Lennox G24M3/4-100 User Manual

Page 28
Repair Parts List
The following repair parts are available through independent Lennox dealers. When ordering parts, include the complete furnace model number listed on the
A.G.A. or C.G.A. rating plate  Example: G24M3-75. Refer to page 3 for parts identification.
CABINET PARTS BLOWER PARTS NOx turbulator (60 Hz. X units only)
Front access panel Blower wheel Hot Surface Ignitor
Blower access panel Motor Flame rollout switch (two)
Cabinet cap Blower housing cut-off plate Flame sensor
Cabinet bottom Motor capacitor Primary limit
Vent adapter HEATING PARTS Secondary limit (two)
ELECTRICAL PARTS Heat exchanger Pressure switch
Transformer Main burners Wire harness plug / cap
Control board (Hot Surface Ignition) Main burner orifices Flue box
Door interlock switch Gas manifold/Burner box assembly Combustion air blower
Gas valve Gaskets
Low gas pressure switch (propane only)
Ignition Control Board Diagnostic Codes
DIAGNOSTIC CODES
LED #1 LED #2
DESCRIPTION
SLOW FLASH
SLOW FLASH
SIMULTANEOUS
SLOW FLASH
SLOW FLASH
FAST FLASH
ON
ON
OFF
ON
OFF
ON
SLOW FLASH
SLOW FLASH
SLOW FLASH
FAST FLASH
Primary or secondary limit switch open.
Rollout switch open. OR: 9pin connector improperly attached.
Flame sensed without gas valve energized.
Pressure switch open or has opened 5 times during a single call for heat;
OR: Blocked inlet/exhaust vent; OR: Condensate line blocked;
OR: Pressure switch closed prior to activation of combustion air blower.
Power on -- Normal operation.
Also signaled during cooling and continuous fan.
Main power polarity reversed. Switch line and neutral.
Low flame signal. Measures below .7 microAmps. Replace flame sense rod.
Circuit board failure or control wired incorrectly.
Watchguard -- burners failed to ignite.
SIMULTANEOUS
SLOW FLASH
SIMULTANEOUS
FAST FLASH
SIMULTANEOUS
FAST FLASH
Normal operation - signaled when heating demand initiated at
thermostat.
ALTERNATING
SLOW FLASH
ALTERNATING
SLOW FLASH
ON OFF
OFF ON
ALTERNATING
FAST FLASH
ALTERNATING
FAST FLASH
Improper main ground or line voltage below 75 volts;
OR: Broken ignitor; OR: Open ignitor circuit.
NOTE - Slow flash equals 1 Hz (one flash per second). Fast flash equals 3 Hz (three flashes per second).
Minimum flame sense current = 0.15 microAmps.

Lennox G24M3/4-100 Specifications

General

Brand	Lennox
Model	G24M3/4-100
Category	Furnace
Language	English