Lennox G41UF?24B?045, Service Literature

Page 1: ...d in this manual is intended for use by qualified service technicians only All specifications are sub ject to change Procedures outlined in this manual are pre sented as a recommendation only and do n...

Page 2: ...x 17 5 8 x 28 5 8 102 x 448 x 727 4 x 21 5 8 x 28 5 8 102 x 549 x 727 Number and size of field provided filter in mm 16 x 25 x 1 406 x 635 x 25 20 x 25 x 1 508 x 635 x 25 Condensate Drain Heat 6 ft 1...

Page 3: ...x 24 x 1 in 610 x 610 x 25 mm Condensate Drain Heat 6 ft 1 8 m long 26K68 26K68 26K68 26K68 Drain Heat Cable 24 ft 7 3 m long 26K69 26K69 26K69 26K69 50 ft 15 2 m long 26K70 26K70 26K70 26K70 Heat Ca...

Page 4: ...ide return air applications G41UF 36B 070 PERFORMANCE External Static Air Volume Watts at Different Blower Speeds External Static Pressure High Medium High Medium Low Low in w g Pa cfm L s Watts cfm L...

Page 5: ...815 885 1640 775 720 1555 735 625 1340 630 510 NOTES All air data is measured external to unit without filter not furnished field provided G41UF 60C 090 PERFORMANCE Bottom Return Air Side Return Air w...

Page 6: ...660 1430 675 580 NOTES All air data is measured external to unit without filter not furnished field provided G41UF 60D 135 PERFORMANCE Single Side Return Air Air volumes in bold require field fabrica...

Page 7: ...AND MANIFOLD SIGHT GLASS DuralokPlusTM HEAT EXCHANGER ASSEMBLY CONDENSER COIL CONTROL BOX DOOR INTERLOCK SWITCH COLD HEADER COLLECTOR BOX COMBUSTION AIR INDUCER BLOWER ACCESS DOOR BURNER ACCESS PANEL...

Page 8: ...azard Disconnect power before servicing Control is not field repairable If control is inoperable sim ply replace entire control Can cause injury or death Unsafe operation will result if repair is atte...

Page 9: ...oes into Watchguard Flame Failure mode After a 60 min ute reset period the control will begin the ignition sequence again The SureLight control board has an added feature that pro longs the life of th...

Page 10: ...feature of the board voltage cannot be measured so ignitor must be ohmed Ohm value should be 10 9 to 19 7 FIGURE 6 13 32 5 8 SureLight Ignitor Location BURNERS FRONT VIEW MEASUREMENT IS TO I D OF RETE...

Page 11: ...ners failed to ignite SLOW FLASH OFF Flame sensed without gas valve energized ON SLOW FLASH Rollout switch open OR 12 pin connector improperly attached ON ON ON OFF Circuit board failure or control wi...

Page 12: ...CLAMSHELL Each Segment CONDENSER COIL WARM END HEADER BOX COLD END HEADER BOX COMBUSTION AIR INDUCER PROVE SWITCH TUBING PROVE SWITCH BURNER BOX ASSEMBLY LIMIT CONTROL SURELIGHT IGNITOR GAS VALVE ROL...

Page 13: ...up secondary limit control S113 is a N C auto reset switch located on the combustion air inducer See figure 9 for approximate location S113 acts as a backup to primary limit S10 in the event of an ind...

Page 14: ...G41UF units is factory preset to open at 280_F 12_F 138_C 6 7_C on a temperature rise All flame rollout switches are manually reset FIGURE 11 BURNER BOX ASSEMBLY FLAME ROLLOUT SWITCH S47 MANIFOLD GAS...

Page 15: ...l will not initiate ignition at start up FIGURE 13 COMBUSTION AIR PROVE SWITCH S18 PROVE SWITCH S18 PROVE SWITCH HOSE COLD END HEADER BOX ON OFF PROVE SWITCH BRACKET TAP TERMINALS TABLE 7 G41UF Unit S...

Page 16: ...not be used when inserting pipe 8 After assembly wipe excess cement from pipe at end of fitting socket A properly made joint will show a bead around its entire perimeter Any gaps may indi cate a defe...

Page 17: ...NG AND CONDENSATE TRAP INSTALLATION Right Hand Exit Shown CONDENSATE TRAP Must be installed on same side as exhaust piping VENT PLUG Must be glued in place PLUG FIGURE 18 PLUG TYPICAL G41UF 60D 135 VE...

Page 18: ...s and Propane appliances venting sizing tables in the cur rent standard of the CSA B149 1 Natural Gas and Propane Installation Code in Canada 9 After determining that each appliance remaining connecte...

Page 19: ...nimum for vent installations in Canada see current edition of CSA B149 Code E Clearance to non mechanical air supply inlet for vent installations in USA 12 in 305mm for vent installations in Canada 12...

Page 20: ...igure 16 Refer to figure 22 for proper piping method When exhaust piping must be run up an outside wall any reduction in exhaust pipe size must be done after the final elbow FIGURE 22 12 305 ABOVE AVE...

