COMFORT-AIRE Century GDD92C045B3M, Service Manual

Page 1: ...his is a safety alert symbol and should never be ignored When you see this symbol on labels or in manuals be alert to the potential for personal injury or death Electric shock hazard Can cause injury...

Page 2: ...3 3 M M A SINGLE STAGE PSC C SINGLE STAGE CONSTANT TORQUE T TWO STAGE VARIABLE SPEED ECM MODEL NUMBER GUIDE PHYSICAL AND ELECTRICAL DATA Model Input Btuh Output Btuh AFUE ICS Nominal Cooling Capacity...

Page 3: ...845 795 740 700 660 615 585 545 Low 695 640 575 530 485 445 390 335 GDD92C070B3M 1 2 10 x 8 40 70 High 1380 1345 1325 1295 1260 1235 1185 N A Med High 1265 1240 1215 1175 1135 1105 1080 1040 Med 1140...

Page 4: ...rn Air Base 68W62 17 5 B Width 68W63 21 0 C Width Night Service Kits 18F15 Single Stage Horizontal Suspension Kit 51W10 80 90 Kit Flush Mount Termination 90 Furnaces only US Only 51W11 2 3 Vent Versio...

Page 5: ...ssembly Gas Valve Heating Compartment Access Panel Blower Access Panel Cold End Header Box Control Box includes integrated control transformer and door switch Blower Assembly Bag Assemblies Cabinet Bl...

Page 6: ...the transformer T1 The breaker is rated at 3A at 32V If the current exceeds this limit the breaker will trip and all unit operation will shutdown The breaker can be manually reset by pressing the butt...

Page 7: ...heat demand 4 Low Flame Signal check flame sensor 5 Watchguard burner failed to light exceeded maximum number of retries or recycles 6 Not Used 7 Primary or Secondary Limit Open or Watchguard Mode Li...

Page 8: ...Open 9 Pressure Switch failed to close or opened during heat demand 10 Watchguard Pressure Switch opened 5 times during one heat demand 11 Pressure Switch stuck closed prior to activation of combustio...

Page 9: ...d has been satisfied can be adjusted by moving the jumper to a different setting The unit is shipped with a factory fan off setting of 90 seconds For customized comfort monitor the supply air temperat...

Page 10: ...to clean without removing any part of the burners During operation flame is sensed by current passed through the flame and sensing electrode The ignition control allows the gas valve to remain open as...

Page 11: ...sure safety shut off If the gas valve must be replaced the same type valve must be used 24VAC terminals and gas control switch are located on top of the valve All terminals on the gas valve are connec...

Page 12: ...Set Dial to DC MicroAmps Multi Meter To Control Sensor T erminal T o Flame Terminal Remove Sensor Wire from Intergrated Control and Connect Alligator Clip to Terminal on Control Flame Sensor Terminal...

Page 13: ...3 Check ignitor for correct voltage Insert meter probes into terminals 2 and 4 use small diameter probes in order not to damage plug Check voltage during 20 second ignitor warm up period Voltage shoul...

Page 14: ...monitors across the combustion air inducer orifice to insure proper flow through the heat exchanger The switch is a SPST N O pressure switch electrically connected to the integrated control The purpos...

Page 15: ...ne and with hose from the positive side of the manometer to the tee in the positive line NOTE tive However the port reads less negative pressure than the port 4 Operate unit and observe manometer read...

Page 16: ...through Table 11B Wrong pressure switch installed in the unit or pressure switch is out of calibration Check that the correct pressure switch is installed in the unit Replace pressure switch if neces...

Page 17: ...resent in tests 1 and 2 and motor is not operating properly replace motor The motor is not field repairable If replacing the indoor blower motor or blower wheel is necessary placement is critical The...

Page 18: ...P49 If 24 volts is not present problem may be up stream of plug P49 Proceed to test 4 Multi Meter set to VAC 12 0 12 0 24 Multi Meter set to VAC problem is with the harness If voltage is not present...

Page 19: ...20 000 2 K two kilo ohms two thousand ohms 0 2 000 200 two hundred ohms 0 200 Motor Module Installation All replacement motor control modules look similar however each module is designed for a specifi...

