Page 1
2000 Lennox Industries Inc.
Dallas, Texas
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
INSTALLATION
INSTRUCTIONS
G24M Series
GAS FURNACE
SureLight Ignition System
504,197M
02/2000
Supersedes 503,981M
Table of Contents
G24M Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . .
G24M Parts Arrangement 3. . . . . . . . . . . . . . . . . . . .
G24M Gas Furnace 3. . . . . . . . . . . . . . . . . . . . . . . . .
Shipping and Packing List 3. . . . . . . . . . . . . . . . . . . .
Requirements 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Combustion, Dilution & Ventilation Air 5. . . . . . . . . .
Setting Equipment 8. . . . . . . . . . . . . . . . . . . . . . . . . .
Duct System 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Venting 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Piping 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Start-up 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Pressure Adjustment 25. . . . . . . . . . . . . . . . . . .
High Altitude Information 25. . . . . . . . . . . . . . . . . . . .
Other Unit Adjustments 25. . . . . . . . . . . . . . . . . . . . .
Service 27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Parts List 28. . . . . . . . . . . . . . . . . . . . . . . . . . .
Ignition Control Board Diagnostic Codes 28. . . . . .
Troubleshooting 29. . . . . . . . . . . . . . . . . . . . . . . . . . .
G24M Start-up & Performance Check List 32. . . . .
WHAT TO DO IF YOU SMELL GAS:
If the information in this manual is not
followed exactly, a fire or explosion
may result causing property damage,
personal injury or death.
WARNING
Do not store or use gasoline or oth
er flammable vapors and liquids in
the vicinity of this or any other ap
pliance.
Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.
Do not try to light any appliance.
Do not touch any electrical switch; do not
use any phone in your building.
Immediately call your gas supplier from a
neighbor's phone. Follow the gas suppli
er's instructions.
If you cannot reach your gas supplier, call
the fire department.
Extinguish any open flames.
Litho USA