Amana Furnace 5 Flashes: Flame Sensed, No Call for Heat
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Amana furnace 5 flashes: what it means
Five flashes on the diagnostic LED of an Amana furnace control board means flame was sensed when there was no call for heat β the flame sensor is detecting a flame signal while the gas valve should be fully closed.
There are two documented reasons this happens:
- The gas valve is leaking through β allowing a small amount of gas to burn at the burners even when the valve is commanded off.
- A flame sensor or wiring fault β the board is receiving a false flame signal (shorted or misrouted sensor wiring, moisture, or a grounding problem) when no flame is actually present.
Because option 1 involves a gas valve that is not fully sealing, this code is rated pro-level. Do not ignore it. On most Goodman/Amana integrated controls, the board responds to this condition by running the inducer and the circulating blower to purge the furnace until the flame signal disappears β so the usual symptom is air moving with no heat. Details, including whether the control holds until power is cycled, vary by board revision; that is for the technician to confirm on site against the boardβs own documentation.
If you smell gas at any point, stop. Leave the house, and from outside call your gas utilityβs emergency line or 911 before doing anything else.
Amana furnace 5 flashes: common causes, ranked by probability
- False flame signal from the flame sensor or its wiring β the most common non-emergency cause. A shorted, pinched, or moisture-affected sensor wire, or a poor board connection, can make the board βseeβ flame that isnβt there.
- Flame sensor grounding / mounting fault β a sensor touching a grounded surface or a bad burner-ground path can produce a spurious signal.
- Control board fault β the flame-sensing circuit on the ignition control board itself is misreading input.
- Gas valve leaking through (mechanical failure) β the valve is not fully closing, letting gas reach the burners after the heat call ends. This is the serious case and is why the code is treated as pro-only.
A technician works these in order β cheapest and most likely first (sensor/wiring), then the board, and finally confirms or rules out the gas valve, which is the highest-consequence failure.
How to fix Amana furnace 5 flashes: safe checks first
Keep to these homeowner-safe steps only:
- Note what the furnace is actually doing. If the blower and inducer keep running with no heat coming from the registers, that matches the purge behavior this code triggers β tell the technician, it helps confirm the fault.
- Cycle the power once. Turn the furnace switch or breaker off, wait 30 seconds, and back on β one reset attempt. This is a test, not a repair: even if 5 flashes do not come back, still book service, because a valve that leaks through can seal on one cycle and leak on the next.
- Look at visible vents and registers. Make sure supply and return grilles arenβt blocked.
- Check the condensate line (high-efficiency models) for obvious clogs or standing water at the trap.
- Write down the model number from the exterior rating label so the technician can bring the right parts.
Do not open the cabinet or the burner compartment, touch the flame sensor, gas valve, wiring, or board, or reset the unit repeatedly. Anything involving flame sensing or the gas valve is a technician job β and a possible gas-valve leak is why.
How a technician will diagnose it
A qualified tech will typically:
- Read the flash code and stored history on the control board to confirm 5 flashes and check for related faults.
- Inspect the flame sensor and its wiring for damage, pinching, moisture, poor connections, or a compromised ground.
- Watch the flame-sense signal with a meter through a full cycle β confirming whether a flame signal is present with the valve commanded closed.
- Verify the gas valve fully closes at the end of the heat call, checking for gas passing through when it should be off. This is the critical safety test.
- Test the control boardβs flame-sensing circuit if the sensor and valve check out.
Sanity check on a quote: a good tech should be able to tell you whether the problem is a false signal (sensor/wiring/board) or an actual leaking gas valve β those are very different repairs and price points. Be wary of a valve replacement quoted without any confirmation that the valve is actually leaking through.
Symptom, cause and what to do
| Symptom | Likely cause | DIY action | Technician job |
|---|---|---|---|
| 5 flashes, no obvious gas smell | False flame signal from sensor/wiring | Cycle power once; book service either way | Inspect/repair flame sensor wiring, ground, connections |
| 5 flashes returns immediately after reset | Sensor grounding fault or board misread | Stop resetting; call a pro | Meter-test flame-sense circuit; repair ground or replace board |
| Faint gas smell near furnace, 5 flashes | Gas valve leaking through | Shut off, ventilate, call gas utility/911 | Verify and replace leaking gas valve |
| Blower and inducer run but no heat | Board purging until the flame signal clears | One reset; do not keep resetting | Diagnose flame-sense circuit and valve seal |
| Code appears after recent service | Disturbed or pinched sensor wiring | None | Re-inspect and correct wiring from prior work |
Amana furnace 5 flashes repair cost
Honest US ranges, parts and labor combined:
- Diagnostic / service call: $80 β $180
- Flame sensor replacement or wiring repair: $150 β $350
- Control (ignition) board replacement: $400 β $1,200
- Gas valve replacement (leaking-through valve): $400 β $600+
There is no legitimate $0 outcome for this code. A power cycle may make the flashing stop, but a gas valve that is not fully sealing can leak intermittently β the code can clear while the hazard is still there. Any 5-flash event warrants professional verification even if it does not immediately recur. The safe outcome is a technician confirming which of the two failure modes you actually have.
Related codes
- 1 flash β Amana Furnace Code 1 Flash: Ignition Lockout Fixes
- 2 flashes β Amana Furnace 2 Flashes: Pressure Switch Stuck Closed Fix
- 3 flashes β Amana Furnace 3 Flashes: Pressure Switch Stuck Open Fix
- 4 flashes β Amana Furnace 4 Flashes: Open High-Limit Switch Fix
Codes 1 and 5 both involve flame sensing, but they are opposites: 1 flash is the furnace failing to prove flame during a heat call (ignition lockout), while 5 flashes is flame sensed with no call for heat. Note that 1 flash means ignition lockout on the common Goodman/Amana integrated board set, but it has been used for other faults on some older boards β the same βvaries by board revisionβ caveat applies there as it does to 5 flashes, so let the technician confirm against the correct documentation for your board. Gas-supply and ignition problems belong to the ignition/flame-proving codes above, not to this one.
Frequently asked questions
Is 5 flashes on an Amana furnace dangerous?
It can be. It means flame is detected when the gas valve should be closed, which may indicate a valve leaking gas through. Treat it as a pro-only repair and shut the unit down if you smell gas.
Can I just reset my furnace to clear the 5-flash code?
You can cycle power once to see what the furnace does. But clearing the code is not the same as fixing it β a gas valve that leaks through can seal on one cycle and leak on the next, so a 5-flash event should be verified by a technician even if it does not come back. Do not repeatedly reset it.
Will the furnace still run with a 5-flash error?
On most Goodman/Amana integrated controls the documented response is to run the inducer and the circulating blower to purge the furnace until the flame signal goes away. So what you usually see is the blower and inducer running with no heat coming out, rather than a dead furnace. Exact behavior varies by board revision.
How much does it cost to fix an Amana 5-flash code?
A flame-sensor or wiring repair is often $150β$350. A control board replacement commonly runs $400β$1,200 installed. If the gas valve is leaking and must be replaced, expect roughly $400β$600 or more installed.