Updated 2026-06-25
Goodman Furnace 5 flashes: What It Means & How to Fix It
Compiled & reviewed by Nikolai Tsyrenov · Updated 2026-06-25 · confidence: high
What does Goodman furnace 5 flashes mean?
Flame sensed with no call for heat — the control sees flame when there shouldn't be any. Most often caused by Short to ground in the flame-sense circuit, or shorted flame-sensor wiring.
What Goodman furnace 5 flashes means
Flame sensed with no call for heat — the control sees flame when there shouldn't be any.
Common causes
- Short to ground in the flame-sense circuit, or shorted flame-sensor wiring
- Lingering/slow-extinguishing burner flame
- A slow-closing or leaking gas valve
- A control board misreading the flame signal
Homeowner-safe steps to try
- This indicates the control sees flame when it shouldn't — a potential gas-valve concern that isn't a homeowner repair
- Turn the thermostat OFF; if you see or smell evidence of gas, treat it as a gas emergency
- Do NOT open the burner area or touch the gas valve
When to call a licensed HVAC technician
If the basic checks below don't clear the code, the fault recurs, or anything involves the gas valve, burners, flame sensor or wiring, stop and book a licensed HVAC technician. Repairs to the combustion or gas system are not DIY.
⚠️ Safety first. Gas furnaces burn fuel and produce combustion gases. If you ever smell gas (a rotten-egg or sulfur odor), hear hissing, or your carbon-monoxide alarm sounds, do not touch light switches, thermostats, or the furnace — leave the home immediately and call your gas utility's emergency line or 911 from outside. Homeowners should limit themselves to simple, safe steps: setting the thermostat, checking and replacing the air filter, confirming the furnace switch and breaker are on, keeping supply registers and return grilles open, and clearing snow, ice, or debris from outdoor vent and intake terminations. Never bypass, jumper, or reset safety switches (limit, flame-rollout, or pressure switches), never open the gas valve or burner compartment, and never attempt combustion, electrical, or control-board repairs yourself. Error codes point toward a problem but are not a substitute for proper diagnosis — when in doubt, turn the system off and call a licensed HVAC technician. Keep working carbon-monoxide detectors on every level of your home.
When to call a pro: Call a licensed HVAC technician promptly — a slow-closing gas valve or shorted flame-sense circuit needs professional attention. If you smell gas, leave immediately and call your gas utility or 911 from outside.
Goodman furnace 5 flashes FAQ
What does Goodman furnace 5 flashes mean?
Flame sensed with no call for heat — the control sees flame when there shouldn't be any.
What causes Goodman furnace 5 flashes?
Common causes: Short to ground in the flame-sense circuit, or shorted flame-sensor wiring; Lingering/slow-extinguishing burner flame; A slow-closing or leaking gas valve; A control board misreading the flame signal.
Can I fix Goodman furnace 5 flashes myself?
You can safely try: This indicates the control sees flame when it shouldn't — a potential gas-valve concern that isn't a homeowner repair; Turn the thermostat OFF; if you see or smell evidence of gas, treat it as a gas emergency; Do NOT open the burner area or touch the gas valve. Call a licensed HVAC technician promptly — a slow-closing gas valve or shorted flame-sense circuit needs professional attention. If you smell gas, leave immediately and call your gas utility or 911 from outside.
Other Goodman furnace codes
Goodman 1 flashLockout due to too many ignition retries (3) —Goodman 2 flashesPressure-switch circuit is stuck closed at theGoodman 3 flashesPressure-switch circuit is open (did not closeGoodman 4 flashesPrimary limit circuit (high-limit switch) is oGoodman 6 flashesFlame-rollout switch is open — a safety shutdoGoodman 7 flashesLow flame signal — the flame-sense micro-amp sGoodman 8 flashesProblem with the igniter circuit.
Sources: hvacdirect.com · inspectapedia.com. General information for homeowners, not professional advice — confirm against your furnace's manual and a licensed technician.