heights Installers should contact their state or territory government or local council for additional requirements 8 11 Falling objects When working on rooftops installers are sometimes at risk from falling objects Potential risks include a Collectors tanks and equipment may fall while being lifted to roof height or being installed at height b On tile roofs when tiles are slid aside so that the straps to support the tank can be attached to trusses rafters or trusses underneath there is a high risk that tiles will fall On tile roofs heavy plastic sheet or aluminium sheet can be laid under hot water storage tanks when they are roof mounted to ensure that if the tank fractures any tiles no debris will fall into the roof space Plastic or other she
124. sing work times to avoid the UV peak of the day b making use of natural or artificial shade C wearing appropriate protective clothing hats and sunglasses d using sunscreen Other weather hazards include heavy rain dew or wind as well as poor light in certain weather conditions Those conditions need to be assessed unsafe hazards avoided where possible or dealt with on site keeping in mind occupational health and safety regulations and best practice 8 16 Site assessment Sites should be assessed for a natural features and environment b under and above ground services e g gas phone electrical sewer water C site roof conditions and materials d buildings and other structures e suitable access 8 17 Maintenance and service The entire system including the following services should be shut down before any maintenance is performed a electricity or gas b generators c pumps d mains water supply e gravity water supply 94 Chapter 8 Occupational Health amp Safety F i w A a e e Gag Po x E pa 9 1 General Solar and heat pump hot water system installations should comply with all relevant standards and manufacturers requirements Installation requirements for solar water heater and heat pump systems include the following a AS NZS 3500 2003 Part 4 Heated Water Services Section 6 Installation of Solar Water Heaters b AS NZS 3000 Wiring Rules
125. sly to maintain hot water supply Table 2 1 shows the approximate daily hot water demand of various sized households Table 2 1 Approximate daily hot water demand and storage requirements for residential households No of Daily hot water Approximate size of occupants demand litres storage tank required litres 1 2 120 1602250 5 4 200 2509550 SEEGER 300F 400 Source Adapted from Sustainability Victoria Choosing Hot Water System Fact Sheet 2002 Where possible the future water needs of the family should be factored in as new members to the family or young children growing up can have an impact on hot water demand and the type of system that best suits these needs 2 4 2 Storage tank It is recommended that households have at least one and a half to two days of hot water in storage in the event of zero solar input for a day Table 2 1 has taken account of this storage need in the calculations of tank sizes for different size households 18 Chapter 2 Design Principles 2 4 5 Collectors Solar collector requirements will vary depending on whether flat plate or evacuated tube collectors are used The level of performance of collectors will depend on the manufacture Manufacturers recommendations should be followed 2 4 3 1 Flat plate collectors It is recommended that a one square metre area of collector space be used per occupant and for each major appliance using hot water from the solar hot water system e g a d
126. ss section Fipewoark Fr ur SSS s mam r N UV resistant flexible rubber maulding mi a o Qa M tal roof Flashing frame Insulation Where possible penetration should be done on the high part of the roof profile to avoid the possibility that water will pool around a penetration that is located in the valley of the profile Lead flashing should not be used on a roof that is collecting rainwater for drinking and it must be compatible with other roof cladding material 104 Chapter 9 Installation Considerations 9 2 4 Heat pump installation As is the case for any ground mounted tank a heat pump should be located on a level surface as close as practicable to the main areas of hot water use However the requirements for positioning and installing heat pump systems are different from the requirements for positioning and installing solar water heating systems Heat pump systems will be more efficient if placed in a warm location because it will take less time to heat the water to the set temperature In Australia the warmer locations are on the north side or west side of the house Heat pump systems need to be well ventilated so cold air can move away freely check the manufacturer s recommendations Heat pump systems can be noisy so they should be placed away from bedrooms and windows and any night time operation of the unit should be kept to a minimum if possible The manufacturer s specific
