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SDFI - Sterling HVAC

1. See Below PS 12 Clogged Filter Switch Adjust to field condition PS 13 Building Pressure Switch Adjust to field condition FL 02 High Temperature Limit Manual 185 F Note Set high gas pressure setting 125 above burner firing rate SECTION VI UNIT SHUTDOWN A Extended Shutdown 1 Set the Heat On Off switch to the Off position for 30 seconds then turn the Fan On Off switch to Off position 2 Close all manual gas valves 3 Open the main electrical disconnect switch B Emergency Shutdown ONLY 1 Open the main electrical disconnect switch 2 Close the main manual gas valve SECTION VII TROUBLE SHOOTING HONEYWELL RM7895A B C D EC7895A C RM7896A B C D 7800 SERIES RELAY MODULES PRINCIPAL TECHNICAL FEATURES The RM7895 RM7896 provides all customary flame safeguard functions as well as significant advance ments in safety annunciation and system diagnostics Safety Shutdown Lockout Occurs if 1 INITIATE PERIOD a Purge card is not installed or removed b Purge card is bad c Configuration jumpers have been changed after 200 hours d AC line power errors occurred see Operation e Four minute INITIATE period has been exceeded 2 STANDBY PERIOD a Airflow lockout feature is enabled and the airflow switch does not close after ten seconds or within the specified purge card timing b Flame signal is detected after 30 seconds c Ignition pilot
2. L 7 1 4 NEW FLAME ROD 71 0213 00 STEP 1 BEND ROD AT 45 ANGLE 3 FLAME ROD FROM FITTING DO NOT DAMAGE PORCELAIN 3 SPARK IGNITOR OPENING 71 0213 12 PILOT TUBING lt WHEN REQUIRED MAIN GAS MANIFOLD lt STEP 2 CUT ROD TO A LENGTH OF 2 AFTER THE 45 BEND 20 TROUBLESHOOTING GUIDE Series 14 Discharge Temperature Control Reproduced with permission from Maxitrol Company Symptom Possible Cause Field Test Remedy A No Gas Flow 1 Modulating valve improperly installed or see Symptom L Arrow on side of valve should point in direction of gas flow 1 Install properly B Continuous Low Fire Electronics Problem Short circuit or no voltage to the amplifier Open circuit in TD114 Remote Temperature Selector circuit or wiring Short circuit in 75114 Discharge Air Sensor circuit or wiring Faulty amplifier Check for 24V AC at amplifier terminals 7 amp 8 Inspect for loose or broken wires between amplifier terminals 1 amp 2 and TD114 terminals 1 amp 3 Connect test resistor as described in Preliminary Circuit Analysis in Section IX Follow procedures outlined Check items B1 3 Prove the power source Tighten connections or replace wiring If modulating voltages are obtained check TS114 circuit for shorts Replac
3. negative pressure check equipment for clogged filters and other inlet air restrictions For other solutions consult factory Control circuits external to Series 44 can cause burner malfunction Always check manual valve to be certain gas is on and check limit controls for normal operation Series 44 Room Temperature Control continued TROUBLESHOOTING GUIDE Reproduced with permission from Maxitrol Company Symptom Possible Cause Field Test Remedy E Continuous 1 Faulty amplifier 1 Follow procedures 1 If amplifier is proven at temperature calibra tions in Preliminary Circuit Analysis in Section IX Minimum outlined in Preliminary fault install replacement Discharge Air Circuit Analysis in Section amplifier Temperature IX 2 Short in T244 or Remove wires connected If reading is incorrect TS244 TD244 circuit to amplifier terminals 4 amp 5 replace the T244 TS244 Set T244 or TD244 to TD244 or repair wiring maximum setting Measure resistance across wires Meter should read 6000 ohms 1000 T244 If TS244 TD244 are used meter should read 4500 ohms 1000 TS244 and 2100 ohms 150 TD244 3 Incorrect space Follow procedures outline If proper action is obtained temperature calibra in Preliminary Circuit first check item 12 tion Analysis in Section IX Recalibrate if necessary F Incorrect 1 Improper TS144 Compare sensed Move TS144 to loc
4. 50 60 HZ EC7895 220 240 J SEE FLAME DETECTOR SPECIFICATIONS FOR CORRECT WIRING 50 60 HZ POWER SUPPLY PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED A DO NOT CONNECT ANY WIRES TO UNUSED TERMINALS RMz8966 D ONLY 7895 A 220 TO 240 VAC TO 120 VAC 10 VA MINIMUM STEPDOWN AIRFLOW SWITCH CHECK FEATURE IS FOR THE RM7895D RM7896D A RM7895C 1020 RM7896C1036 PFEP 10 SECONDS ONLY TRANSFORMER NOT PROVIDED MUST BE USED TO DRIVE THE SHUTTER AM7896C1036 DURING FIRST 8 SECONDS OF PFEP WHEN A FLAME SIGNAL IS DETECTED TERMINAL 10 IS DE ENERGIZED IF FLAME SIGNAL IS LOST TERMINAL 10 WILL RE ENERGIZE sae M15124GR SECTION VII TROUBLE SHOOTING continued United Technologies Electronics Controls Operation of the Series 1016 400 Direct Spark Ignition Control On a call for heat a five second pre purge is initiated Upon completion of the pre purge the gas valve and 60 Hz spark are energized When flame is detected the control enters the steady state heating condition Steady state heating will continue until the call for heat is satisfied If ignition is not achieved within 15 seconds the control shuts off the gas and locks out If the trial for ignition has been accomplished without ignition the control shuts off all outputs and enters lockout Reset is accomplished by cycling the power off for a minimum of 5 seconds If flame is lost once it has bee
5. System without Pilot continued TROUBLESHOOTING GUIDE Symptom Cause Remedy C continued 10 Defective gas valve or actuator Defective spark rod or out of position see spark rod diagram P 001004 Check power to gas valves If gas pressure matches unit rating plate and valve does not open replace gas valve or actuator Make sure spark rod is producing a sufficient spark to light off burner make sure porcelain is not cracked Check wiring or replace if necessary 11 Flame rod not sensing flame 11 Make sure flame rod is in flame see spark rod diagram Make sure porcelain is not P 001003 cracked Check wiring or replace if necessary 12 Defective regulator 12 Clean or replace regulator 13 Blocked vent lines or vent 13 Check vent lines or replace limiters limiters 14 Low fire set too low or too high 14 Adjust setting on modulating valve or gas valve D Burner will not respond 1 For Maxitrol system 1 See following troubleshooting to temperature guide for Maxitrol series 14 amp 44 2 For Honeywell system 2 See following troubleshooting guide for Honeywell 19 TROUBLESHOOTING GUIDE P 001004 ft 0625 Se RT A SN ea IGNITOR ASSY DETAIL FLAME ROD 71 0213 00 SPARK IGNITOR 65 0910 30 e700 00 O O PILOT TUBING WHEN REQUIRED MAIN GAS MANIFOLD PILOTLESS SYSTEM P 001003
6. 2 turn power ON 2 Turn Test Potentiometer to minimum resistance Voltage should be 0 volts 3 Turn Test Potentiometer slowly to maximum resistance The DC voltage should gradually increase to at least 18 volts If proper voltages are observed in both Section 1 and 2 the amplifier is satisfactory If proper voltages are not observed continue testing to identify the difficulty Faults may be identified with the amplifier the 24V power supply or the circuit connected to terminals 6 and 7 Section 3 1 Observe burner flames and or burner pressure as Test Potentiometer is turned through full range NOTE From 0 5 volts heater should be at bypass or low 5 15 volts heater should respond with various input rates beyond 15 volts heater is at maximum input If proper operation is observed continue procedure to check operation of sensing and selecting components If proper operation is not observed see Trouble shooting Guide to test M or MR valves and con necting wiring si Section 4 Figure 1 1 With proper voltages observed thus far and modu lator responding correctly wire the system see Figure 1 except have TS144 connected in place MT1 12 TS144 of jumper Set A1044 MIN temperature selector at least 10 F above outdoor temperature Set A1044 MAX temperature selector at mid range Heater is ll now under control by TS144 Discharge Air Monitor 999 2 Turn Test Potentiometer to maximum resis
7. A and turn regulator pressure 2 Adjust the pressure regulator to obtain the desired adjusting screw to obtain desired manifold pres manifold pressure 7 w c maximum sure Clockwise rotation increases pressure 3 Reconnect the wires to amplifier terminal 4 3 Reconnect the wires to amplifier terminal 4 Series 14 or 2 and 4 Series 44 Series 14 or 2 and 4 Series 44 Low Fire or Bypass Adjustments NOTE If low bypass is on maximum the desired 1 Disconnect wire from amplifier terminal 8 This high fire outlet pressure may not be achieved causes the valve to call for continuous low fire 2 Remove cap A and turn adjusting screw B to Low Fire or Bypass Adjustments desired low fire adjustment Clockwise rotation 1 Disconnect wire from amplifier terminal 48 This reduces minimum flow rate causes valve to call for continuous low fire 3 Replace cap A and reconnect wire to amplifier 2 Remove cap B and loosen lock screw C Turn terminal 8 D to desired low fire adjustment Clockwise rotation reduces minimum flow rate 3 Tighten screw C replace cap B and reconnect wire to amplifier to terminal 8 EA PRELIMINARY CIRCUIT ANALYSIS SYSTEM 14 For ease in troubleshooting it is advisable to wire the system as follows this differs from the normal connec tion The Discharge Air Sensor is disconnected and replaced with a 10 000 ohm 1 2 watt test resistor terminals 3
8. Inspect for shorts at or between Amplifier terminals 1 amp 2 or TD114 terminals 1 amp 3 Check TS114 TS1007 for open internal circuit Connect test resistor as described in Preliminary Circuit Analysis Follow procedure outlined Inspect Correct wiring if shorts exist If modulating voltages are obtained check TS114 TS1007 for open circuits Replace TS114 TS1007 Correct the wiring ok Series 14 Discharge Temperature Control continued TROUBLESHOOTING GUIDE Reproduced with permission from Maxitrol Company Symptom Possible Cause Field Test Remedy F Continuous High Fire Electronics OK 1 Foreign object holding valve open 2 Plunger jammed Remove bottom plate and inspect valve and seat Inspect Plunger should be smooth and clean and operate freely in solenoid sleeve 1 Clean seat Clean valve or replace if necessary 2 Clean or if necessary replace plunger G Incorrect Maximum Fire 1 Inlet pressure too low 2 Incorrect outlet pressure adjustment of Pressure Regulator Read pressure at inlet to modulating valve using a manometer with unit operating at full fire Pressure should be equal to the sum of outlet pressure setting plus pressure drop of the valve Read manifold pressure using manometer and compare with the pressure stated on the specification plate 1 Increase inlet pressure if possible See
