HVACopediaGoodman · Furnace troubleshooting
Igniter fault or improper grounding
What is going on
Furnace is locked out on an igniter circuit error. Control sees a bad igniter circuit or a bad ground. Check wiring and ground first, then igniter, then board. Power off before you touch it.
Likely causes
- Problem with igniter circuit wiring
- Improperly connected igniter
- Shorted igniter
- Poor unit ground
- Igniter relay fault on the integrated control module
Check in this order
- Turn power off before repair
- Check and correct wiring from the control module to the igniter. Look at the plug for burnt pins
- Replace a shorted igniter with the correct part
- Check and correct the unit ground wiring. A loose ground gives odd igniter faults
- Check igniter output from the control and replace if needed
- Replace the control module with the correct part if the igniter relay has failed
- Handle the igniter by the base, never the element
Applies to: 34.5 in chassis gas furnaces
More furnace guides
- Airflow lower than demanded, furnace runs on low stage when high stage is expected
- Alternate combustion air opening (upflow or horizontal)
- Alternate vent/flue location (upflow or horizontal left)
- Annual inspection checklist
- Auxiliary limit control (location and purpose)
- Auxiliary limit switch open (blower compartment)
Take it to the job
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Source: Goodman GMVC96 Service and Troubleshooting, p. 61. Written in our own words; check the manual for your exact model.
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.