Page 20: ...PVC Low temperature solvent cement is recommended during cooler weather Metal or plastic strapping may be used for vent pipe hangers Uniformly apply a liberal coat of PVC primer for PVC or use a clean...

Page 21: ...cket Take care to keep excess cement out of socket Apply second coat to end of pipe 7 Immediately after applying last coat of cement to pipe and while both inside socket surface and end of pipe are we...

Page 22: ...ation home make provisions for draining condensate collection trap and lines Figure 20 CHIMNEY OR GAS VENT Check sizing for water heater only FURNACE Replaced by EL195 WATER HEATER OPENINGS To Adjacen...

Page 23: ...hs permitted Table 11A through Table 11B lists the maximum pipe lengths permitted Regardless of the diameter of pipe used the standard roof and wall terminations described in section Exhaust Piping Te...

Page 24: ...8 8 26 11 60 45 n a 92 92 73 9 21 n a 55 40 87 87 68 10 16 50 35 82 82 63 Concentric Termination Elevation 0 10 000 ft Number of 90 Elbows Used 1 1 2 Pipe 2 Pipe 2 1 2 Pipe 3 Pipe Model Model Model Mo...

Page 25: ...Capacity Capacity 045 070 090 045 070 090 045 070 090 045 070 090 1 15 10 n a 51 36 14 85 100 28 107 107 88 2 10 n a 46 31 9 80 95 23 102 102 83 3 n a 41 26 4 75 90 18 97 97 78 4 36 21 n a 70 85 13 9...

Page 26: ...ipe EXHAUST When transitioning up in pipe size use the shortest length of 2 PVC pipe possible When transitioning down in pipe size use at least 1 foot of 2 PVC pipe NOTE Exhaust pipe and intake pipe m...

Page 27: ...ake opening with the protective screen should always be directed forward or sideways 2 If intake air is drawn from a ventilated attic Figure 25 or ventilated crawlspace Figure 26 the exhaust vent leng...

Page 28: ...for details Position termination according to location given in Figure 28 or Figure 37 In addition position termination so it is free from any obstructions and 12 above the average snow accumulation...

Page 29: ...15 N A 3 in N A N A N A N A 10 10 1 Refer to 99 Minimum Design Temperature table provided in the current edition of the ASHRAE Fundamentals Handbook 2 Poly Propylene vent pipe PP by Duravent and Centr...

Page 30: ...52mm for appliances 10 000 pliances 10 000 Btuh 3kw and 50 000 pliances 50 000 Btuh 15kw 6 inches 152mm for appliances 10 000 Btuh 3kw 12 inches 305mm for appliances 10 000 Btuh 3kw and 100 000 Btuh 3...

Page 31: ...d terminate straight down using two 90 elbows see Figure 29 4 Exhaust piping must terminate straight out or up as shown A reducer may be required on the exhaust piping at the point where it exits the...

Page 32: ...ET METAL STRAP Clamp and sheet metal strap must be field installed to support the weight of the termination kit FLASHING Not Furnished CLAMP FIELD PROVIDED REDUCER MAY BE REQUIRED TO ADAPT LARGER VENT...

Page 33: ...ance under veranda porch deck or balcony 12 Equal to or greater than soffit depth 3 feet 9m 12 3 feet 9m within a height 15 feet 4 5m above the meter regulator assembly 3 feet 9m 6 inches 152mm for ap...

Page 34: ...xhaust pipe size must be done after the final elbow 4 Distance between exhaust pipe terminations on multiple furnaces must meet local codes Figure 38 Non Direct Vent Roof Termination Kit 15F75 or 44J4...

Page 35: ...nce above grade or average snow accumulation B Horizontal separation between intake and exhaust C Minimum from end of exhaust to inlet of intake D Exhaust pipe length E Wall support distance from top...

Page 36: ...n Figure 47 or Figure 48 Route the condensate line to an open drain Condensate line must maintain a 1 4 downward slope from the furnace to the drain 5 Figure 45 shows the furnace and evaporator coil u...