127. stem fitted with a tempering valve Figure 6 1 Thermosiphon system with a tempering valve fitted Hot Water Return Roof Mounted Hot Water Storage Tank PPP PP P bee Roof Mounted Solar Collectors I I Y Y Y Y i Tempering Valve Y Y Y ra Y TV gt gt gt 4 Tempered Water to House Fr lt al BM BM BM Cold Water Inlet 60 Chapter 6 System Types 6 2 Forced circulation systems split or pumped systems Split or pumped systems unlike the close coupled system comprise roof mounted collectors and a ground level storage tank Because the storage tank is on the ground a pump is required to circulate the water up to the collectors and back to the storage tank Water supplied to the storage tank from the main cold water inlet is pumped up to the bottom of the solar collectors by a pump built into the bottom of the tank or by an external pump The pump is operated by a controller which detects water temperature using sensors in both the solar collectors and the storage tank When the water in the storage tank is lower than that of the solar collectors the pump is switched on to circulate the hotter water to the storage tank and the cooler water up to the solar collectors for heating In split systems the collectors may be of the flat plate Figure 6 2 or evacuated tube type Figure 6 3 The water is then heated by the solar colle
128. sul ylomadid Jojem pjo2 peyejnsur x 1oMedid 191e 10H paje nsu 10Medid Jajem poeJeduue SALA 19JSUEJ Je OS onen Duueduie JeureJis our gt v onen H1d VK onen UOISUBOXO 19 eM pop onen Buw eunssaJg A 8A UJn 9J UON anjen uonejos de dois El Ej K KI H Ld JO ureaq 100 sBunooj pue Jejeau jo eseq yz ay wo Aeme abreyosip pinoys Hm onen UOISUBOXO 1942M pJO2 4 ulul900 O00c gt gt gt 19 U JOJeMA po Y i i e e e e el e V PDEEEEEEEEEEEEEIEIEJ E aK X lt lt lt e i cm E IS Joye paladusa Y Y y A ry L A Y gt M JOJ1uO2 dung Vu Ca Y V C Eu xs a sx J 1O12 OO 01 seur MO J ml i K K K K K K K ARK K J ll P cee P b P ce P VT P b b b U ee b P5 b b b Pb P ce em am au gt J0 99 109 eqn pejenoe 3 9 4iLdUH 62 Chapter 6 System Types 6 3 Gravity feed systems remote storage Gravity feed systems are low pressure systems that rely solely on thermosiphon flow principles to operate These systems have been used in homes not serviced by reticulated mains water Similar to split systems the storage tank is not located with the collectors The tank is located above the collectors in a remote location such as the ro
129. surrounding air before it flows to the compressor where it is pressurised When the refrigerant is pressurised it naturally heats up to approximately 60 C and is pumped through the condenser as a hot gas The condenser can be a coil of tube wrapped around the inner shell of the storage tank or coiled inside the tank itself It may also be a mantle type array of channels in contact with the inner shell of the tank As the water in the tank is at lower temperature than the refrigerant the heat is transferred from the condenser to the water This process cools the refrigerant which is then pumped through the expansion valve further reducing its temperature and pressure as it flows back into the evaporator Figure 6 8 wu RAS f c EK d By the time the refrigerant enters the evaporator its temperature is lower than the ambient outside air temperature and it is able to absorb the heat from the surrounding air through the evaporator where the process repeats Chapter 6 System Types 67 wu CE RES j x EL id The compressor can be mounted on top of the storage tank compact system Figure 6 9 or separately mounted beside the tank split system Figure 6 10 The heat pump must be connected to the continuous electric tariff and have unrestricted airflow The heat pump may run on a timer in areas where noise is an issue Figure 6 8 Heat pump system with external heat exchanger Accumulator Evaporator Co
130. t that results from the combination of iron steel and oxygen to form iron oxide DC power Direct current an electric current flowing in one direction only Diffuse radiation The component of incoming solar radiation which is scattered by clouds and other gases or particles in the atmosphere Direct radiation The component of solar radiation that comes direct from the sun as parallel rays EPDM The acronym for ethylene propylene diene monome a flexible rubbery plastic like material used for roof flashings EST Eastern standard time Efficiency of collector A measure of the fraction or percentage of energy in the heated fluid leaving a collector compared to the incoming incident solar radiation falling on the collector surface area Electrolysis The reaction between two dissimilar metals It is possible to predict which of the two will be eaten away by the other using the noble metals chart Evaporator A heat exchanger consisting of either a flat plate with tubes attached or a set of fins attached to a network of tubes In a refrigerator it is the plate inside the cabinet at the back that gets cold It absorbs heat from the food in the refrigerator An evaporator is part of all heat pump systems Expansion valve A valve which controls the rate of refrigerant flow through the evaporator in a heat pump system Forced circulation Freezing temperature of water Circulation that does
