Honeywell Q674L User's Manual
Contents
1. ANTICIAPTOR RTD 1 FALL La EM HT COMPRESSOR ai LED RED MONITOR 4 AUX HT LED RTD 1 Estes oH np FAN RELAY CHANGEOVER VALVE A POWER SUPPLY PROVIDE o EM HT RELAY DISCONNECT MEANS AND se OVERLOAD PROTECTION AS REQUIRED V LACO CHP A CONNECT CHANGEOVER Y 5 RELAY FOR HEAT CHANGEOVER TO O FOR COMPRESSOR COOL CHANGEOVER mM CONTACTOR B M HEAT CHANGEOVER VALVE M1030A Fig 7 Internal schematic and typical wiring diagram for Y594R1300 T874R1475 Q674L1520 fixed anticipation POWER SUPPLY PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED COMPRESSOR THERMOSTAT SUBBASE SYSTEM COMPONENTS e E wa Z W3 RELAY oy NJ 1 COOL CHANGEOVER VALVE COMPRESSOR MONITOR Hi FAN RELAY FAN E ANTICIPATOR SWITCH UY AUTO ANTICIPATOR ON LJ 0 I 5 5 C ZN EM HT AUX HT RELAY LED RED t SYSTEM SWITCH Q E aux ur yu Cray LED GAN i a EM HT RELAY maT H2 HEAT Cea 1 9 1 ANTICIPATOR HG Nr 5 OFF AX near FALL ro LX CHANGEOVER COOL e VALVE O W1 RELAY i A A remove JUMPER WHEN W1 RELAY IS USED RELAY ZA FACTORYANSTALLED JUMPER O Ev M5067 Fig 8 Internal sche2. 8 HEAT FALL CHANGEOVER VALVE COMPRESSOR IN POWER SUPPLY PROVIDE DISCONNECT MEANS AND RELAY OVERLOAD PROTECTION AS REQUIRED M5068 Fig 10 Internal schematic and typical wiring diagram for Y594R1615 T874R1822 Q674L1710 TRADELINE intended for use in applications where W2 and E terminals are not jumpered 69 0392 9 6 T874R THERMOSTATS AND Q674L SUBBASES THERMOSTAT SUBBASE SYSTEM COMPONENTS Ei La HOT FAN SWITCH FAN RELAY A H1 C1 ANTICIPATOR pa 2 S Eve t 8 H RELAY G Ev EM HT RELAY C815A1039 THERMISTOR ota CHANGEOVER VALVE COOL Oe COMPRESSOR CONTACTOR A POWER SUPPLY PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED M3173A H2 ANTICIPATOR RESET HEATER Fig 11 Internal schematic and typical wiring diagram for Y594R1672 T874R1889 Q674L1736 and Y594R1698 T874R1905 Q674L1777 Exact replacement for York model nos 2TH11702324 and 6TH11702224 THERMOSTAT SUBBASE SYSTEM COMPONENTS L1 9 HOT L2 LED RED H1 C1 ANTICIPATOR AUX HT FAN SWITCH AUX HT AUX HT LED GRN RELAY amp EH FAN RELAY ANTICIPATOR SYSTEM SWITCH COOL CHANGEOVER VALVE EM HT RELAY COMPRESSOR CONTACTOR B RELAY A POWER SUPPLY PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRE
3. Q674L1777 for York model nos 2TH11702324 and 6TH11702224 Includes C815A1054 Outdoor Thermistor Y594R1706b T874R1913 EM HT Manual Cool TRADEL NE exact replacement Q674L1777 for York model no 2TH11702224 Y594R1763 T874R1954 Manual Requires C815A Outdoor Thermister 5 Q674L1827 for outdoor reset Fixed stage 1 heat anticipation No heat anticipation in stage 2 heat Auto fan in EM HT Replaces Y594R 1136 Y594R1797 T874R1988 AUX HT Manual Heat TRADELINE 12 Q674L1868 EM HT or Cool EM HT LED also shows compressor malfunction Premier White color b U S Registered Trademark C 997 Honeywell Inc All Rights Reserved 69 0392 9 opyright O 1 T874R THERMOSTATS AND Q674L SUBBASES OPERATION On a 2 heat thermostat the two stages of heat make sequentially as the temperature drops Make refers to the mercury switch initiating a call for heat or cool There is about 1 F 0 6 C between stages so the sec ond stage makes only when the first stage can not handle the load The 1 0 6 C is referred to as the interstage differential The light emitting diodes LED on the subbase light when something specific happens within the system When an LED lights refer to this list for the meaning EM HT Emergency heat is operating The compres sor has failed and the heat pump is not operating LED lights when system switch is placed in the EM HT position by the home
