Page 1: Table Of Contents
INSTALLATION £ INSTRUCTIONS 352'8&7 /,7(5$785( ¤ /HQQR[ ,QGXVWULHV ,QF 'DOODV 7H[DV *4 6(5,(6 81,76 GAS UNITS 503,893M 9/98 $:50780/08 503,225M /LWKR 86$ 7$%/( 2) &217(176 UNIT DIMENSIONS ....... . PARTS ARRANGEMENT .
Page 2: Unit Dimensions
*4 81,7 ',0(16,216,1&+(6 00 1-1/16 (27) 17-3/4 1-1/16 (451) (27) SUPPLY COMBUSTION OPENING INTAKE 26-1/8 Left Right 2-3/4 (70) GAS PIPING INLETS (both sides) ELECTRICAL INLETS (both sides) (51) AIR FLOW EXHAUST AIR OUTLETS (both sides) 15/16 (24) RETURN AIR (Either side or bottom) 15/16...
Page 3: Parts Arrangement
*4 3$576 $55$1*(0(17 HEAT EXCHANGER ASSEMBLY DIFFERENTIAL PRESSURE VESTIBULE PANEL SWITCH ORIFICE LIMIT CONTROL EXPANSION TANK GAS VALVE PVC AIR INTAKE SENSOR FITTING PRIMARY IGNITION CONTROL SPARK PLUG AIR INTAKE CHAMBER FLAPPER VALVE PURGE BLOWER CONTROL DOOR INTERLOCK SWITCH COVER BLOWER GASKET AIR FLAPPER...
Page 4: Typical Installation
*4 7<3,&$/ ,167$//$7,21 INTAKE PIPE 2” FLEXIBLE BOOT IN DUCT OR PLENUM (SUPPLY AIR) (51mm) PVC FLEXIBLE ISOLATION SUPPLY AIR HANGER RETURN MUFFLER** FLEXIBLE BOOT IN EXHAUST PIPE DUCT OR PLENUM 2”(51mm) PVC (RETURN AIR) SUPPLY AIR PLENUM MANUAL 1.5 TO 3 LB. (24 to 48 kg) DENSITY, MAIN SHUT OFF MATTE FACE, 1”...
Page 5: Requirements
If the Installation of Lennox gas central furnaces must con- damper is manually operated, it must be equipped to form with local building codes. In the absence of local...
Page 6: General
NOTE - - Units with Q4, Q4/5 and Q5 blowers use larger coil. Heating cable is available from Lennox in various opening. lengths: 6ft. (1.8m) - - kit no. 18K48; 24ft. (7.3m) - - kit no.
Page 7: Filter Assembly And Filters
Bottom Return Air Opening The access panel should be large enough to permit in- spection of heat exchanger for leaks after installation 1 - - Cut opening in floor or platform. (either by smoke or reflected light). The access panel 2 - - Flange return air plenum and lower into opening.
Page 8 7$%/( Each 90 elbow is equivalent to 5 feet (1.5m) of vent ' ),77,1*6 63(&,),&$7,216 3,3,1* $1 pipe. Two 45 elbows are equivalent to one 90 elbow. $670 3,3( ),77,1* 0$7(5,$/ 63(&,),&$7,21 One 45 elbow is equal to 2.5 feet (.76M) of vent pipe. If intake and exhaust piping runs are not equal in length 6FKHGXOH 39&...
Page 9 Heating cable kit is avail- (Must be left open.) (Factory Installed) able from Lennox in various lengths; 6ft. (1.8m) - - CONDENSATE kit no. 18K48; 24ft. (7.3m) - - kit no. 18K49; and 50ft. CONNECTION (15.2m) - - kit no.
Page 10 3 - - Suspend piping at a minimum of every 5 ft. D - - Removal of the Furnace from Common Vent (1.52m) using isolation hangers. A suitable hang- If a G21 furnace replaces a furnace which was commonly er can be fabricated by putting a sleeve of Arma- vented with another gas appliance, the size of the existing flex refrigeration piping insulation around the pipe vent pipe for that gas appliance must be checked.
Page 11 -ups. Heating cable installation kit is 1 - - Use PVC pipe for both intake and exhaust piping available from Lennox. See Exhaust and Condensate 2 - - Secure all joints, including drain leg, gas tight us- Piping section for part numbers.
Page 12 NOTE - - Care must be taken to avoid recirculation of exhaust back into intake pipe. 7 - - On field supplied terminations, the minimum sep- aration distance between the end of the exhaust pipe and the end of the intake pipe is 8” (203mm). 8 - - If intake and exhaust piping must be run up a side wall to position above snow accumulation or other obstructions.
Page 13 3 x 2 (76 x 51) OR Inches(mm) EXHAUST 1/2 (13) 2 x 1- -1/2 (51 x 38) TERMINATION FOAM REDUCER BUSHING LOCATION INSULATION EXHAUST FOR OFFSET TERMINATION 3 (76) OR 2 (51) 90 ELBOW INTAKE TERMINATION 12 (305) Min. INTAKE above grade.