9. S DFIM 3 Sz 9 Hm EMLINU HVAC PRODUCTS INSTALLATION OPERATION AND MAINTENANCE MANUAL FOR SDFW amp SDFI DIRECT GAS FIRED HEATERS ATTENTION READ THIS MANUAL AND ALL LABELS ATTACHED TO THE UNIT CAREFULLY BEFORE ATTEMPTING TO INSTALL OPERATE OR SERVICE THESE UNITS CHECK UNIT DATA PLATE FOR TYPE OF GAS AND ELECTRICAL SPECIFICATIONS AND MAKE CERTAIN THAT THESE AGREE WITH THOSE AT POINT OF INSTALLATION RECORD THE UNIT MODEL AND SERIAL No s IN THE SPACE PROVIDED RETAIN FOR FUTURE REFERENCE FOR YOUR SAFETY The use and storage of gasoline or other flammable vapors and liquids in open containers in the vicinity of this appliance is hazardous POUR VOTRE SECURITE L utilisation et l entreposage d essence ou d autres liquides ou produits mettant des vapeurs inflammables dans des r cipients ouverts proximit de cet appareil est dangereux FOR YOUR SAFETY POUR VOTRE S CURIT If you smell gas Si vous sentez une odeur de gaz 1 Open Windows 1 Ouvrez les fen tres 2 Don t touch electrical switches 2 Ne pas actionner d interrupteur 3 Extinguish any open flame 3 Eteindre toute flamme ouverte 4 Immediately call your gas supplier 4 Appelez imm diatement votre iru fournisseur de gaz WARNING Improper installation adjustment alteration service or maintenance can cause property damage injury or death Read the installation operating and maintenan
10. Season or Yearly a Complete the monthly and quarterly maintenance schedule b Inspect all fan wheels and housings Clean if necessary c Check that all fan wheels and sheaves are securely set on the shaft d Inspect all bearings and alignment Adjust if necessary e Inspect all V belts Replace if necessary f Inspect all electrical components connections and terminals Clean and tighten where necessary g Test ignition spark Adjust gap if necessary h Clean ignition electrodes and check for cracks i Test flame safeguard relay and replace components if necessary j Inspect all regulators relief valves motorized valves solenoid valves vent valves manual shut off valves and safety shut off valves Check their operation and clean as necessary Ensure all vents to the atmosphere are clean and free from obstruction Inspect and clean all drip legs in the fuel line m Lubricate fan motor as directed by motor manufac turer Inspect fan motor wiring for loose connections Lightly oil all door latches Check that cabinet is weathertight replace door gaskets and recaulk as necessary NOTE Keep screened air intakes clear of obstruc tions at all times B Lubrication Instructions Item Manufacturer Bearing Type All 3 phase US Baldor Single row ball fan motors or equal bearings 1 HP to 100 HP ODP TEFC Recommendation See following note All 1 phase Century G E B
11. Set inlet ductstat if applicable above outside air temperature Connect a DC microammeter between the SENSE terminal and the flame rod sensing wire Turn Fan and Heat OFF ON switches to ON position Open inlet manual gas shut off valve slowly Reset high and if applicable low gas pressure switches Check main gas line for leaks using soap solution Unit will run for 5 seconds before ignition trial NOTE 3 OR 4 TRIALS MAY BE NEEDED TO PURGE AIR FROM GAS LINE United Technologies Electronic Controls Spark Ignitor Watch microammeter carefully The reading should be at least 5 0 microamps If the reading is too low slowly turn the low fire adjustment on the modulating valve in or out until satisfactory readings are obtained When adjusting low fire there should be a continuous flame along the entire burner length without any blowout spots Refer to Maxitrol Valve Adjustment instructions in Section IX for setting high and low fire gas pressure settings When the flame is adjusted shut the unit off by turning the Fan and Heat switches to OFF Setting Main Flame Install manometer at test port on the last tee of the burner manifold or modulating valve Slowly open all manual gas shut off valves Restart unit After main gas valves open and burner lights check gas lines for leaks Adjust high gas pressure reading from manometer to match firing rate shown on unit nameplate Adjust the high fire setting according to
12. Symptom Cause Remedy A If blower does not Low or no voltage Check power source operate 2 Fuse s blown 2 Check and replace 3 Customer interlock not closed or 3 Close or connect customer connected interlock 4 Fan Off On switch in Off position 4 Switch to On position 5 Time clock night setback 5 Check time clock night setback thermostat or field installed thermostat and field installed controls open controls for proper settings 6 Freeze protection tripped 6 Reset freeze stat by interrupting power Check for proper setting and burner operation 7 Damper motor not operating or 7 Check for power at damper motor its end switch not making and that end switch has been wired correctly to the N O normally open contact Check that the linkage is clear and not binding 8 Overload Protection on motor 8 Push reset button on starter and starter tripped check amps 9 Belts loose or broken 9 Turn power off and check belts 10 Bearings seized 10 Check and replace 11 Motor may be burned or 11 Turn power off and check motor incorrectly wired and wiring 12 Motor overheating 12 Check burner firing rate B Ifthere is no voltage at 1 Heat Off On switch in Off position 1 Switch to On position flame safeguard relay 2 Auxiliary switch on starter not 2 Check auxiliary circuit wiring and input terminal closed contact 3 Air flow switches open 3 Adjust the air fl
13. accor dance with regulations of the National Board of Fire Underwriters National Electrical Code and local governing bodies The following recommendations are not intended to supplant any requirements of federal state or local codes having jurisdiction Authorities having jurisdiction should be consulted before installa tions are made Local codes may require additional safety controls and or interlocks All installations in airplane hangers must be in accor dance with current ANSI NFPA No 409 All installa tions in public garages must be in accordance with current NFPA No 88A and NFPA No 88B CAUTION Do not install heating system in corrosive or flammable atmospheres Premature failure of or severe damage to the unit will result CAUTION Heating system must not be installed in locations where air for combustion would contain chlorinated halogenated or acidic vapors If located in such an environment premature failure of the unit will occur A Handling the Equipment The Direct Gas Fired unit has been designed for rigging and handling through the use of special lifting lugs installed on the sides of each unit As explained previously the basic unit is designed for shipping in one piece where shipping limitations allow Some optional accessories may require field mounting When unloading and setting the unit use the lifting lugs provided or move the equipment on rollers Hooks jacks or chains must not be used around
14. fan housing must be removed to expose the grease plugs 2 Pillow Block Bearings Pillow block bearings are used on supply blower s Bearings have been prelubricated with a number 2 lithium base grease Relubrication should be done with a similar grease using a low pressure grease gun Wipe all grease fittings clean before adding grease Grease should be added slowly in small amounts at frequent intervals while the shaft is being manually rotated A slight showing of grease at the seals with accompa nying normal bearing temperature indicates proper lubrication Normal temperature can range from cool to hot to the touch depending on size speed and surrounding conditions Excessive bearing tempera ture indicates faulty lubrication An insufficient amount of grease is suggested by a bearing showing no grease at the seals and a higher than normal tem perature and noise level Excessive leakage of grease at the seals and a high operating temperature suggest too much grease Frequency of Lubrication Frequency of lubrication depends upon operating conditions The bearing operating temperature is the best index for determining a relubrication schedule The following chart gives the frequency of relubrication based upon continuous operation for various operating temperatures and can be used as a satisfactory guide for determining when all ball and roller bearings should be relubricated Speed Temperature Cleanliness Inter
15. instructions has been prepared in order for you to become well acquainted with those details and in doing so you will be able to give your Direct Gas Fired System the care and attention which any piece of equipment needs and deserves Table of Contents Section Forward and Table of Contents 2 Section Il General Information 2 Section lll 3 Section IV 5 Section V Unit Start Up 6 Section VI Unit Shut 2 222 8 Section VII Troubleshooting Guide 8 Section VIII Maintenance Schedule and Lubrication Requirements 23 Section IX Maxitrol Valve Adjustments and Preliminary Circuit Analysis 27 Section X Replacement 29 Section 31 SECTION Il GENERAL INFORMATION A Purpose The purpose of this manual is to present a guide for proper installation maintenance and operation of the Direct Gas Fired System and supplement but not to replace the services of qualified field service person nel to supervise the initial start up and adjustment of the unit Persons without previous experience with large commercial and industrial heating
16. the Maxitrol Valve Adjustment instructions in Section IX The high fire setting must not exceed the pressure stated on the rating plate Main flame is now set Recheck the microamp signal on the ignition control throughout the full burner input range Re check low fire setting Cycle unit 2 or 3 times to insure good ignition Safety Controls Check All A Flame Safeguard piloted systems only Close last manual gas valve before main burner Operate unit in Heat mode After pilot flame has been estab lished close manual pilot gas valve The flame safe guard must trip out within 15 seconds B Ignition Control pilotless system only Operate unit in Heat mode After flame has been established close last manual gas valve before main burner The ignition control must trip out within 15 seconds Reset the ignition control by turning the HEAT switch to the OFF position C Gas Pressure Switches The low pressure switch will trip out and must be reset before resuming opera tion when the inlet gas valve is turned off during operation The high pressure switch may be checked out by reducing the setting of its trip point to unit operating pressure It should then trip out and shut off the burner Return the adjustment to its original setting and reset to resume operation When checking operation of gas pressure switches on systems without pilot the heat switch will have to be turned off for approximately five seconds to res
17. the casing main control panel or exterior mounted controls During transit unloading and setting of the unit bolts and nuts may have become loosened particularly in the pillow block ball bearing assemblies in the fan section It is recommended that all nuts and set screws be tightened Turn fan shaft by hand to make certain that blower does not rub against blower housing and that bearing set screws are tight If units are not set immediately cover all openings that might be exposed to the weather Open the cover on the electrical control box located on the unit Inspect all wire terminals and wiring termina tions to ensure that all connections are tight If units are not set immediately cover all openings that might be exposed to the weather Rotate fans monthly B Locating the Unit Prior to locating the unit authorities having jurisdiction should be consulted before installations are made Approval permits should be checked against the unit received If in doubt regarding the application of this appliance consult the factory Locate the unit exactly level Special attention should be given to the duct electrical and fuel connection points Install duct work with adequate flexible connec tions to isolate vibration from the duct work All duct work should have taped or caulked seams Duct work should be properly sized so as not to inhibit airflow This information should be cross checked with the position of support