4. SYSTEM SWITCH Q Q EM HT C 4 N 6 OUTDOOR 2 THERMISTOR MiB ra OUTDOOR 0 COOL t F 4 FA THERMOSTAT 5 5 COOL COMPRESSOR CHANGEOVER A POWER SUPPLY PROVIDE DISCONNECT MEANS AND AE OVERLOAD PROTECTION AS REQUIRED M2970 A FIELD REMOVABLE JUMPER Fig 5 Internal schematic and typical wiring diagram for Y594R1763 T874R1954 Q674L1827 Replaces GE AY28X078 AY28X139 Trane Baystat 139 Baystat 239 and Baystat 240 and Honeywell Y594R1136 Thermostats THERMOSTAT SUBBASE SYSTEM COMPONENTS HOT L1 L2 H1 C1 ANTICIPATOR FALL a Hi Ci zx RTD2 FAN SWITCH AUTO Cra ON ANTICIPATOR 63 M AUX HT RTD 1 LED GREEN Nr 6 A p FALL t QD T amp EM HT SYSTEM SYSTEM LED RED MONITOR RD SWITCH ojo O FAN RELAY a La EM HT 4 8 EM HT COOL CHANGEOVER RELAY ey VALVE US 1 LACO CHP Ber Br COMPRESSOR i 8 CONTACTOR POWER SUPPLY PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED VAN AUXILIARY HEAT LED AVAILABLE ON SOME MODELS Fig 6 Internal schematic and typical wiring diagram for Y594R1243 T874R1152 Q674L 1207 69 0392 9 M5072A T874R THERMOSTATS AND Q674L SUBBASES THERMOSTAT SUBBASE SYSTEM COMPONENTS H1 C1
5. dropped or shifted due to mishandling If the setpoint lever and the thermometer reading do not agree 1 Remove the thermostat cover by pulling out from the bottom of cover until it clears the mounting slots 2 Setthe thermostat cover on a table near an accurate thermometer 3 Allow 10 or 15 minutes for cover thermometer to sense area temperature compare the readings Be careful not to touch thermometer or breathe on it If the readings the same replace cover and put the system into operation If the readings are different insert a small screw driver into the thermometer and turn it until the thermometers have the same reading See Fig 15 Replace thermostat cover and put the system into operation gt a o Radiant heat from hands offsets the thermometer reading After making each adjustment wait 10 or 15 minutes for the thermometer to stabilize before comparing 5 M5070 Fig 15 Thermometer calibration NOTE 69 0392 9 69 0392 9 10 11 69 0392 9 Honeywell Automation and Control Solutions Honeywell International Inc Honeywell Limited Honeywell Limit e 1985 Douglas Drive North 35 Dynamic Drive Golden Valley MN 55422 Scarborough Ontario M1V 4Z9 Printed in U S A on recycled paper containing at least 10 69 0392 9 G H Rev 10 97 post consumer paper fibers www honeywell com yourhome
6. hole to prevent drafts from affecting thermo stat operation 4 Do overtighten thermostat captive mounting screws because damage to subbase threads can result 5 Do not short across coil terminals on heating relay or gas valve This can burn out the thermostat heat anticipator 6 Neverinstall more than one wire per terminal unless factory supplied jumper with spade terminals is used IMPORTANT Thermostats are calibrated at the factory using subbase mounted at true level Inaccurate subbase leveling causes the actual temperature to deviate from the setpoint temperature Location Install the thermostat about 5 ft 1 5m above the floor in an area with good air circulation at average temperature Do not install the thermostat where it can be affected by drafts or dead spots behind doors and in corners hotor cold air from ducts radiant heat from sun or appliances concealed pipes and chimneys unheated uncooled areas such as an outside wall behind the thermostat Mounting The Subbase The thermostat subbase can be mounted on a vertical outlet box horizontal outlet box or directly on the wall 1 If you must mount the subbase on a vertical outlet box order Honeywell 193121A Adapter Assembly See Fig 1 The assembly includes an adapter ring two screws and a cover plate to cover marks on the wall Install the ring and cover plate on the vertical outlet box For a wall installation hold s
