ICP · Furnace

4+2 Inducer motor fault

High severity ICP (F/G)9MAE Modulating Furnace

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

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

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Source: ICP (F/G)9MAE Service and Technical Support Manual 440 04 4700 00, Figure 16 Troubleshooting Chart, p.35. Summarized in our own words; check the original manual for your model.

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For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.