Carrier 58MVC Error Code 22: Abnormal Flame-Proving Signal
What Does Code 22 Mean?
Status code 22 on the Carrier 58MVC indicates that the flame sensor is detecting a flame while the gas valve is de-energized. Under normal operation, no flame should be present when the gas valve is off. The furnace responds by running the inducer motor continuously to vent any gas until the fault clears.
This condition almost always points to a gas valve that is leaking or stuck in the open position, allowing gas to flow to the burners when it should not be. Because uncontrolled gas flow creates a risk of gas buildup and potential ignition hazard, this code is treated as a high-priority safety concern.
If you see this code, turn off the gas supply to the furnace and shut off power. Do not attempt to diagnose or repair the gas valve yourself. A licensed HVAC technician needs to inspect the gas valve, test it for internal leaks, and replace it if necessary. The inducer motor running continuously is the furnace's way of protecting you by venting gas, but the root cause must be addressed promptly.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Leaky gas valve | Common | ✗ Call a pro → |
| Stuck-open gas valve | Common | ✗ Call a pro → |
When to Call a Professional
Contact a licensed HVAC technician if:
- Immediately when this code appears — a leaking or stuck-open gas valve is a safety hazard that requires professional gas valve inspection and likely replacement
✓ Verified against manufacturer service manual — March 2026