7. Adjustable heat anticipator scale Temperature Setting Move the setpoint lever to the desired comfort position One lever controls both heating and cooling Subbase Setting System switching positions control thermostat operation as follows OFF Heating and cooling systems are off If the fan switch is at the AUTO position the cooling fan is also off HEAT Heating system is controlled by the thermostat Cooling system is off COOL Cooling system is controlled by the thermostat Heating system is off EM HT Emergency heat relay is energized on call for heat Cooling system is off Compressor is de energized Fan switching positions control fan operation as follows ON Fan operates continuously AUTO Fan operates as controlled by the thermostat To switch positions use thumb and index finger to slide lever to desired position Stop switch lever in detent directly over the desired function indicator mark for proper circuit operation CHECKOUT Heating Move the system switch on the Q674 Subbase to HEAT Move the setpoint lever on the T874 Thermostat about 10 F 6 C above room temperature Both stages of heating and the fan should start Move the setpoint lever about 10 F 6 C below room temperature Heating and fan should shut off NOTE To prevent compressor short cycling some manufacturer equipment includes a minimum off timer to provide a five minute time delay before turning on the compressor after the th
8. D A TERMINAL LABELED C X ON SOME MODELS M3683A A W3 TERMINAL AVAILABLE ON SOME MODELS ONLY Fig 12 Internal schematic and typical wiring diagram for Y594R1797 T874R1988 Q674L1868 7 69 0392 9 T874R THERMOSTATS AND Q674L SUBBASES Mounting the Thermostat 1 Remove the thermostat cover by pulling the bottom edge of the cover away from the base until it snaps free from the cover clip NOTE The cover is hinged at the top and can be removed by pulling out at the bottom 2 Carefully remove and discard polystyrene packing insert that protects the mercury switches during shipment 3 Turn over the thermostat base and note the spring fingers that engage the subbase contacts Make sure the spring fingers are 7ofbent flat preventing proper electrical contact with the subbase 4 Note the two tabs on the top inside edge of the thermostat base The tabs fit into corresponding slots on the top of the subbase Mount the thermo stat on the subbase 5 Align the two captive mounting screws in the thermostat base with the posts on the subbase See Fig 13 Tighten both screws Do not overtighten screws or damage to subbase posts can result 6 Hang the upper edge of the thermostat cover on top of the thermostat base and swing cover downward until it engages with the cover clip THERMOSTAT MOUNTING SLOTS 2 THERMOSTAT MOUNTING POST 2 THERMOSTAT x CAPTIVE MOUNTING M3266 SCREWS 2 Fig 13 Mounting the
9. Honeywell T874R Thermostats and Q674L Subbases Installation Instructions for the Trained Service Technician TRADELINE INSTALLATION INSTRUCTIONS APPLICATION The T874R Thermostat and Q674L Subbase provide 24 to 30 Vac control of 2 stage heating and 1 stage cool ing heat pump systems with manual changeover Q674L Subbase provides EM HT HEAT OFF COOL system switching and AUTO ON fan switching See Table 1 for specific T874R Q674L combinations Table 1 Thermostat Subbase Specifications Thermostat Thermostat Subbase Subbase Model LED See Package Numbers Indication Changeover Comments Fig Y594R1243 T874R1152 Manual Cool TRADELINE adjustable stage 2 Q674L1207 heat anticipation Fixed anticipation in stage 1 Auto fan in EM HT Y594R1300 T874R1475 AUX HT Manual Heat TRADELINE fixed heat Q674L1520 EM HT 8 or Cool anticipation Auto fan in EM HT Y594R1425 T874R1616 Manual SUPER TRADELINES fixed heat Q674L1587 or C anticipation Factory installed jumper across W1 and Y1 Auto fan in EM HT 7 Y594R1615 T874R1822 Manual TRADEL NES fixed heat 10 Q674L1710 orC anticipation Auto fan in EM HT Y594R1664 T874R1871 EM HT Manual Cool TRADEL NEO exact replacement Q674L1736 for York model no 2TH11702224 Y594R1672 T874R1889 EM HT Manual Cool TRADEL NE exact replacement 11 Q674L1736 for York model nos 2TH11702324 and 6TH11702224 Y594R1698b T874R1905 EM HT Manual Cool TRADELINE exact replacement 11
