Bryant 340MAV Error Code 22: Abnormal Flame-Proving Signal
What Does Code 22 Mean?
Status code 22 on the Bryant 340MAV is an abnormal flame-proving signal fault. The integrated furnace control has detected that the flame sensor is proving a flame while the gas valve is de-energized and should be closed. When this fault is active, the inducer motor continues running to ventilate the heat exchanger until the fault is cleared.
The service documentation identifies a leaky gas valve as the cause. A leaky valve allows a small amount of gas to pass through its seat even when the valve is commanded off, sustaining a residual flame that the flame sensor detects. This is a mechanical wear issue in the valve itself.
Because this fault indicates gas is flowing when it should not be, it is a safety-relevant condition. Do not continue operating the furnace until a licensed HVAC technician has inspected and replaced the gas valve if it is found to be leaking.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Leaky gas valve | Most common | ✗ Call a pro → |
When to Call a Professional
Contact a licensed HVAC technician if:
- Contact a technician immediately — a leaky gas valve is a safety hazard that must be inspected before operating the furnace
- Do not attempt to operate the furnace until code 22 is diagnosed and the gas valve is verified to be sealing correctly
✓ Verified against manufacturer service manual — March 2026