18. values are not observed replace modulator head or repair wiring Clean or replace plunger if necessary Replace diaphragm if ruptured C Continuous Low Fire Electronics Problem 1 No voltage to the amplifier 2 Short in modulator coil circuit 3 Short T8144 circuit 4 Faulty amplifier Check for 24V AC at amplifier terminals 8 amp 9 Measure resistance per item B1 Remove wires connected to amplifier terminals 1 2 amp 3 Measure resistance across wires 1 amp 3 then 2 amp 3 Meter should read greater than 2500 ohms Follow procedures outlined in Preliminary Circuit Analysis in Section IX Provide 24V AC to amplifier Refer to item K1 If proper resistance values are not observed replace the modulator head or repair wiring If readings are incorrect replace the TS144 or repair wiring If power source and modulator coil check out items 5 amp 6 but proper modulating voltages cannot be obtained then amplifier may be assumed at fault Install replacement amplifier D Incorrect Low Fire 1 Incorrect by pass metering valve adjustment 2 Excessive negative burner pressure See Valve Adjustments Section IX Close main gas supply and measure manifold pressure with blower operating Should be less than 1 5 w c negative pressure Adjust to proper low fire If greater than 1 5
19. valve adjustments in Section IX H Erratic or Pulsating Flame 1 Hunting 2 Erratic air patterns or improper TS114 location 3 Wiring is run next to high voltage switching circuits causing induced voltages 4 Faulty Amplifier or erratic voltage supply Adjust sensitivity control counter clockwise Connect test resistor as described in Preliminary Circuit Analysis Turn TD114 selector dial so heater goes through its entire modulating range Temporarily wire each TD114 TS114 and MR212 externally and observe heater equipment operation With test resistor con nected per Item 18 and TD114 locally connected per Item 19 turn TD114 selector dial through entire modulating range Observe D C voltage across modulator terminals 1 If flame stabilizes adjust sensitivity control to maintain an even flame 2 f the flame is steady throughout the entire modulating range the TS114 must be moved 3 If smooth operation results isolate effected wiring from source of induced voltage 4 If erratic or unstable D C voltages are obtained throughout the modulating range the amplifier may be assumed faulty Replace If erratic oper ation is noted only over a small range of 2 or 3 volts the voltage sources may contain surges Consult factory for other solutions 22 Series 14 Discharge Temperature Control continued TROUBLESHOOTING GUIDE Reproduced with permis
20. valve intermittent pilot valve terminal is energized d Main valve terminal is energized e Delayed 2nd stage main valve terminal is energized RM7895C D EC7895C RM7896C D f Internal system fault occurred g Purge card is removed h Purge card is bad 3 PREPURGE PERIOD a Airflow lockout feature is enabled and the airflow Switch opens b Ignition pilot valve terminal is not energized c No flame present at end of PFEP d Main valve terminal is energized e Delayed main valve terminal is energized RM7895C D f Internal system fault occurred g Purge card is removed h Purge card is bad 4 PILOT FLAME ESTABLISHING PERIOD PFEP a Airflow lockout feature is enabled and the airflow switch does not close after ten seconds or within the specified purge card timing b Flame signal is detected after 30 seconds c Ignition pilot valve intermittent pilot valve terminal is energized d Main valve terminal is energized e Delayed second stage main valve terminal is energized RM7895C D EC7895C RM7896C D f Internal system fault occurred g Purge card is removed h Purge card is bad 5 MAIN FLAME ESTABLISHING PERIOD MFEP RM7895C D EC7895C RM7896C D a Airflow lockout feature is enabled and the airflow Switch opens b Ignition terminal is energized c Ignition pilot valve terminal is not energized d Main valve terminal is not energized e Delayed main valve terminal is ener
21. 1 Short in modulator coil 1 Measure resistance per If proper resistances are Transformer circuit item B1 not observed replace No Voltage to modulator head or repair Amplifier wiring L Incorrect 1 Incorrect maximum 1 Check to see if heater is If desired temperature is Space discharge air temper delivering air at maximum not reached increase Temperature ature setting A1044 discharge air setting maximum discharge air temperature setting If desired space temper ature is not reached decrease minimum discharge air temperature setting If desired space temper ature is not reached with heater at high fire it may be undersized Consult factory If temperature reading is incorrect check items 25 26 amp 27 then recalibrate if necessary Control circuits external to Series 44 can cause burner malfunction Always check manual valve to be certain gas is on and check limit controls for normal operation 96 SECTION VIII MAINTENANCE SCHEDULE AND LUBRICATION REQUIREMENTS Periodic maintenance is essential to the efficient operation and extended service life of this equipment Failure to provide maintenance as recommended may void the equipment warranty A Maintenance Schedule 1 Weekly a Check that fan belts are tight and sheaves are aligned The fan belts can be checked every 30 days after the first 60 days of new belt run in CAUTION Do not overtighten belts 2 Monthly a C
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23. DC voltages the problem could well be in the wiring leading to the Discharge Air Sensor or the Discharge Air Sensor itself This should also be reviewed in the check list If the proper voltages are not obtained when wired as instructed the problem can be isolated to the electron ics and this may once again be reviewed in the check list After test remove the test resistor and reconnect the Discharge Air Sensor to terminals 3 and 4 If Remote Temperature Selector has been moved return it to its original position PRELIMINARY CIRCUIT ANALYSIS SYSTEM 44 This Preliminary Circuit Analysis will provide identifica tion of faulty components improper wiring or calibra tion and other difficulties when used with the tabulated Troubleshooting Guide NOTE All voltages and resistance readings are approximate Section 1 1 Wire the system per Figure 1 2 Connect a DC voltmeter to amplifier terminals 6 and 7 3 Turn the Test Potentiometer to minimum resis tance 2 000 ohms The DC voltage should read 0 volts 4 Turn the Test Potentiometer slowly to maximum resistance 12 000 ohms The DC voltage should gradually increase to at least 18 volts If proper voltages are observed continue on with Section 2 If proper voltages are not observed the problem is identified with the Amplifier the 24 volt AC power supply or the circuit connected to terminals 6 and 7 Section 2 1 Turn power OFF wire system per Figure
24. EL RESET BUTTON CAPTIVE MOUNTING SCREW FLAME E AMPLIFIER wa 15122 Figure 4 RM7895A B C D EC7895A C RM7896A B C D Relay Module Exploded View zo SECTION VII TROUBLE SHOOTING continued Figure 2 Wiring Subbase and Sequence Chart for RM7895A B EC7895A RM7896A B E LINE VOLTAGE ALARM ONES add 521 BLOWI BURNER CONTROLLER LIMITS LOCKOUT INTERLOCK INCLUDING AIRFLOW SWITCH EDEN gio PILOT IGNITION SERI MAIN FUEL VALVE S idi IGNITION 4 00 TIMED FOR DIRECT SPARK IGNITION OIL OR GAS IGNITION TRANSFORMER MAIN VALVE MASTER SWITCH L1 HOT PFEP POST PURGE PURGE 15 SEC STANDBY O PILOT Q FLAME Sf asm an SNNS Eme Gr L Ld 1 3 OPERATING INTERLOCKS serv swese locrourwrentoexotose OCD SIGNAL amm A RM7895 RM7896 120 VAC 50 60 HZ EC7895 220 240 VAC 50 60 HZ POWER SUPPLY PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED A DO NOT CONNECT ANY WIRES TO UNUSED TERMINALS A FOR EC7895 A 220 TO 240 VAC TO 120 VAC 10 VA MINIMUM STEPDOWN TRANSFORMER NOT PROVIDED MUST BE USED TO DRIVE THE SHUTTER FLAME DETECTOR SPECIFICATIONS FOR CORRECT WIRING A FoR RM7895A1048 ONLY IGNITION TERMINAL 10 do Z RM7896A B ONLY IS DE ENERGIZED WHEN FLAME IS PROVEN A AIRFLOW
25. P T plugged tapping accessible for test gauge connection must be installed immediately upstream of the gas supply connection to the unit WARNING To avoid equipment damage or possible personal injury do not connect gas piping to this unit until a supply line pressure leak test has been completed Connecting the unit before completing the pressure leak test may damage the unit gas valve and result in a fire hazard DANGER Never use an open flame to detect gas leaks Explosive conditions may exist which would result in personal injury or death The gas line should be supported so that no strain is placed on the unit Pipe compounds which are not soluble to liquid petroleum gases should be used on threaded joints The appliance and its individual shutoff valve must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures in excess of 1 2 PSIG The appliance must be isolated from the gas supply piping system by closing its individual manual shutoff valve during any pressure testing of the gas supply piping system at test pressure equal to or less than 1 2 PSIG Refer to the heater s rating plate for determining the minimum gas supply pressure for obtaining the maximum gas capacity for which this heater is specified 4 Une tuyauterie ad quatement dimensionn e doit tre pos e jusqu l unit Veuillez noter que la pression de la tuyauterie d alimentation en g
26. SWITCH CHECK FEATURE IS FOR THE RM7895B RM7896B M15123A SECTION VII TROUBLE SHOOTING co ntinued Figure 3 Wiring Subbase and Sequence Chart for RM7895C D EC7895C D RM7896C D l gt gt 2 pt tit ae PL BURNER MOTOR Ed 10 SEC INTERRUPTED aM PILOT IGNITION EH Q7800 FOR DIRECT SPARK IGNITION OIL OR GAS IGNITION TRANSFORMER MAIN VALVE LINE VOLTAGE BLOWER BURNER CONTROLLER LIMITS LOCKOUT INTERLOCK INCLUDING AIRFLOW SWITCH 6 9 00600020 MAIN FUEL VALVE S DELAYED 2ND STAGE MAIN VALVE 66 MASTER SWITCH 00 00 00 LED prep DISPLAY INITIATE STANDBY START Power Power Power Power rower O O O PILOT O O O O FLAME FLAME FLAME O man O O O alarm O ALARM ALARM O ALARM 1 BURNER C BUBNEHIBLOWERIMOTOB LA START mo c qr 0 s 00 Emm 0 0 a l ee j _ Oo o S S U OS TTT mE 1 OPERATING CO LIMITS AND BURNER CONTROLLER CLOSED mo A oe ue INTERLOCKS check LOCKOUT INTERLOCK CLOSED 6 7 sse a FLAME RM7895 RM7896 120
