Component self-test Run all furnace components for a short test

What the display is showing

Runs the inducer, igniter and blower speeds for a short time so you can see each part work. The gas valve and the humidifier terminal are not energized. It will not start with any thermostat signal present or while time delays are running. Holding the jumper longer than 2 seconds makes the LED flash code 10 and the request is ignored.

Applies to: (F/G)9MXE and (F/G)9MXT furnaces

What to do

1. Remove the blower door, disconnect the thermostat R lead at the control and hold the blower door switch closed.
2. Jumper terminal C to the TEST/TWIN quick-connect for about 2 seconds, until the LED goes off, then remove the jumper.
3. The LED repeats the previous status code 4 times, then the inducer starts.
4. 9MXT igniter on after 7 s for 15 s; blower runs LO-HT, HI-HT, COOL speed 10 s each; inducer drops to low for 10 s and stops.
5. 9MXE igniter on after 7 s for 15 s; blower runs continuous-fan, heat and cool speed 10 s each; inducer stops.
6. Reconnect R, restore the door, then confirm the furnace shuts down and restarts from the thermostat.

Settings for these units

• Filter size by casing width · KeepRite (F/G)96VTN Two-Stage Variable-Speed Furnace

Models that show this code

16 models in KeepRite (F/G)9MXE Single-Stage Furnace, KeepRite (F/G)9MXT Two-Stage Furnace

Other codes on the same units

• 7 Limit circuit lockout
• 8 Gas heating lockout - manual reset needed
• 9 High-heat pressure switch or relay did not close or reopened
• 10 Line voltage polarity reversed
• LED heartbeat Control OK - idle or running, no faults
• LED off Status LED dark - no power to the control or blown 3 A fuse
• LED steady ON Status LED on solid - control lockout (resets after 1 hour)
• Stored fault recall Read the last stored fault code from the control