Page 21: ...t may be used on the condensate trap and line Heating cable kit is available from Lennox in various lengths 6 ft 1 8m kit no 18K48 24 ft 7 3m kit no 18K49 and 50 ft 15 2m kit no 18K50 CAUTION Do not u...

Page 22: ...s line 12 If the appliance will not operate follow the instructions Turning Off Gas to Unit and call your service techni cian or gas supplier Turning Off Gas to Unit 1 Set the thermostat to the lowest...

Page 23: ...TABLE 9 Conversion Kit and Prove Switch Requirements at Varying Altitudes Altitude Model Input Si Gas 0 4500 ft 0 1372 m 4 501 7500 ft 1373 2286 m 7501 10 000 ft 2286 3048 m p Size Required Prove Swi...

Page 24: ...c operation or underfire High pressure can result in permanent damage to gas valve or overfire For natural gas units operating pressure at unit gas connection must be between 4 5 W C and 13 0 W C For...

Page 25: ...9 48C 090 6 8 7 8 8 0 9 0 8 1 9 1 8 9 9 9 60C 090 6 8 7 8 7 6 8 6 7 9 8 9 8 5 9 5 48C 110 6 9 7 9 7 5 8 5 7 7 8 7 8 4 9 4 60C 110 6 8 7 8 7 2 8 2 8 0 9 0 8 8 9 8 60D 135 7 4 8 4 7 8 8 8 8 1 9 1 8 7 9...

Page 26: ...sted on the unit rating plate If the temperature is too low decrease blower speed If temperature is too high first check the firing rate Provided the firing rate is acceptable in crease blower speed t...

Page 27: ...umes which could contain carbon monoxide can be drawn into living space resulting in personal injury or death B Filters All G41UF filters are installed external to the unit Filters should be inspected...

Page 28: ...exchanger with soapy water solution or steam If steam is used it must be below 275 F 135 C 21 Thoroughly rinse and drain the heat exchanger Soap solutions can be corrosive Take care to rinse entire a...

Page 29: ...f the burners and crossovers for any block age caused by foreign matter Remove any blockage 7 Reconnect the sensor wire and reconnect the 2 pin plug to the ignitor wiring harness 8 Reinstall the burne...

Page 30: ...trol goes into 5 minute Watchguard Pressure Switch delay Once S18 closes a 15 second pre purge follows 4 SureLight control A92 energizes ignitor A 20 sec ond warm up period begins 5 Gas valve opens fo...

Page 31: ...VE OFF COMBUSTION AIR INDUCER ON INDOOR BLOWER ON HEATING SPEED LED 1 SLOW FLASH LED 2 OFF GAS VALVE OFF COMBUSTION AIR INDUCER OFF INDOOR BLOWER OFF WITH DELAY LED 1 OFF LED 2 SLOW FLASH Sequence hol...

Page 32: ...LAME FOR FIVE CONSECUTIVE TRIES DURING A SINGLE HEAT DEMAND WATCHGUARD MODE GAS VALVE OFF COMBUSTION AIR INDUCER OFF INDOOR BLOWER OFF WITH DELAY LEDs SIGNAL WATCHGUARD FAILURE CODE IS 60 MINUTE RESET...

Page 33: ...D SLOW FLASH RATE REMAINS UNCHANGED THROUGHOUT COOLING CYCLE THERMOSTAT CALLS FOR COOLING COMPRESSOR CONTACTOR AND SYSTEM FAN ENERGIZED WITH 0 SECOND DELAY COOLING SPEED EAC H TERM ENERGIZED COMPRESSO...

Page 34: ...ERMINAL IS ENERGIZED THERMOSTAT CALLS FOR HEAT W THERMOSTAT CALLS FOR COOLING THERMOSTAT OPENS SYSTEM FAN SWITCHED TO COOL H SPEED EAC H TERM REMAINS ON THERMOSTAT OPENS CONTROL G ENERGIZES SYSTEM FAN...

Page 35: ...h by pushing the top button ACTION 2 Determine the cause of the roll out switch activation before leaving furnace code LED 1 O 1 2 2 Roll out switch failure ACTION 1 Check continuity across roll out s...

Page 36: ...BLOWER DOES NOT ENERGIZE Condition Possible Cause Corrective Action Comments 2 1 Unit operates with a cooling or contin uous fan demand Combustion air inducer will not start with a Heating demand Diag...

Page 37: ...switch lines with a heating demand Diagnostic lights flash the pressure switch failure code 2 5 minutes after heating demand 3 1 2 Prove switch does not close due to obstructions in the pressure line...

Page 38: ...nt termination kit installed See Placement and Installation section Diagnostic lights flash the pressure switch code LED 1 Off 5 1 3 Condensate drain line is not draining properly ACTION 1 Check conde...

Page 39: ...sembly Condition will cause high CO2 with high CO ACTION 2 Seal leakage if possible replace heat exchanger if necessary tag and return heat exchanger to proper Lennox personnel 5 3 4 Insufficient flow...

Page 40: ...tion Comments 7 0 Indoor blower fails to operate in continuous fan cooling or heating mode 7 1 1 Miswiring of furnace or improper con nections at control or indoor blower motor ACTION 1 Correct wiring...