27. actory required supplied different from factory type of gas required type Note components may change 6a UV Sensor clean lens check Flame detection system not wiring and spark plug sensing pilot flame see spark 6b Flame Rod assure rod is in rod diagram P 001003 flame check wiring and flame rod No voltage on secondary side of 7 Check wiring or replace ignition transformer transformer if correct E If pilot does not light after Flame safeguard relay Run Test 1 Place in run position see prepurge has timed out switch in Test position or technical cut sheet on flame and there is no voltage at functioning problem safeguard relay flame safeguard relay output terminals If there is no heat with Manual gas shut off valve closed 1 Turn Heat Off On switch to Off pilot ok and voltage is position Slowly open all manual present at flame gas shut off valves before safeguard relay output restarting terminals No gas on outlet side of 2 Clear obstruction in vent orifice regualtors with inlet pressure ok line or replace if defective No gas on outlet side of valve or 3 Turn Heat Off On switch to Off actuator with inlet pressure ok postion After 7 seconds of prepurge pilot will light Then after 6 to 10 seconds main valve light will come on Check to see if all gas valves have opened If not check voltage at gas valve If voltage is found to be correct replace gas valve or actuator see Maxitrol troublesho
28. and 4 If inlet air sensor is being used disconnect and replace with a jumper On units where the Remote Temperature Selector is located a consid erable distance from the heater it may be advanta geous to connect the selector at the heater location Connect a DC volt meter capable of reading 0 24V DC on the Modulator or Modulator Regulator Valve terminals Set the temperature to the minimum dial setting The DC voltage should read 0 volts The DC voltage should gradually increase to at least 20 volts as you slowly rotate the dial to the maximum dial setting If these voltages are obtained the valve function can now be checked out The operation of the Valve with regard to voltage is as follows from 0 volts to approximately 5 volts the modulating valve should be on bypass flow with the heater operating on low or minimum fire From ap proximately 5 volts to 15 volts DC the valve should be performing its modulating function and the heater should be firing at a modulated flow rate between low and high fire depending upon the voltage Above approximately 15 volts DC the Valve should be delivering full flow to the heater and the unit should be on full fire If the DC voltage is obtained on the Valve terminals but the heater does not respond as de scribed the problem can be isolated to the valve itself or to the gas control manifold of the heater In the event proper voltages are obtained and the Valve responds correctly to these
29. at the Run Test Switch is in the RUN position before leaving the installation 10 SECTION VII TROUBLE SHOOTING continued SETTINGS AND ADJUSTMENTS Figure 6 Selectable Site Configurable Jumpers Selectable Site Configurable Jumpers The relay module has three site configurable jumper SELECTABLE CONFIGURATION JUMPERS RUN TEST SWITCH options see Fig 6 and Table 7 If necessary clip the ghee eds eee site configurable jumpers with side cutters and remove the resistors from the relay module SERVICE NOTE Clipping and removing a site configurable jumper enhances the level of safety Figure 5 Sequence Status LEDs RUN TEST SWITCH RM7895C D 8 CAPTIVE EC7895C ce RM7896C D 2 SCREW Hi ud 7 PLUG IN PURGE CARD M7553A COVER SEQUENCE STATUS n LEDs aa lt j c RELAY Table 7 Site Configurable Jumper Options 4 MODULE Jumper RESET m Number Description Intact Clipped AMPLIFIER Pilot Flame FLAME F hs a CURRENT A Establishing Period PFEP lens d SIMULATOR INPUT TEST JACKS M7552A JR2 Flame Failure Action Recycle Lockout JR3 Airflow Switch ILK Recycle Lockout Failure IMPORTANT Clipping and removing a jumper after 200 hours of operation causes a nonresettable Fault 110 The relay module must then be replaced WIRING SUBBASE RUN TEST 0 ONLY SWITCH CONFIGURATION JUMPERS SEQUENCE STATUS LED PAN
30. ation Maximum or location temperature reading at where average temper Minimum TS144 with average ature can be sensed Discharge Air discharge air temperature Temperature 2 Incorrect discharge air Follow procedures outlined If proper temperatures are not observed refer to Discharge Air Temperature calibration procedures G Continuous High Fire Electronics OK 1 Foreign material holding valve open 2 Plunger jammed Remove bottom plate and inspect valve and seat Inspect plunger should be smooth and clean and operate freely in solenoid Sleeve Clean replace valve and or seat if necessary Clean or if necessary replace plunger H Continuous High Fire Electronics Problem 1 Open circuit in T8144 Measure resistance per item C3 If readings are incorrect replace the TS144 or repair wiring Control circuits external to Series 44 can cause burner malfunction Always check manual valve to be certain gas is on and check limit controls for normal operation 25 Series 44 Room Temperature Control continued TROUBLESHOOTING GUIDE Reproduced with permission from Maxitrol Company Symptom Possible Cause Field Test Remedy Incorrect High Fire 1 Inlet pressure too low Incorrect outlet pressure adjustment 1 Read inlet pressure at valve using a manometer with heater operating at full fire Pressure
31. az doit correspondre celle sp cifi e sur la plaque d identification lorsque l unit fonctionne plein rendement Refer to the heater s rating plate for determining the maximum supply pressure to the heater Correctly sized piping must be run to the unit Please note that gas line pressure must be as shown on specification plate when unit is operating at full input F Field Wiring and Remote Control Installation Connect the power lines to the line side of the main disconnect switch 2 Mount and wire remote control panel thermostats temperature sensors and any other field installed controls as indicated on the unit control wiring diagram 3 Connect the wires to the appropriate field wiring terminals as indicated on the unit control wiring diagram 4 the optional low temperature limit was not an integral part of the heater the factory recommends that a low temperature limit control be installed in areas where freeze protection is needed in the event of burner shut down 5 Field wiring shall have a temperature rating of at least 105 C The minimum size of the supply cable circuit shall be sufficient for the maximum ampacity of the heater L installation l ctrique d utilisateur aura une temp rature qui value d au moins 105 C La minimum de source du circuit de c blage sera suffisante pour le ampacity maximum de l appareil de chauffage G Locating Temperature Controls The room or outdoor thermo
32. beams and stand pipes to insure that clearance dimensions coincide with those of the unit The minimum clearance to combustible material must be maintained as listed in Table 1 Table 1 Minimum clearance to combustible material also consult local codes and regulations Clearances to Combustible Material Vertical Units Horizontal Units Front 39 inches 39 inches Rear 6 inches 6 inches Right 6 inches 6 inches Left 6 inches 6 inches Top 12 inches 12 inches Floor Zero 6 inches Consider control side as front of unit Optimum clearance for shaft removal would be equivalent to cabinet width On outdoor curb mounted installations flash and seal the roof curb to prevent leakage The cross section of factory provided curb is formed to accept wood nailing strip and insulation provided by others Make a visual inspection to insure no damage has occured to the unit during installation C Location of Accessories Where applicable standard or optional accessories will be placed inside the fan section of the unit for shipment and must be removed and installed by the mechanical or electrical contractor Remotely located discharge or inlet dampers must be equipped with an end switch and interlocked to insure maximum design opening before starting and running circuits may be energized Field constructed intake accessories should be properly designed to minimize the entry of rain and snow Adequate building
33. ce instructions thoroughly before installing or servicing this equipment AVERTISSEMENT Une installation d ficiente de m me qu un mauvais r glage modification entretien ou maintenance peuvent occasionner des dommages mat riels corporels voire causer la mort Lire attentivement les instructions d installation d utilisation et d entretien avant d installer ou d intervenir sur cet appareil WARNING Install operate and maintain unit in accordance with manufacturer s instructions to avoid exposure to fuel substances or substances from incomplete combustion which can cause death or serious illness The state of California has determined that these substances may cause cancer birth defects or other reproductive harm INSTALLER S RESPONSIBILITY Installer Please Note This equipment has been test fired and inspected It has been shipped free from defects from our factory However during shipment and installation problems such as loose wires leaks or loose fasteners may occur It is the installer s responsibility to inspect and correct any problems that may be found a Er L IIN 6 4830 Transport Drive Dallas TX 75247 Phone 214 638 6010 Fax 214 905 0806 HVAC PRODUCTS www sterlinghvac com SECTION I FORWARD As is the case with any fine piece of equipment care must be taken to provide the proper attention to the operation and maintenance details of this machine This manual of
34. ck the control inlet pressure using a manometer at the inlet pressure tap of the control Take the necessary steps to provide proper gas pressure to the control SECTION VII TROUBLE SHOOTING continued Check Safety Shutdown Performace WARNING Fire or explosion hazard Can cause property damage severe injury or death Perform the safety shutdown test any time work is done on a gas system NOTE Read steps 1 through 7 before starting and compare to the safety sutdown or safety lockout tests recommended for the intermittent pilot IP ignition module Where diffferent use the procedure recommended for the module 1 Turn off gas supply 2 Set thermostat or controller above room tempera ture to call for heat 3 Watch for ignition spark or for glow at hot surface igniter either immediately or following prepurge See IP module specifications 4 Time the length of the spark operation See the IP module specifications 5 After the module locks out open the manual gas cock and make sure no gas is flowing to the pilot or main burner With modules that continue to spark until the pilot lights or the system shuts down manually the pilot should light when the manual gas control knob is opened 6 Set the thermostat below room temperature and wait one minute 7 Operate system through one cmplete cycle to make sure all controls operate properly 15 SECTION VII TROUBLESHOOTING continued System with Pilot
35. d replacing air filters applies twelve months of the year where blowers are used for ventilation and heating 98 D Belt Tensions and Adjustments Belt tension is adjusted during the initial run in and test periods at the factory However the belts are run as slack as possible to prevent excessive damage to the bearings yet tight enough to prevent slippage It is necessary therefore to tighten all belts during the first few months of operation and to check for proper tension weekly during the first 60 days after which 30 day check intervals are sufficient NOTE Turn off all power to the equipment before checking belt tensions CAUTION Do not attempt to tighten any belt or belts by changing the pitch of an adjustable pulley as this will change the speed of a driven pulley causing the unit to be rendered OUT OF AIR BALANCE Do not overtighten belts Suggested Belt Tension Method 1 Check tension frequently during the first 24 48 hours of run in operation Ideal tension is the lowest tension at which the belt will not slip under peak load conditions Over tensioning shortens belt and bearing life 2 To properly tension a conventional V belt drive use the following procedure a Measure the span length b At the center of the span apply a force perpen dicular to the span to deflect the belt 1 64 inch for every inch of span length For example for a 40 inch span apply a force that will deflect the belt 40 64
