HVACopediaLennox · Furnace troubleshooting
AM radio static during ignition
What is going on
If you hear AM radio static while the ignitor is energized on a Lennox G43UF, that is the ignitor doing its thing. The hot surface ignitor on these SureLight boards can put out some electrical noise that a nearby radio picks up. The Lennox chart for this problem has you call technical support, and it gives no field repair beyond that.
Likely causes
- Ignitor operation producing electrical noise
Check in this order
- Confirm the noise only happens while the ignitor is energized.
- Check the furnace still lights and runs normally, since the static alone is not a failure.
- Per the Lennox troubleshooting chart, call Lennox Technical Support for this symptom.
- Have the model number and the board part number ready when you call (32M88, 78M47 or 100973-01).
Applies to: G43UF-24B-045 through G43UF-60D-135 (SureLight boards 32M88, 78M47, 100973-01)
More furnace guides
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- EL296UHV: normal gas heat sequence (what should happen after a call for heat)
- EL296UHV: what the display and the diagnostic button are telling you
- Furnace will not run (no heat) - Lennox EL195UHNE
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Source: Lennox G43UF Unit Information Corp. 0416-L4, Troubleshooting Chart Problem 8 p.55. 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.