10. ctions when available To wire subbase proceed as follows 1 Connect the system wires to the subbase See Fig 5 12 A letter code for identification is located near each terminal The terminal barrier permits straight or conventional wraparound wiring connection See Fig 4 Firmly tighten each terminal screw Fit wires as close as possible to the subbase Push excess wire back into the hole 4 Plug the hole with nonflammable insulation to prevent drafts from affecting the thermostat WIRING THERMOSTAT MOUNTING TERMINAL CABLE OPENING SPIRIT LEVEL HOLES 2 C Ie E ale D ed Ca cay ojo a Ed Ca ra Da cd O6 DO MOUNTING POST 2 FOR LTO SPRING FINGER HOLES 2 MOUNTING CONTACTS ON THE THERMOSTAT THERMOSTAT UP TO 12 M927 Fig 3 Subbase components and leveling procedure FOR STRAIGHT INSERTION STRIP 5 16 IN 8 MM FOR WRAPAROUND STRIP 7 16 IN 11 MM aner 7 SUBBASE TERMINAL SCREW M928 Fig 4 Wiring connections 69 0392 9 T874R THERMOSTATS AND Q674L SUBBASES THERMOSTAT SUBBASE SYSTEM COMPONENTS FAN RELAY D O 1 Le AUX HT 2 A AU HEATER AUTO LED GREEN mn ON FAL e FALE FAN EM HT WI COMPRESSOR SWITCH LED RED MONITOR 2 L1 Q Da HOT L2 JN HS
11. ermostat last turned off the compressor or after the system first received power This delay protects the compressor Cooling N CAUTION Do not operate cooling if the outdoor temperature is below 50 F 10 C Refer to manufacturer recommendations Move the system switch on the Q674 Subbase to COOL Move the setpoint lever on the T874 Thermostat about 10 F 6 C below room temperature Cooling and fan should start see NOTE above Move the setpoint lever about 10 F 6 C above room temperature Cooling and fan should stop Emergency Heat Move the system switch to EM HT The EM HT LED should come on Move the setpoint lever about 10 F 6 C above room temperature The electric strip heater s should come on Move the setpoint lever about 10 F 6 C below room temperature The electric strip heater should de energize The EM HT LED remains on until system switch is moved to another position Fan Move the subbase system switch to OFF and the fan Switch to ON The fan should run continuously When the fan switch is in the AUTO position fan operation is con trolled by the heating or cooling system T874R THERMOSTATS AND Q674L SUBBASES CALIBRATION Thermostat T874 Thermostats are accurately calibrated at the factory There is no provision for feld calibration Thermometer The thermometer in the thermostat has been accurately calibrated at the factory The thermometer should need adjustment only if it was
12. matic and typical wiring diagram for Y594R1425 T874R1616 Q674L1587 SUPER TRADELINE universal model for heat cool or first stage heating changeover systems CHECK LED has isolated terminals for use in all systems 5 69 0392 9 T874R THERMOSTATS AND Q674L SUBBASES THERMOSTAT SUBBASE SYSTEM COMPONENTS Lt 12 gt HOT FAN SWITCH H1 C1 Too 9 FAN RELAY A ANTICIPATOR AUTO Ba e E ON _F 4_ O a AUX HT RELAY 8 H RELAY ANTICIPATOR svsrEM Q EJ RELAY O C815A1039 5 fev THERMISTOR o CHANGEOVER VALVE COOL RESET HEATER v 2 COMPRESSOR CONTACTOR A POWER SUPPLY PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED M3173A Fig 9 Internal schematic and typical wiring diagram for Y594R1664 T874R1871 Q674L1736 and Y594R1706 T874R1913 0674L1777 Exact replacement for York model no 2TH11702224 THERMOSTAT SUBBASE SYSTEM COMPONENTS W3 RELAY i o CHANGEOVER VALVE ANTICIPATOR CHECK EN LED RED COMPRESSOR c MONITOR C ANTICIPATOR SWITCH E AUTO A on CHG o 9 L2 SYSTEM Ele AUX HT RELAY SWITCH Q Q LED x s _ ere AHA AUX HT HT E LED EM HT RELAY OHH AH GREEN ANTICIPATOR See o Arco L Lnd