36. d the hold condition exists for four min utes the RM7895A B C D EC7895A C RM7896A B C D locks out SECTION VII TROUBLE SHOOTING continued Causes for hold conditions in the INITIATE sequence 1 AC line dropout detection 2 AC line noise that can prevent a sufficient reading of the line voltage inputs 3 Low line voltage brownouts The INITIATE sequence also delays the burner motor starter from being energized and de energized from an intermittent AC line input or control input Standby The RM7895A B C D EC7895A C RM7896A B C D is ready to start an operating sequence when the operat ing control input determines a call for heat is present The burner switch limits operating limit control and all microcomputer monitored circuits must be in the correct state for the relay module to continue into the PREPURGE sequence Normal Start Up Prepurge The RM7895A B C D EC7895A C RM7896A B C D Relay Module provides PREPURGE timing selectable from two seconds to thirty minutes with power applied and the operating control indicating a call for heat 1 The Airflow Interlock burner switch Run Test switch and all microcomputer monitored circuits must also be in the correct operating state 2 The motor output terminal 4 is powered to start the PREPURGE sequence 3 The Airflow Interlock input closes ten seconds into PREPURGE or within the specified purge card timing otherwise a recycle to the beginning of PREPURGE or locko
37. dous in the presence of flammable solids liquids and gases explosive materials such as grain dust coal dust gunpowder etc substances such as refrigerants or aerosols which may become toxic when exposed to heat or flame Recirculation is not recommended in uninsulated buildings where outside temperatures fall below 32 F 0 C Excessive recirculation or insufficient ventilation air which results in inadequate dilution of combustion products generated by the heater may create hazard ous concentration of carbon monoxide nitrogen dioxide and other combustion products in the heated space If gas fork trucks or other fossil fuel powered equip ment are utilized in the conditioned area additional ventilation requirements for the facility must be ad dressed separately The heater inlet shall be located in accordance with applicable building code provisions for ventilation air Field constructed intake accessories should be properly designed to minimize the entry of snow and rain All ventilation air to the heater shall be ducted directly from the outdoors If in doubt regarding the application consult the heater manufacturer ETL labeled heaters must be equipped with a control system and an air measuring station provided by the heater manufacturer and installed on the return air damper or duct 34 35 2 TN NA f CIAL IN HVAC PRODUCTS 4830 Transport Drive Dallas TX
38. e TS114 if necessary If items B1 3 check out and modulating voltages are still not obtained amplifier may be assumed faulty Replace C Continuous Low Fire Electronics OK Short circuit or open circuit in Modulator Coil Plunger missing jammed or improperly installed Measure resistance across modulator terminals with connecting wires detached Inspect Plunger should be installed to operate freely in solenoid sleeve Replace modulator head if not approximately 45 55 ohms for M611 Valve and 60 80 ohms for MR212 Valve Clean or replace plunger if necessary D Incorrect Minimum Fire Erratic or Pulsating Flame Incorrect by pass metering valve adjustment Excessive negative burner pressure See valve adjustments in Section IX Close main gas supply and measure manifold pressure with blower operating Reading should be less than 1 5 w c negative pressure Adjust to proper minimum fire If reading is greater than 1 5 negative pressure check for clogged filters or other inlet air restrictions Consult factory for other solutions E Continuous High Fire Electronics Problem Short circuit in TD114 Remote Temperature Selector circuit or wiring Open circuit in TS114 TS1007 Discharge or Inlet Air Sensor circuit or wiring Jumper not connected across amplifier terminals 2 amp 3
39. equipment should not attempt the initial adjustment and checkout procedure which is essential before such installations may be considered ready for operation This manual should be made readily available to all operating personnel as an aid in troubleshooting and proper maintenance B Shipping Base Direct Gas Fired units are shipped completely assembled where shipping limitations allow Optional inlet hoods filter and or damper sections or other large accessories are assembled and shipped mounted and wired whenever possible within limita tions of shipping and handling Any optional accesso ries shipped separately are shipped as assembled sections Any wired accessories which have been disassembled for separate shipment require no additional conduit or wire for field reassembly All wire leads will be tagged for ease of reconnection in the field Shipments are made F O B Dallas Texas by flatbed truck The unit is securely strapped tied and blocked to prevent shipping damage All shipments are checked by an inspector before they are accepted by the carrier Parts that are shipped unmounted are noted on the bill of lading These parts where feasible are packaged and shipped with the units Upon receipt of shipment all units should be checked against the bill of lading to insure all items have been received All equipment and any optional accessories should be checked carefully for physical damage in the presence of the carrier
40. et the ignition control D Air Pressure Switches The high air pressure Switch is checked by removing the sensing tube from the entering air side of the burner Switch operation will shut off the burner Recycle is automatic when the sensing tube is replaced The low air pressure switch is checked by removing the sensing tube from the leaving air side of the burner Switch operation will shut off the burner Recycle is automatic when the sensing tube is replaced When checking operation of air pressure switches on systems without pilot the heat Switch will have to be turned off for approximately five seconds to reset the ignition control E Adjustable temperature and limit Controls The limit controls are checked by adjusting control settings to a lower temperature setting while the unit is operat ing on high fire and observing cutoff The controls should be reset to settings shown below Suggested Control Settings TC 01 Room Thermostat Customer Discretion RE 26 High Limit Discharge Ductstat 95 F TC 03 On Off Inlet Ductstat 65 F RE 26 Low Limit Discharge Ductstat 55 F TC 08 Freeze 45 F TC 09 Night Set Back Room Customer Discretion TC 52 Remote Temperature Selector eset ecce Customer Discretion PS 04 Low Gas Pressure Switch 1 0 W C PS 07 High Gas Pressure Switch
41. gized f No flame present at end of MFEP g Internal system fault occurred h Purge card is removed i Purge card is bad 6 RUN PERIOD a No flame present b Airflow lockout feature is enabled and the airflow Switch opens c Interrupted pilot valve terminal is energized RM7895C D EC7895C RM7896C D d Main valve terminal is not energized e Delayed second stage main valve terminal is not energized RM7895C D EC7895C RM7896C D f Internal system fault occurred g Purge card is removed h Purge card is bad OPERATION Sequence of Operation The RM7895A B C D EC7895A C RM7896A B C D has the operating sequences listed below see Fig 2 and 3 The RM7895A B C D EC7895A C RM7896A B C D LED provide positive visual indication of the program sequence POWER PILOT FLAME MAIN and ALARM Initiate The RM7895A B C D EC7895A B C RM7896A B C D Relay Module enters the INITIATE sequence when the relay module is powered The RM7895A B C D EC7895A C RM7896A B C D can also enter the INITIATE sequence if the relay module verifies voltage fluctuations of 10 15 or frequency fluctuations of 10 during any part of the operating sequence The INITIATE sequence lasts for ten seconds unless the voltage or frequency tolerances are not met When not met a hold condition is initiated and displayed on the optional KDM for at least five seconds when met the INITIATE sequence restarts If the condition is not corrected an
42. heck all valves piping and connections for leaks b Check the flame signal c Check the fuel pressure in the fuel supply line to each heater d Check the burner manifold pressure at full fire and that low fire has a continous flame all across burner Clean the flame sensor s Inspect filters Clean or replace as necessary Inspect the main fan bearings Check all dampers damper actuators and linkages Adjust and tighten if necessary i Ensure that there are no obstruction blocking the air supply to the heater or the air discharge from the heater j Inspect the area and make sure that no combustible or hazardous material has been stored within the clearances as shown on the unit nameplate 3 Quarterly a Complete the monthly maintenance schedule b Check the belt tension for the main fan s and adjust if necessary c Check the alignment of the sheaves and adjust if necessary d Inspect all bearings set screws for tightness and lubricate bearings if necessary e Check the pilot electrical system if applicable Adjust if necessary f Check the pilot assembly if applicable Clean and adjust if necessary g Inspect the burner carefully Clean and adjust if necessary h Check voltages and amp draw on main fan motor i Check the operation of all safety controls individually j Check the operation of the automatic gas shut off valves and check them for leakage at the pressure test ports provided 4 Off
43. here a regulator has been installed to reduce the inlet pressure to 5 PSIG or less remove dust cap of main gas regulator and turn adjusting screw clockwise to increase pressure or counter clockwise to decrease pressure Connect test instrument to pilot flame test jack located on flame safeguard relay Set all thermostats to call for heat Set inlet ductstat if applicable above outside air temperature Open pilot and first main gas shut off valves slowly Last main gas shut off valve before burner must remain closed at this time Reset high low gas pres sure switches if applicable Check pilot and main gas lines for leaks Turn Fan and Heat Off On switches to On position Blower fan will run Unit will run for 7 seconds before ignition trial if all safety and limits are made NOTE 3 OR 4 TRIALS MAY BE NEEDED TO PURGE AIR FROM PILOT LINE IF BURNER HAS MAIN FLAME ROD OR SCANNER YOU MAY NEED TO DISABLE TIMER CIRCUIT Honeywell Flame Safeguard Control Watch D C voltmeter carefully The reading should be steady and between 2 0 to 5 0 volts D C If the reading is too low slowly turn the needle valve in or out until satisfactory readings are obtained NOTE Pilot regulator adjustment may be needed if the adjustment of the needle valve does not yield the required reading When pilot is adjusted shut the burner off by turning the Fan Off On switch to Off Setting Main Flame Install manometer at test port on the last
