Goodman furnace 7 red flashes: External lockout — ignition retries exhausted
Seven red flashes means the furnace used all its ignition retries without proving flame and locked out. A retry is an attempt to light after a failure to light at all.
Applies to: Goodman GMEC96 and Amana AMEC96 two-stage gas furnaces with a three-colour diagnostic LED.
What it means
Goodman separates retries from recycles on this control, and this code covers retries specifically — attempts to establish flame that never succeeded. That distinction is useful. A retry lockout means the furnace never got a flame going, which points at gas supply, the igniter, or flame detection failing from the start. A recycle lockout, signalled by eight red flashes, means flame was established and then lost, which points at something destabilising a flame that did light. Knowing which one you have narrows the investigation considerably before anyone opens the furnace.
Most common causes
- No gas reaching the burners — a closed valve, an empty propane tank, or a supply interruption.
- A failed hot surface igniter.
- A flame sensor coated with oxide, so a real flame goes undetected from the first attempt.
- A flame sensor bent out of the flame path.
- The gas valve not opening.
- Poor grounding, which breaks the flame rectification circuit.
- Low manifold pressure, so no stable flame is established.
How to diagnose it
- Distinguish this from eight red flashes carefully. Retries and recycles point at different parts of the problem.
- Check whether other gas appliances work, which separates a supply problem from a furnace problem.
- Check the furnace's manual gas valve is open, and on propane that the tank has fuel.
- Watch a start attempt if the furnace has a sight glass. On a retry lockout the burners typically never light at all.
- Note whether the furnace produces heat occasionally, which would indicate a lockout being released on a timer.
How to fix it
- Restore the gas supply if that is the cause.
- Igniter replacement, flame sensor cleaning, and gas pressure testing are technician work.
- Do not reset repeatedly to force a run. Each reset delivers gas to a burner that may not light it.
- Tell the technician whether the burners light at all. That single observation splits the diagnosis in half.
Notes
The retry and recycle split is more informative than most furnace codes manage. It is worth reading the count carefully, because seven and eight point at genuinely different failures despite both being lockouts.
Related
All codes for this manufacturer
Goodman and Amana furnace fault codes — every code, with what differs between models.