131. tal dark coloured plastics glass and solar collectors include a storing equipment in a shaded or covered location before and during installation b If necessary organising covers for solar collectors during roof installation where collectors are placed on roof scaffolding or platform while tiles are moved or the collectors security lines or installation points are checked Chapter 8 Occupational Health amp Safety 93 co en kd bm a xX bad o CE 853 bem x x ta Metal heat hazards can also include metal fittings in fall arrest systems buckles and D rings snaphooks on lanyards karabiners and other specific system fittings 8 14 2 Metal hazards Aside from general heat concerns see above solar water heating and heat pump installations also require installers to cut down metal lengths for the installation of tanks and collectors creating risks of cuts and injuries Measures to reduce those risks include using personal protective gear including covered boots gloves and protective eye wear 8 15 Hazards for working outdoors As for any site work installers must include hazards relating to working outdoors in their risk assessment The major risk factor is always working in the sun especially during the months September to April The most effective means of reducing sun exposure is a combination of protection methods The following controls are listed in order of effectiveness a reorgani
132. ted through the same plug and GPO as the pump system or through a separate GPO or hard wired connection All gas booster ignitors should be connected to continuous tariff electricity as they must be able to function at any time so that water can be raised to 60 C to prevent the development of Legionella 9 2 9 Heat pumps Heat pumps require a standard 10A connection Depending on the manufacturer s requirements this can be hardwired or connected through a GPO 9 2 10 Commissioning The commissioning process may vary from system to system and for this reason the manufacturer s commissioning process should be strictly adhered to The system must be full of water and or heat transfer glycol fluids before it is turned on 106 Chapter 9 Installation Considerations 9 5 Installation checklist Environment ODO 00 oy a kai fece c E aoe ta Water quality is suitable for contact with components Components and materials will not react with other materials when in contact with them e g galvanic reaction All components are suitable for the environmental and climatic conditions There are no known impacts on the environment resulting from this installation Solar collectors 0000 Collector is pitched and oriented to achieve good solar gain Collector is positioned to avoid shading throughout the year Collectors connected in parallel are plumbed for balanced flow conditions if applicable Collectors are fitt
133. tempering valve should be copper or copper alloy c Pipework from the tempering valve into the building can be of any approved pipework material d As per AS NZS 3500 4 plastic pipework should not be used I in between the solar collectors or other uncontrolled heat sources and the storage tank ii for the drain line from the pressure temperature relief valve iii to support isolation valves non return valves and equipment used to connect to water heaters 5 2 2 Fittings Compression fittings and valves should be constructed of brass or copper Plastic fittings should not be used 5 5 Pipework size 5 5 1 Diameter The following guidelines for pipework diameters should be followed a Pipe diameter between the storage tank and the solar collectors needs to be sized appropriately to AS NZS 3500 taking into consideration i flow ll pressure iii pipework length 52 Chapter 5 Pipework amp Fittings b Flow and return lines should be a minimum of 15mm copper for mains pressure and pumped systems The velocity and pressure of water flow between the storage tank and collectors can vary greatly in solar hot water systems Refer to the manufacturer s recommendations c Pipework in a system driven by thermosiphon flow should be 25mm 5 5 2 Length 5 5 2 1 General Pipe length should be kept as short as possible to minimise heat loss from water 5 5 2 2 Drain line from PTR valve Drain lines from the PTR valve should
134. thwest 315 for all other states 5 5 2 True north and magnetic declination 5 5 2 1 Finding north A compass will point to magnetic north which has a variation from true north This is called magnetic declination While the difference may have little effect it is recommended that magnetic declination be compensated for to achieve optimal performance from the collectors Figure 3 5 Magnetic declination Perth and Hobart Magnetic North N True North True North Perth 1 49 W bs ON s Hobart 214 79 E W E S Table 3 1 Magnetic declination angles of major cities City Declination angle east west of magnetic north Adelaide 8 2 East Alice Springs 5 1 East Brisbane 11 East Cairns 8 5 East Canberra 125 East Darwin 5 4 East Hobart 14 7 East Melbourne 11 5 East Perth 1 4 West Sydney 12 5 East Source Geoscience Australia www ga gov au Chapter 3 Solar Collectors 51 Figure 3 6 Magnetic declination topographical map a T Wi F AN E q FX L po F T 15 F L Y re amp uw fu a El E A 1 i 4 LATITUDE or tro 1207 307 140 150 Teor t70 160 Magnetic declination LONGITUDE Commonwealth of Australia Geoscience Australia 2009 3 3 2 2 Adjusting for true north The magnetic declination angle for the location should be added to the compass reading for north to obtain the true north heading 3 3 3 Inclination tilt