44. ing combustion The presence of these hairline cracks in no significant way affects the combus tion efficiency or performance of the heater Should a large opening develop it may cause difficulties in cross ignition of flame across the face of the burner If this does occur the specific mixing plate or plates involved must be replaced c Put system back into operation and view burner while cycling through full firing range This will give a visual check for blocked burner ports 2 Inspect the flame rod and ignition electrode for dirt and moisture Wipe off if necessary Examine for any evidence of premature arcing If in doubt check continuity of flame rod to be sure it is not grounding out Replace if required The porcelain on the ignition electrode must be intact not cracked The spark gap should be between 1 16 and 3 32 of an inch 3 Replace all access panels which have been removed and operate the unit for a test period Check for normal response and function of all controls 4 Check all gas piping for possible leaks using a soap bubble solution 5 Inspect the support means to be sure that every thing is firmly anchored in place MAXON NP I AIRFLO BURNERS Inspection and Maintenance of Gas Ports Conduct initial inspection within the first month after commissioning Visually check the gas ports of new burner assemblies for any piping scale or debris Use Pin Vise with drill bit to remove Annual inspection
45. kets are used on doors inspection covers some filter racks and some outdoor air dampers Inspect gaskets periodically and repair or replace as required 29 G Heater 1 Atleast a yearly inspection is recommended for heating installations and more frequently for process applications in year round operation Your own experience is the best guide in determining frequency of inspection but as a minimum the following procedure should be followed a Shut the system down totally disconnect ing or locking out power supply so there can be no accidental start up during inspection b Inspect the burner carefully including upstream and downstream sides of mixing plates as well as burner body face Note that complete burner assembly may have to be removed for proper inspection and cleaning Any accumulation of scale or foreign material on either side of the mixing plates should be removed with a wire brush Check visually that no holes in the mixing plates are blocked If any burner ports are plugged even partially clear them with a piece of wire See Maintenance of Gas Ports WARNING Do not enlarge burner ports or performance may be drastically affected If any mixing plates are loose or missing fasteners tighten replace as necessary Always use zinc plated or stainless fasteners The mixing plates on the burner may display hairline cracks These cracks are normal and caused by thermal stresses occurring dur
46. n established the control will shut off the gas valve within 0 8 seconds and locks out If flame is sensed during a purge period when no flame should be present the control will remain in purge with the gas valve off until the false flame disappears If the gas valve is found to be powered when it should be off or not powered when it should be on the control will enter lockout with all outputs off Reset is accomplished by cycling the power off for a minimum of 5 seconds Honeywell Two Stage Valve Two stage models require that you check and adjsut both high and low pressure regulator settings Two stage appliance operating sequences vary Consult the appliance manufacturer instructions for the specific operating sequence and regulator adjustment proce dure for the appliance in which the control is installed 1 Set appliance to operate on high 2 Carefully check the main burner lightoff Make sure that the main burner lights smoothly and that all ports remain lit 3 Check the full rate high manifold pressure listed on the appliance nameplate for high pressure The gas control full rate outlet pressure should match this rating 4 14 With main burner operating check the gas control flow rate using the meter clocking method or check pressure using a manomeer connected to the outlet pressure tap on the gas control If necessary adjust the high pressure regulator to match the appliance rating a Remove the pres
47. ngs seized 10 Check and replace 11 Motor may be burned or 11 Turn power off and check motor incorrectly wired and wiring 12 Motor overheating 12 Check burner firing rate B Ifthere is no voltage 1 Heat Off On switch in Off 1 Switch to On position ignition control position 2 Burner enable relay open if 2 Check for power and replace if applicable necessary 3 Outside air temperature higher 3 Lower On Off inlet ductstat than On Off inlet ductstat if setting applicable 4 Field purge timer open if 4 Check for power and replace if applicable necessary C Burner does not light 1 Manual gas shut off valve closed 1 Slowly open valve after 5 seconds pre 2 Inlet gas pressure lower than 2 Increase gas pressure purge of flame safeguard required gas pressure relay and there is voltage 3 Type of gas Natural LP 3 Replace with factory required at ignition control supplied different from factory type of gas required type 4 Auxiliary switch on starter not 4 Check for power and replace if closed necessary 5 Air flow switches not closing 5 Adjust the air flow and external static pressure to match rating plate 6 High temperature limit switch 6 Correct problem Reset by open pushing down the reset button 7 High or low gas pressure 7 Correct problem Reset both switches open if applicable Switches 8 Main gas valve relay open 8 Check for power and replace if necessary 18
48. or 5 8 of an inch c Compare the force you have applied with the values given in the table below If the force is between the values for normal tension and 1 1 2 times normal tension the belt tension should be satisfactory If the belt tension is not within this range it can be adjusted by loosening the motor mounting bolts and adjusting the position of the motor along its base NOTE A new drive can be tightened to two times the minimum value shown to allow for normal drop in tension during the run in period B Section small Pounds pulley Pounds Force for diameter Belt Force for 1 times range in Manufacturer Normal Normal Inches amp Type Belt Tension Tension 3 4 4 2 Gates Hi Power 4 4 6 6 4 4 4 6 Gates Hi Power 4 9 7 4 5 8 8 6 Gates Hi Power 5 8 8 7 Note For recommendation of other types of belts consult respective manufacturers E Optional Coils And Related Items 1 Coils Coil surfaces must be kept clean of dirt and lint in order to operate at rated efficiency Coils should be inspected on a regular basis and cleaned as required CAUTION Solutions used to clean coils must not be corrosive to metals or materials used in the manufacturer of this equipment If cleaning solutions are applied through means of high pressure spray care must be taken to avoid damaging the coil fins 2 Condensate Drain Pan Periodically flush the condensate pan and drain system with a water hose F Gaskets Gas
49. oting Guide for modulating valve Main flame rod or scanner not 4a Check burner for low fire sensing main burner adjustment 4b UV Sensor clean lens and check wiring 4c Flame Rod be sure flame rod is in main flame check wiring and flame rod G If there is no heat with Flame safeguard relay Run Test 1 Place in Run position see technical cut sheet on flame safeguard relay by System without Pilot TROUBLESHOOTING GUIDE Symptom Cause Remedy A If blower does not 1 Low or no voltage 1 Check power source operate 2 Fuse s blown 2 Check and replace 3 Customer interlock not closed or 3 Close or connect customer connected interlock 4 Fan Off On switch in Off position 4 Switch to On position 5 Time clock night setback 5 Check time clock night setback thermostat or field installed thermostat and field installed controls open controls for proper settings 6 Freeze protection tripped 6 Reset freeze stat by interrupting power Check for proper setting and burner operation 7 Damper motor not operating or 7 Check for power at damper motor its end switch not making and that end switch has been wired correctly to the N O normally open contact Check that the linkage is clear and not binding 8 Overload protection on motor 8 Push reset button on starter and starter tripped check amps 9 Belts loose or broken 9 Turn power off and check belts 10 Beari
50. ow and external static pressure to match the rating plate 4 Outside air temperature higher 4 Check stat for proper setting than on off inlet ductstat setting if applicable 5 High temperature limit thermostat 5 Reset control and correct prob open lem before restarting 6 High low gas pressure switch 6 Check gas pressure and reset open Switch 7 Field purge timer open 7 Check for power or replace if necessary C Ifthe flame safeguard 1 See technical cut sheet on flame 1 Determine the cause of lockout relay goes into saftety safeguard relay Push reset button on flame shutdown lockout safeguard relay D If pilot does not light after 1 Manual pilot shut off valve closed 1 Slowly open valve prepurge has timed out 2 Inlet gas pressure lower than 2 Increase gas pressure 10 seconds and voltage required gas pressure is present on flame 3 No gas through pilot regulator 3 Clear obstruction in vent orifice safeguard output with inlet gas pressure ok line or replace if defective terminals 4 No gas through pilot solenoid 4 Check for correct installation and voltage Correct or replace SECTION VII TROUBLESHOOTING continued System with Pilot continued pilot ok and no voltage is present at flame safeguard relay output terminals switch in Test position or fucntioning problem Symptom Cause Remedy D continued Type of gas natural LP 5 Replace with f
51. relay module is now in RUN and remains in RUN until the controller input terminal 6 opens indicating that the demand is satisfied or a limit has opened Post Purge RM7896A B C D Only After demand is satisfied or a limit opens de energizing terminal 6 the Ignition Pilot valve main valve and delayed main valve terminals 8 9 and 21 are de energized The blower motor terminal 4 remains powered for 15 seconds Run Test Switch RM7895C D EC7895C RM7896C D only The Run Test Switch is located on the top side of the relay module see Fig 5 The Run Test Switch allows the burner sequence to be altered as follows 1 In the measured PREPURGE sequence the Run Test Switch placed in the TEST position causes the PREPURGE timing to stop 2 Inthe Pilot Flame Establishing Period the Run Test Switch placed in the TEST position stops the timer during the first eight seconds of a ten second PFEP selection or during the first three seconds of a four second PFEP selection It also allows for pilot turn down test and other burner adjustments This activates a fifteen second flameout timer that permits pilot flame adjustment without nuisance safety shutdowns The Run Test Switch is ignored during PFEP for the C and D relay modules if terminals 8 and 9 or 9 and 21 are jumpered IMPORTANT When the relay module is switched to the TEST mode it stops and holds at the next Run Test Switch point in the operating sequence Make sure th