Page 14: Gas Piping
G21 VENTING IN EXISTING CHIMNEY COVER EXHAUST Front View (305) VENT WITH 1/2 (13) FOAM INSULATION INTAKE 3” - - 8” (76mm- - 8” - - 12” EXHAUST 203mm) (203mm - - 305mm) 12 MIN. (127) (305) Above Grade 5-1/2 (140) GRADE 3”...
Page 15 TABLE 5 GAS PIPE CAPACITY - - FT /HR (kL/HR) Length of Pipe- -Feet(m) Nominal Nominal Internal Internal Iron Pipe Size Diameter - -Inches(mm) - -Inches(mm) (3.048) (6.096) (9.144) (12.192) (15.240) (18.288) (21.336) (24.384) (27.432) (30.480) .364 (6.35) (9.246) (1.13) (.82) (.68) (.57)
Page 16: Electrical
ELECTRICAL to the current National Electric Code ANSI/NFPA for the U.S.A. and current Canadian Electrical 1 - - Select circuit protection and wire size according to Code Part 1 for Canada. the unit rating plate. 7 - - Install an auxiliary receptacle near unit. 2 - - Access openings are provided on both sides of the G21 and CONDENSING UNIT furnace cabinet to facilitate wiring.
Page 17: Unit Start--Up
81,7 67$5783 ROBERTSHAW 7200 GAS VALVE FOR YOUR SAFETY READ BEFORE LIGHTING GAS VALVE SELECTOR ARM IN OFF WARNING POSITION Do not use this furnace if any part has been under water. Immediately call a qualified service techni- cian to inspect the furnace and to replace any part of the control system and any gas control which has been under water.
Page 18: Gas Pressure Adjustment
This type of nuisance lockout is usually attributed Propane/LP Gas Conversion to low gas line pressure. After one hour of continuous NOTE - - G21Q series units are NOT shipped with the thermostat demand for heat, the watchguard will break components required for field conversion to propane/ and remake thermostat demand to the furnace and auto- LP gas.
Page 19: Service
Filter handicoater is RP Products 12- - Disconnect the gas supply piping from the unit. coating no. 481 and is available as Lennox part no. P- -8- -5069. 13- - Disconnect the wiring to the gas valve. 3 - - If replacement is necessary, order Lennox part...
Page 20: Repair Parts
5(3$,5 3$576 /,67 The following repair parts are available through independent Lennox dealers. When ordering parts, include the complete furnace model number listed on the unit rating plate. Example: G21Q3- -60- -1.
Page 21 G21 TROUBLESHOOTING FLOW CHART (continued from flow chart on previous page) NOTE—Numbered steps refer to illustrations on next to last page. UNIT WILL NOT RUN ELECTRICAL IS THERMOSTAT PROPERLY SET? CHECKS SYSTEM MAY BE LOCKED OUT. TURN THERMOSTAT HEATING DEMAND SET FOR HEAT DEMAND OFF AND ON AGAIN.
Page 22 G21 TROUBLESHOOTING FLOW CHART (continued form flow chart on previous page) NOTE—Numbered steps refer to illustrations on next to last page. CONTINUED FORM CHECK FOR LEAKS IN UNIT MANIFOLD PIPING. UNIT WILL NOT RUN CHECKS FLOW CHART ON PREVIOUS PAGE IS GAS SUPPLY NATURAL OR L.P.? LEAKS NO LEAKS...
Page 23 G21 TROUBLESHOOTING FLOW CHART — UNIT WILL NOT RUN CHECK VOLTAGE AT TERMINAL AND CHECKING VOLTAGE AT PRIMARY CONTROL CHECKING THERMOSTAT DEMAND 24VAC? LOW VOLTAGE TERMINAL PRIMARY CONTROL THERMOSTAT STRIP WITH FUSE WIRING HARNESS PLUG (JP1) WIRING LOCATED ON CONTROL BOX 24VAC 24VAC POWER?
Page 24: Start--Up And Performance Check List
67$5783 $1' 3(5)250$1&( &+(&. /,67 -RE 1DPH -RE 1R 'DWH -RE /RFDWLRQ &LW\ 6WDWH ,QVWDOOHU &LW\ 6WDWH 7HFKQLFLDQ 8QLW 0RGHO 1R 6HULDO 1R +($7,1* 6(&7,21 (OHFWULFDO &RQQHFWLRQV 7LJKW" %ORZHU 0RWRU +3 6XSSO\ 9ROWDJH *DV 3LSLQJ &RQQHFWLRQV %ORZHU 0RWRU $PSV 7LJKW /HDN7HVWHG" %ORZHU 0RWRU /XEULFDWLRQ 2."...

This manual is also suitable for:

G21 q3-40 G21 q3-60 G21 q3-80 G21 q4-60 G21 q4-80 G21 q3-100 ... Show all

Lennox G21Q Series Installation Instructions Manual

Quick Links

Related Manuals for Lennox G21Q Series

Summary of Contents for Lennox G21Q Series

This manual is also suitable for:

Table of Contents