135. to the bottom of the tank through a spreader pipe that slows the water velocity and spreads it along the bottom of the tank Water returning from the solar collector should be fed back into the tank at a higher position than the cold water outlet Figure 4 2 shows a close coupled thermosiphon system with stratification or temperature induced water circulation Figure 4 2 Close coupled thermosiphon system showing stratification F ec Ed CD lt p The hot water outlet should be drawn from the top of the tank to ensure that a the water at the highest temperature is drawn b the likelihood of mixing water is reduced Figures 4 5 and 4 4 show typical un boosted vertical and horizontal storage tanks Chapter 4 Storage Tanks 47 Figure 4 5 Typical vertical storage tank Anode cap High density tank insulation Hot water return from solar collectors Hot water outlet to tempering valve BN Dip tube standard solar Dip tube standard solar Outer casing Cylinder Anode Vitreous enamel tanks Stratification of water Dip tube retrofit Cold water flow to solar collectors Cold water Inlet SL P di E er e u e XL pe taf Figure 4 4 Typical horizontal storage tank Inner Cylinder Insulation Anode Outer casing Hot water outlet in Hot water from Cold water Inlet solar collectors Cold water to collectors Stratification of wate
136. tors outlet to tap or tempering valve Outer casing r T w w w w w w w Cylinder Heat exchanger coil Cold water Inlet Cold water glycol flow to solar collectors IN ELLA LL k w w w w w w w w w Stratification of water er e didi u e XL pe taf 50 Chapter 4 Storage Tanks Chapter 5 A a 5 1 General All pipework connectors and fixtures used in a solar or heat pump hot water system must be copper or metal to avoid the potential melting and deforming of polymer pipes If the water pipe system contains conductive e g metal water pipe that is accessible within the building and is continuously conductive from inside the building to the point of contact within the ground this pipe must be equipotentially bonded to the earthing system of the electrical installation Where copper or metal pipework in any part of a system is replaced with polymer or equivalent non conductive pipework the equipotential bonding of the system components must be re established reference AS NZS 3000 2007 Pipework and fittings used in solar hot water installations must be installed in accordance with manufacturers specifications where those specifications are not in direct conflict with AS NZS 3500 4 5 2 Materials 5 2 1 Pipework The following guidelines for pipe materials should be followed a Flow and return lines should be copper or copper alloy b Pipework from the storage tank to the
137. ueduis JeureJjs our SAMBA Y ld A 8A uolsuedx J9 eM PJOD aA ea Huu eansseJg SAJCA UJh19J UON SAA UOI EJOS X E K lt Pd uw w gt ueg gt KIS u1u00 00c i 19 21220100 Aiuouine e20 yum x29u2 l Duiquunjd Jour Jajem pJo2 e im i i ll ll ll A A A ll A A 5 A A A I ma aa m lin a lt a a a a gt gt gt im E i n Y A Y A i lt uluJ WY gt AL i 9 UI JOYEM pJO2 P P P e P b A eui ued f n SALA YH ld lt A SOINIXI BUO U O Jayem paleduwa 19 eM pajesy Je OS 9AI92981 0 9 qejins Jayesy Jayem Joy Duisix3 au urejp Y ld el gt e M gt gt eee mb ER 1949e1q uoddng E UILU LULUQOS Y yue wo A ATT MoO M PIOD suy u0Issalduo 2 10198uuoo pexue g sDuluse J JOOy que 0 uJn 9J Joyem 10H sss yue Beuols peijunouu punoJ6 0 UJn19J J9 eM JOH 4 uoiun Bm OM ulu LULUQOG Y SAMBA H ld lt UW Wwupos gt lt uu wuoos gt 9 4iLdUH 72 Chapter 6 System Types Figure 6 12 Pre heater split system retrofit to existing storage tank installation diagram paje nsul uJn19J MO JeJOS xXjowedid Jajem pop paye nsul ylomedid 19JEM 10H paje nsul ylomedid Jayem paledua paunba y 3A A UONDAJOIA 1501
138. ulated by determining the amount of electricity the system displaces over a determined period called a deeming period Each REC is equivalent to IMWh of renewable electricity generated or deemed to have been generated The number of RECs is also dependent on where the system is installed The amount of sun a system receives each day varies from location to location Each postcode is allocated a zone rating based on the solar radiation levels in Australia and the water temperature in the area If the system has a higher zone rating it has the potential to displace a greater amount of electricity and is entitled to more RECs Table 12 1 shows how Australian postcodes are currently zoned for renewable energy certificates 116 Chapter 12 Government Incentives Postcode range Postcode range Table 12 1 Renewable energy certificate zones for all Australian postcodes Postcode range From To Zone From To Zone From To Zone 200 299 750 5898 4 529 526 800 862 5900 5900 3 5262 5265 4 870 872 2 5907 3996 4 5264 5270 3 880 909 1 4000 4419 3 5271 5291 4 1001 2914 S 4420 4420 1 5301 6256 5 3000 3381 4 4421 4428 3 6258 6262 4 3384 3384 5 4454 4454 6271 6318 3 505 3387 4 4455 4468 3 6320 6338 4 3388 S596 4470 4475 2 6341 6341 3 599 3413 4 4477 4477 6343 6348 4 3414 3424 5 4478 4482 2 6550 6353 5427 545 4 4486 4488 3 6355 6356 4 3453 3453 3 4489 4493 2 6357 6395 3