52. relief must be provided so as to not over pressurize the building when the heater is operating at its rated capacity This can be accom plished by taking into account through standard engineering methods the structure s designed infiltra tion rate by providing properly sized relief openings by interlocking a powered exhaust system or by a combination of these methods D Electrical Connections WARNING Open all disconnect switches and secure in that position before wiring unit Failure to do so may result in personal injury or death from electrical shock WARNING Controls must be protected from water Do not allow water to drip on the ignition system NOTE Before installing any wiring check the unit rating plate for supply power rating All electrical connections must conform to the current edition of ANSI NFPA No 70 National Electrical Code and applicable state and local codes in Canada to the Canadian Electrical Code Part 1 CSA Standard C22 1 and applicable provincial and local codes Since shipment of unit may require disassembly after factory check and test reconnection of some electrical devices will be required in the field Connect electrical wires supplied in factory furnished conduit to appro priate terminals All leads are tagged to facilitate field connections See wiring diagram provided with equip ment Complete all wiring to any optional accessories as shown on unit bill of material and elect
53. rical wiring diagram as required before applying voltage to the unit Entry location for all field installed and control wiring is through the control panel If optional disconnect is not furnished with heater the field provided disconnect must be of the proper size and voltage Refer to unit nameplate for minimum circuit ampacity and voltage The disconnect must be installed in accordance with Article 430 of the current edition of ANSI NFPA No 70 National Electrical Code Check the supply voltage before energizing the unit The maximum voltage variation should not exceed 10 Phase voltage unbalance must not exceed 2 NOTE Should any original wire supplied with the heater have to be replaced it must be replaced with wiring material having a temperature rating of at least 105 C REMARQUE Dans le cas ou un quelconque des cables livr s avec l unit devait tre remplac il doit tre remplac avec des c bles pr vus pour r sister une chaleur d au moins 105 C E Field Piping All gas piping must be in accordance with the require ments outlined in the National Fuel Gas Code ANSI Z223 1 It is required that a ground union be installed adjacent to the manifold for easy servicing A drip leg and or filter should be provided upstream of the unit s inlet gas connection An additional shut off must be located external of the unit s enclosure The location of this valve must comply with all local codes A 1 8 inch N
54. ronze sleeve motors or equal bearings Fractional HP ODP TEFC or TEAO Recommendation See following note Fractional HP Century G E Bronze sleeve single phase equal bearings ODP or TEFC Recommendation See following note Fan shaft Browning Self aligning bearings or equal single row or double row roller or ball bearings resilient mounted Recommendation See following note Mestek Sleeve or equal Recommendation See following note Dampers 27 1 Blower Motors Some motors require lubrication while others do not Those that require lubrication can be identified by the presence of grease plugs in the motor casing at each end Motors that do not have grease plugs cannot be greased and are lubricated for the life of the motor bearing Lubrication of motors should be done while the motor is warm and at a standstill Remove and clean all grease plugs and insert a grease fitting in the upper hole in the motor casing at each end Viewed as if motor were sitting horizontally on its base There may be one or two plugs in each end casing of the motor Add a small amount of a clean good grade ball bearing grease such as Exxon Polyrex EM or equal with a low pressure grease gun Run the motor five minutes before removing the grease fittings and replacing the plugs CAUTION An excess of grease will overheat the bearings NOTE On totally enclosed fan cooled TEFC motors the rear end
55. s are normally adequate once the initial piping debris is removed The operating conditions of the burner will determine how frequently maintenance is actually required Use of an electric drill motor is not suggested unless both Pin Vise and Drill as shown can be chucked up a vari speed drill unit Use caution because it is easy to snap the bits off in a port when using a drill motor Removal of broken bits from the gas ports is difficult Alternate drill sizes which may be used are 5 64 for 47 and 1 16 for 50 Contact your Maxon representative to answer questions or address any problems Pin Vise NP amp RG AIRFLO 1 n Burner Body Mixing Plates Not Shown Gas Ports All aro 47 Drill Size Exception is several 50 holes at the intersection of 12 X6 Tee s amp S6Bl s 450 47 Holes En TN benedi 12 X 6 Tee Sections All Straight Sections 12 18 24 30 SECTION IX MAXITROL VALVE ADJUSTMENTS AND PRELIMINARY CIRCUIT ANALYSIS MR212 Valve M411 511 611 Valve High Fire Manifold Adjustments High Fire Manifold Adjustments 1 Disconnect wires from amplifier terminal 4 Series 1 Disconnect wires from amplifier terminal 4 Series 14 or 2 and 4 Series 44 This causes the 14 or 2 and 4 Series 44 This causes the valve to call for continuous high fire valve to call for continuous high fire 2 Remove seal cap
56. s representative If parts are missing or damage has occurred a claim should be filed immedi ately with the carrier All Direct Gas Fired units are given a complete opera tions test and control circuit checkout before shipment Copies of the wiring diagram piping diagram and bill of material are included with each unit shipped If correspondence with the factory is necessary please provide the unit model and serial number C Optional Factory Service Periodic service on any piece of mechanical equip ment is necessary for efficient operation A nationwide service support network is available to provide quick and dependable servicing of make up air heating ventilating or air handling types of equipment Factory start up service is also available which includes the presence of a service engineer to supervise the initial start up and adjustment of the equipment and provide instructions for the owner s maintenance personnel in proper operations and maintenance Consult factory for quotations on start up or periodic service SECTION Ill INSTALLATION FOR CANADIAN INSTALLATIONS ONLY 1 All installations must conform with local building codes or in the absence of local codes with current CAN CGA B149 Installation Codes For Gas Burning Appliances and Equipment 2 All electrical connections must be in accor dance with Canadian Electrical Code Part 1 CSA Standard C22 1 This equipment must be installed and wired in
57. should be at least equal to the sum of outlet pressure setting and pressure drop of the valve plus 1 0 w c 2 Read outlet pressure using manometer and compare with the pressure stated on the specification plate 1 Increase inlet pressure if possible or change to larger valve Consult factory about possibility of using special spring to reduce pressure drop on selected installations See Valve Adjustments Section IX Incorrect minimum discharge air temper ature setting A1044 Insufficient burner capacity Incorrect space temperature calibra tion 2 Check to see if heater is delivering air at minimum discharge air setting 3 Check to see if heater is operating at high fire 4 Place thermometer next to T244 or TS244 Compare space temperature reading with T244 or TD244 dial setting J Continuous 1 Faulty amplifier 1 Follow procedures outlined Ir amplifier is proven at Maximum in Preliminary Circuit fault install replacement Discharge Air Analysis in Section IX amplifier Temperature 2 Open circuit in T244 or 2 Measure resistance per If reading is incorrect TS244 TD244 item E2 replace T244 TS244 TD244 or repair wiring 3 Incorrect space 3 Follow procedures outlined If proper action is obtained temperature calibra in Preliminary Circuit first check item 22 tion Analysis in Section IX Recalibrate if necessary K Burned out
58. sion from Maxitrol Company range of mod ulating voltage at terminals 3 amp 4 automatic valve terminals 5 and 6 If 24V AC check for open circuit to automatic valve Symptom Possible Cause Field Test Remedy Incorrect 1 Inlet Air sensor is Inlet Air Sensor changes Sensed temperature will Discharge Air used 1 for each 3 5 5 or 8 vary from TD114 dial Temperature outside temperature settings This is intentional change from 60 predeter mined turndown varies with model used 2 Incorrect wiring Check wiring diagram for Correct wiring heater 3 System out of Sensed temperature Seecalibration procedure calibration thermometer next to TS114 does not correspond to TD114 setting 4 Improper TS114 Sensed temperature Move TS114 to location location thermometer next to where average repre TS114 does not represent sentative temperature can average discharge air be sensed temperature 5 Room Override Remove Override TD114 dial setting then Thermostat circuit Thermostat lead from check thermostat setting closed terminal 2 of TD114 and or check wiring for shorts J Burned out 1 Short circuit in Measure resistance across Replace modulator head if Transformer modulator coil modulator terminals with less than 40 ohms red lead wires discon nected 2 Short circuit between Inspect wiring Correct wiring if short is amplifier and found modulator val
59. stats should be mounted where they will not be subjected to direct impact of the heated air or radiant heat from the sun It is also recommended that thermostats especially those with mercury bulb contacts be mounted on a vibration free surface The side of building columns away from the heater or interior walls are usually the location best suited for mounting thermostats Controls with outdoor bulbs require that the outdoor bulb be shielded from direct radiation from the sun Unit mounted sensors are factory located and mounted SECTION IV PRE START UP A Pre Start Up 1 Theowners representative or equipment operator should be present during start up to receive instruc tions on care and adjustments of the equipment All equipment has been factory tested adjusted metered and inspected to meet conditions set at the time the order was placed Only minimal adjustments should be required All information in this service manual is typical All products are semi custom and changes may occur Suggested Tools and Instruments Volt Ohm Meter Thermometer Tachometer Ammeter Manometer 0 10 W C Microammeter Standard Hand Tools D C Volt Meter Gas Pressure Gauge 0 35 Ibs NOTE All servicing and adjustments of the Direct Gas Fired unit should be performed by a qualified service engineer CAUTION Line side of disconnect may be energized 2 Remove all shipping blocks brackets and bolts from supply fan base with optional isola