13. owner AUX HT Auxiliary heat is operating which means the weather is so cold that the heat pump cannot handle the load CHECK System needs to be checked See heating sys tem instructions for specific meaning NOTE LEDs are not field replaceable or addable RECYCLING NOTICE This control contains mercury in a sealed tube Do nof place control in the trash at the end of its useful life If this control is replacing a control that contains mer cury in a sealed tube do your old control in the trash Contact your local waste management authority for instructions regarding recycling and the proper disposal of this control or of an old control containing mercury in a sealed tube INSTALLATION When Installing this Product 1 Read these instructions carefully Failure to follow them could damage the product or cause a hazard ous condition 2 Check the ratings given in the instructions and on the product to make sure the product is suitable for your application 3 Installer must be a trained experienced service technician 4 After installation is complete check out product operation as provided in these instructions 69 0392 9 A CAUTION Disconnect power supply to prevent electrical shock or equipment damage 2 To prevent interference with the thermostat linkage keep wire length to a minimum and run wires as close as possible to the subbase 3 Push excess wire back into the hole and plug
14. rmostat on subbase SETTINGS N CAUTION On systems using a gas valve never apply a jumper across the valve coil terminals even temporarily This can burn out the thermostat heat anticipator s Heat Anticipator Setting 2nd Stage Y594R1243 Set the heat anticipator scale to match the primary control current draw When using a T874 Thermostat with two stages of heating set the heat anticipator to match the respective primary control current draw If the primary control nameplate has no rating or if further adjustment is necessary use the following procedure to determine the current draw Measure the current draw with the thermo stat removed and the power on 69 0392 9 1 Connect an ac ammeter of appropriate range between the heating terminals of the subbase Stage 2 between W2 and R 2 Move the system switch to HEAT 3 After one minute read the ammeter and record the reading Stage 2 amperes 4 After mounting the thermostat set the adjustable heat anticipator to match the respective reading measured in step 3 If equipment cycles too fast set the anticipator to a higher current rating not more than one half division at a time and recheck cycle rate Most conventional 2 stage heating equipment is designed to operate at 3 cycles per hour per stage See Fig 14 Most heat pump systems should cycle 2 1 2 to 3 times per hour MOVE INDICATOR TO MATCH CURRENT RATING OF PRIMARY CONTROL M3684 Fig 14
15. ubbase in position and mark holes for anchors See Fig 2 Obtain wall anchors locally Be careful that the wires do not fall back into the wall opening Set aside subbase Drill two 3 16 in 5 mm holes and gently tap anchors into the holes until flush with the wall VERTICAL ADAPTER MOUNTING SCREWS 2 3 7 HORIZONTAL 2 OUTLET ZAS N MOUNTING BOX SCREWS 2 g L N SUBBASE A NOT INCLUDED WITH UNIT A ACCESSORY PARTS AVAILABLE 1931214 M925 Fig 1 Installation of subbase on outlet box WIRES THROUGH WALL OPENING ANCHORS MOUNTING 2 HOLES X bs MOUNTING M926 SUBBASE SCREWS 2 Fig 2 Installation of subbase on wall 2 Run wires to the thermostat location 3 Pull wires through the cover plate if used and sub base cable opening See Fig 3 IMPORTANT Use 18 gauge color coded thermostat cable for proper wiring T874R THERMOSTATS AND Q674L SUBBASES 4 Secure the cover plate if used and subbase with the screws provided Do not fully tighten the subbase screws 5 Level the subbase by using a spirit level Firmly tighten subbase mounting screws See Fig 3 The subbase mounting holes provide for minor out of level adjustments IMPORTANT An incorrectly leveled subbase causes the temperature control to deviate from setpoint Wiring the Subbase All wiring must comply with local electrical codes and ordinances Follow equipment manufacturer wiring instru
Download Pdf Manuals
Related Search