Goodman Furnace 5 (red LED) error code
The control board detects a flame signal even though there is no call for heat and the gas valve should be closed. The furnace shuts down as a safety precaution.
Also shown as: 5 red flashes, five red flashes, fault code 5 red, flame sensed no call for heat
Last updated: September 30, 2026
What causes the 5 (red LED) error?
- Failed integrated control module
- Gas valve not fully closing
- Stray voltage on the flame-sensor circuit
How to fix Goodman 5 (red LED) — step by step
Work through these in order, from simplest and safest first. Stop as soon as the code clears.
- Turn the furnace off
Switch the furnace off at the service switch and leave it off. - Check for gas smell
If you smell gas, leave the home and call your gas utility or emergency services from outside.Safety warning: Do not use phones, light switches, or anything that could spark while you are inside near a suspected gas leak. - Call a licensed technician
This fault means the control module or gas valve needs professional testing and replacement.
When to call a technician
- Immediately — do not try to run the furnace with this code
- Any smell of gas, at any time
Frequently asked questions
Can this code clear on its own?
No. A flame signal with no call for heat points to a failed control board or a gas valve that is not closing — both need professional repair.
Should I shut the gas off?
If you smell gas, yes — use the manual shutoff valve and leave the area. Otherwise leave the furnace powered off and call a technician.
Sources
Every meaning and fix above was checked against official manufacturer documentation:
FixCode provides general troubleshooting information only — not professional repair advice. If you are unsure about any step, stop and call a qualified technician. Repairs done incorrectly can be dangerous and may void your warranty.