4+2 Inducer motor fault

What the control is telling you

Inducer did not start within 20 seconds of a heat call, its RPM is out of range, or the RPM signal was lost for 5 seconds while running.

Applies to: ICP F9MAE / G9MAE modulating variable-speed condensing gas furnaces (060, 080, 100, 120 kBtu/h)

Likely causes

• Wrong vent sizing
• Failed inducer motor
• Restricted combustion air supply
• Improper inducer motor wiring

Test and repair steps

1. Check vent and combustion air piping for size and obstructions.
2. Check inducer motor wiring and connectors at the control.
3. Run component self-test (SW1-6) - inducer should run at medium speed.
4. Replace the inducer motor if it does not run or its speed signal is missing.

Models that show this code

6 models in ICP (F/G)9MAE Modulating Furnace

Other codes on the same units

• 3 Low pressure switch did not close or reopened
• 3+5 Gas valve fault (modulating valve)
• 4 Limit circuit fault
• 4+1 Blower motor fault
• 4+3 Low/medium pressure switch open while medium/high switch closed
• 5 Abnormal flame-proving signal
• 6 Ignition proving failure
• 6+1 Ignition lockout