139. urn from solar collectors Cold water Inlet Glycol flow to solar collectors Solar collectors gt gt gt p gt P P P P P b 58 Chapter 3 Solar Collectors 3 3 7 Over temperature protection 3 3 7 1 Solar collectors Figure 3 12 Typical flat plate collector Header connections to valves collector or hot water return Riser tubes Header connection to collector valve or cold water flow Transparent hardened glass cover Header tube Absorber plate Collector box Insulation Termination plug or connection to collector valve or cold water flow The water inside solar collectors can reach boiling point 100 C The collectors themselves cannot stop heating water and regardless of the demand for hot water the collectors will continue to feed the storage tank with boiling water To reduce the risk of system failure it is important that the water in the storage tank does not exceed 70 C This can be achieved by a a solar control valve on the cold water flow line to the collectors that detects when the water in the storage tank reaches 7O C and closes to prevent hot water flowing to the collectors As hot water is drawn off and cold water enters the tank and reduces the water temperature the valve will open to allow water to flow to the collectors b the circulating pump controller in split systems which turns the pump off when the temperature in the storage tank
140. ush with the rafters 9 2 2 2 In ceiling tank gravity feed A suitable location in the ceiling cavity must be identified and a section of roof removed to enable the tank to be placed into position A hardwood reinforced stand will need to be constructed to support the tank in the ceiling This stand must be high enough for the tank to sit at least 500mm above the top of the collectors As ceiling joists may not carry the weight of a full tank the stand must span at least two supporting walls as The surface area of the base of the stand must be larger than the safe tray that sits under the tank 9 2 2 5 Ground mounted tanks Ground mounted tanks should be positioned on a level surface as close as practicable to the main areas of hot water use Where the ideal position is in a garden bed or grassed area the ground should be compacted and a concrete plinth laid beneath the tank Adequate space must be available for installers to access pipe connections PTR valve and anode In gas storage or gas instantaneous boosted systems clearances from windows should be in accordance with AS 5601 9 2 5 Roof flashings Roof penetrations for pipework electrical conduits or support frames should be sealed with roof flashings to prevent water leaking into the roof cavity These flashings are usually made of EPDM or silicon rubber with an aluminium frame that can be moulded to the shape of the roof Figure 9 9 Figure 9 9 Roof penetration cro
141. y criteria and exemptions The program for existing homes will be extended during 2012 Stage 2 to cover all detached houses terraced houses and townhouses and hostels A working hot water system will not need to be replaced but when a system needs to be replaced it will be with a low emission alternative 13 2 Phase out of electric water heaters The phase out will be implemented in two stages 15 2 1 Stage 1 Commencing during 2010 the phase out of greenhouse intensive electric water heaters will be implemented on a state by state basis for Class 1 buildings new and existing detached houses terraced houses town houses or hostels where such requirements do not currently exist Programs for new homes are already in place in South Australia Queensland Victoria Western Australia and New South Wales Programs are already in place for existing homes in South Australia and Queensland State and territory governments have details on local programs For more information about these programs go to the following websites Queensland new and existing homes www dip qld gov au sustainable housing electric hot water system replacement html South Australia new and existing homes www energy sa gov au a 30372 New South Wales new homes only www basix nsw gov au Victoria new and existing homes www pic vic gov au www html 249 5 star standard asp www new dpi vic au energy energy policy energyefficiency waterheat
142. y is required where the water storage tank is located inside buildings so that water does not cause damage within the building The safe tray must be drained to the outside of the building and the drain pipe must be visible so that if it does have water escaping it will be noticed Scale The name given to the build up of mineral deposits within a water heater that is using hard water It occurs on electric elements the walls of storage tanks and solar collectors It is usually calcium carbonate limestone and can be dissolved with acid such as hydrochloric acid Solar fraction The proportion of hot water energy demand at the outlet of the water heater that is provided by the solar collectors compared to the supplementary or boosting energy that is required to keep the water at a set temperature typically 60 C Solar radiation see also irradiance or irradiation The spectrum of radiant energy emitted from the outer layers of the sun It consists of a range of wavelengths of electromagnetic radiation from ultraviolet to visible light and infrared radiation 154 Chapter 14 Glossary Split systems See pump circulated systems Stainless steels Stainless steel comes in various grades some more resistant to corrosion than others Grade 316 is commonly used when a relatively high standard of corrosion resistance is required Stratification The formation of layers of water of different temperatures w
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