60. sure regulator adjustment cap b Using a screwdriver turn the inner adjustment screw for HI pressure clockwise lt w to increase or counterclockwise de crease the gas pressure to the burner After high ressure has been checked check low pressure regulation Two stage appliance operat ing sequences vary Consult the appliance manu facturers instructions for the specific operating sequence and regulator adjustment procedure for the appliance in which the control is installed and for instructions on how to prevent the control from moving to high stage while checking the low pressure regulator setting Check the low rate manifold pressure listed on the appliance nameplate Gas control low rate outlet pressure should match this rating With main burner operating check the gas control flow rate as before using the meter clocking method or check pressure using a manometer connected to the outlet pressure tap on the con trol If necessary adjsut the low pressure regulator to match the appliance rating a Remove the pressure regulator adjustment cap b Using a screwdriver turn the inner adjustment screw for LO pressure clockwise w to increase or counterclockwise to de crease the gas pressure to the burner Once high and low pressure have been checked and adjusted replace pressure regualtor adjust ment cap If the desired outlet pressure regulator or flow rate cannot be achieved by adjusting the gas control che
61. t height in feet SCFM rating plate air throughput Refer to the electrical schematic for the proper circuit placement Purge timer P N 65 0711 00 SECTION V UNIT START UP GENERAL Make sure all doors and service panels have been closed or replaced Turn main disconnect switch off Check the incoming line voltage to match unit nameplate rating If voltage is over 10 of nameplate rating or phase voltage unbalance is over 2 notify contractor or power company Turn main disconnect switch on Turn Fan Off On switch to On position Damper opens if applicable Blower fan turns on Turn Fan Off On switch to Off position Check supply blower for proper rotation NOTE To change rotation of the blower simply interchange any two 2 of the line leads of the motor starter for three 3 phase motors On single phase motors refer to motor nameplate Turn Fan Off On switch to On position Check for proper blower rpm Check that all motor amp draws do not exceed nameplate ratings and overloads are set to motor nameplate amps Check all dampers for proper operation and linkage does not bind see Sequence of Operation Make sure all manual gas valves are closed Turn Fan and Heat Off On switches to On position Blower fan will run and burner will fail to light Reset flame relay Turn Fan and Heat Off On switches to Off position Unit Start Up Systems with Pilot NOTE To adjust gas pressure on supply lines w
62. tance K N Delivered air temperature should be per A1044 RESISTOR l I MAX temperature setting Turn Test Potentiometer to minimum resistance Delivered air temperature should be per A1044 MIN temperature setting If proper delivered air temperatures are observed the problem is identified with the space temperature sensing and or temperature selecting components JUMPER and circuits See Troubleshooting Guide If proper delivered air temperatures are not observed check calibration See Troubleshooting Figure 2 Guide 14V20VA 2K RESISTOR JUMPER Section 5 1 After test remove all test equipment and reconnect all components SECTION X REPLACEMENT PARTS Replacement parts may be ordered from the factory When parts are ordered MODEL NUMBER SERIAL All warranty parts will be shipped freight allowed from NUMBER FACTORY ORDER F O and PART factory for normal ground service Warranty parts must be NUMBERS are required Belts filters and fuses are returned prepaid within 30 days Credit will be issued if not covered under warranty part is complete defective and returned on time Dealer Contractor Name Address City State Zip Ph 33 SECTION XI RECIRCULATION WARNING On Heaters which recirculate room air outside ventilation air must be provided in accordance with the information shown on the heater nameplate Recirculation of room air may be hazar
63. tee of the burner manifold or MR valve test port Slowly open all manual gas shut off valves Restart burner After pilot proven main gas valve opens and burner lights Adjust high gas pressure reading from manometer to match firing rate shown on unit nameplate first Refer to Maxitrol Valve Adjustment instructions in Section IX for setting high and low fire gas pres sure settings Adjust the high fire setting according to the Maxitrol Valve Adjustment instructions in Section IX The high fire setting must not exceed the pressure stated on the specification plate When adjusting low fire there should be a continuous flame along the entire burner length without any blowout spots Main burner flame sensor must be activated if applicable Check pilot and main gas lines for leaks Main flame is now set Make sure burner modulates and turn thermostat to the desired setting Cycle pilot and burner a number of times to insure smooth light off Check flame signal with burner cycling through full firing range and burner profile damper operation if applicable Unit Start Up Systems without Pilot Setting Burner NOTE To adjust gas pressure on supply lines where a regulator has been installed to reduce the inlet pressure to 1 2 PSIG or less remove dust cap of main gas regulator and turn adjusting screw clockwise to increase pressure or counter clock wise to decrease pressure Set all thermostats to call for heat
64. tion base 3 Check all wiring for loose connections and tighten if necessary 4 Inspect all fan and motor bearings and lubricate if necessary CAUTION DO NOT RUPTURE GREASE SEALS 5 Inspect pulleys and belts for tightness tension and alignment Do not overtighten belts 6 Check set screws on all bearings pulleys and fans for tightness 7 Check voltage supplied to disconnect switch the maximum voltage variation should not exceed 10 Phase voltage unbalance must not exceed 2 8 Check thermostat s for normal operation 9 Check that system duct work is installed and free from obstructions 10 Check that fans turn free in housing 11 Check burner for proper location and alignment 12 Check that filters and accessories are installed correctly 13 Check that vent lines have been run to atmosphere on indoor units Note that some units will use vent limiters and vent lines are not required 14 Check that all manual gas shut off valves are closed 15 When failure or malfunction of this heater creates a hazard to other fuel burning equipment e g when the heater provides make up air to a boiler room the heater is to be interlocked to open inlet air dampers or other such devices 16 If inlet duct is attached to the heater a purge timer must be provided and set to purge 4 times the inlet duct volume Purge time in seconds 4x Lx Wx H x 60 SCFM L duct length in feet W duct width in feet H duc
65. ut occurs depending on how the Airflow Switch selectable jumper JR3 is configured Ignition Trials 1 Pilot Flame Establishing Period PFEP a When the PFEP begins 1 The pilot valve and ignition transformer terminals 8 and 10 are energized The RM7895A B EC7895A and RM7896A B have an intermittent pilot valve terminal 8 The EC7895C RM7895C D RM7896C D have an interrupted pilot valve terminal 8 2 Flame must be proven by the end of the ten second PFEP four seconds if Configuration Jumper JR1 is clipped to allow the sequence to continue If a flame is not proven by the end of PFEP a safety shut down occurs b With flame proven the ignition terminal 10 is de energized 2 Main Flame Establishing Period MFEP a After Ignition Trials and with the presence of flame the main fuel valve terminal 9 is pow ered If a flameout occurs the relay module locks out or recycles depending on status of jumper JR2 within 0 8 or 3 seconds depending on the Flame Failure Response Time FFRT of the amplifier The RM7895C D EC7895C and RM7896C D have a ten second MFEP After the Ignition Trials and with the presence of flame the main fuel valve terminal 9 is powered If a flameout occurs the relay module locks out within 0 8 or 3 seconds depending on the amplifier FFRT o Run 1 The RM7895C D EC7895C RM7896C D has a delayed main valve that is energized once the RUN period is entered 2 The
66. val 100 RPM Upto125 F Clean 6 months 500 RPM Upto150 F Clean 2 months 1000 RPM Upto210 F Clean 2 weeks 1500 RPM Over150 F Clean weekly Any Speed Upto 150 F Dirty 1 week to 1 month Any Speed Over 150 F Dirty daily to 1 week Any Speed Any Temp Very Dirty daily to 1 week Any Speed Any Temp Extreme daily to Conditions 1 week 3 Dampers Dampers should be inspected monthly for securely fastened linkages and smooth operation If dampers are binding or excessively noisy then lubrication may be required Place one drop of 20 wt machine oil on each blade bearing and linkage ball joint Do not over lubricate and wipe any excess from the area Be sure to note that dampers over 49 inches long have intermediate bearings which require lubrica tion C Air Filters All filter banks should be equipped with a manometer or differential pressure switch to indicate when the filters are dirty Filters should be replaced when the differential pressure across them reaches the manufacturer s recommended final value Dirty filter elements should be replaced with a clean element of the same type and size In addition Sterling not only suggests but insists that air filters be checked every 30 days and replaced with new filters throw away type or cleaned washable type as required Clean able filters should be given new application of filter coating after washing to maintain optimum filter performance The frequency of cleaning an
67. ve K Discharge Air 1 Override Temperature Check Override Temper Reset to correct Temperature setting is too low ature Selector of TD114 temperature too low when 2 Burner capacity may Check for high fire If on high fire control can T115 is be insufficient Maxitrol manifold pressure do no more Heater unable operative specified for heater to furnish additional heat to raise temperature L Automatic 1 Faulty automatic Read voltage across auto Replace automatic control Control Valve control valve valve terminals If 24V AC valve will not open valve is faulty despite full 2 Open wire to Read voltage across Correct wiring 2 09 TROUBLESHOOTING GUIDE Series 44 Room Temperature Control Reproduced with permission from Maxitrol Company Symptom Possible Cause Field Test Remedy A No Gas Flow 1 Valve improperly installed Arrow on side of valve should point in direction of gas flow Install properly B Continuous Low Fire Electronics OK 1 Open circuit in modulator coil 2 Plunger missing jammed or improperly installed 3 Ruptured main or balancing diaphragm Remove wires connected to amplifier terminals 6 amp 7 and measure resistance MR212 60 80 ohms M611 45 55 ohms Inspect plunger should be installed to operate freely in solenoid sleeve Disassemble valve for inspection of internal parts If proper resistance

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