Page 37: ...ove condensate drain Figure 44 Condensate Trap with Optional Overflow Switch Figure 45 Unit with Cooling Coil Using Separate Drain Drain Field Provided Vent 1 min 2 max above condensate drain Condensa...

Page 38: ...2 inch PVC Pipe Not Furnished Drain Assembly for 3 4 inch Drain Pipe Condensate Drain Connection In Unit Condensate Drain Connection In Unit Vent To Drain Condensate Drain Connection In Unit Optional...

Page 39: ...1 2 inch PVC To Drain 90 Elbow 1 2 inch PVC Not Furnished 1 2 inch PVC Pipe Not Furnished Drain Assembly for 3 4 inch Drain Pipe 90 Street Elbow 1 2 inch PVC Not Furnished Condensate Drain Connection...

Page 40: ...heating demand 5 Wait for the combustion air inducer to stop Set the thermostat to initiate a heating demand and again allow the burners to fire for approximately 3 minutes 6 Adjust the thermostat to...

Page 41: ...gas piping threaded joints should be resistant to action of liquefied petroleum gases Testing Gas Piping In case emergency shutdown is required turn off the main shut off valve and disconnect the mai...

Page 42: ...ated on unit gas valve GV1 Checks of manifold pressure are made as verification of proper regulator adjustment 1 Connect the test gauge positive side to manifold pressure tap on gas valve 2 Tee into t...

Page 43: ...tion instruction for the conversion procedure Table 16 Supply Line and Manifold Pressure at All Altitudes inches w c for 1 Through 3 Units Capacity Gas Manifold Pressure in w g Supply Line Pressure in...

Page 44: ...in the voltage between Line Neutral and C as a function of load indicates a poor or partial ground Compare the readings to Table 20 If the readings exceed the maximum shown in Table 20 make repairs b...

Page 45: ...d return air plenums Insert manometer hose flush with inside edge of hole or insulation Seal around the hose with permagum Connect the zero end of the manometer to the discharge supply side of the sys...

Page 46: ...pressure drop than standard efficiency glass foam filters If the pressure drop is too great system capacity and performance may be reduced The pressure drop may also cause the limit to trip more freq...

Page 47: ...ure switch assembly 12 Disconnect the plug from the combustion air inducer Remove two screws which secure combustion air inducer to collector box Remove combustion air inducer assembly Remove ground w...

Page 48: ...g the Burner Assembly if needed 1 Turn off electrical and gas power supplies to furnace Remove upper and lower furnace access panels 2 Disconnect the 2 pin plug from the gas valve 3 Remove the burner...

Page 49: ...508134 01 Issue 2045 Page 49 of 53 Wiring Diagram...

Page 50: ...IZED GAS VALVE OFF COMBUSTION AIR INDUCER ON INDOOR BLOWER ON HEATING SPEED LED FLASHES CODE 11 PRESSURE SWITCH CLOSED GAS VALVE OFF COMBUSTION AIR INDUCER OFF INDOOR BLOWER OFF WITH DELAY Sequence ho...

Page 51: ...F WITH DELAY IS 60 MINUTE RESET PERIOD COMPLETE YES 4 SECONDS YES HAS CONTROL RESET IGNITION SEQUENCE FOUR TIMES FLAME SIGNAL 1 5 MICROAMPS OR GREATER YES YES YES ROLLOUT SWITCH CLOSED LED FLASHES COD...

Page 52: ...NITORED CONTINUOUSLY IS ROLLOUT SWITCH CLOSED LED SLOW FLASH RATE REMAINS UNCHANGED THROUGHOUT COOLING CYCLE THERMOSTAT CALLS FOR COOLING COMPRESSOR CONTACTOR AND SYSTEM FAN ENERGIZED WITH 2 SECOND DE...

Page 53: ...THERMOSTAT OPENS SYSTEM FAN SWITCHED TO COOL SPEED EAC TERM REMAINS ON THERMOSTAT OPENS MANUAL FAN SELECTION MADE AT THERMOSTAT CONTROL G ENERGIZES SYSTEM FAN AT FAN SPEED EAC TERM ENERGIZED NO YES Y...