Ruud U802VA050317MSA Error Code A014_F: Flame Present with Gas Valve Off
What Does Code A014_F Mean?
The Ruud U802VA's Bluetooth Communicating IFC watches for a burner flame using a flame-rectification sensor: when flame is present, a tiny electrical current flows through the flame to ground and the board reads it as "flame detected." During normal operation the board only expects to see that current while it is holding the gas valve relay energized. Code A014_F means the board detected flame current at a time when it had de-energized (commanded off) the gas valve — flame the control never asked for.
On this furnace there are two realistic explanations. The most serious is a gas valve that is stuck or leaking, so gas keeps feeding the burners and burning after the control tells the valve to close. The second is a fault in the flame-sensing path — a shorted or contaminated sensor, moisture, or a control-board circuit issue — that reports flame when none is actually there. The board cannot tell these two apart on its own, so it flags the worst case.
A014_F is the same underlying "flame present with gas valve off" event that the IFC also reports as A127_F, which is the UL safety-classification version of the identical condition. If flame keeps being detected, the control escalates to the A116_F one-hour flame-presence lockout, whose one-hour timer only begins once flame is no longer sensed. Because a stuck-open gas valve cannot be ruled out from the code alone, A014_F should be treated as a potential gas hazard rather than a nuisance sensor fault.
What You'll Notice
- The contractor app or IFC reports A014_F while the thermostat is satisfied or the furnace is supposed to be idle
- Burners appear to stay lit, or relight on their own, after the heat call has ended
- The furnace will not begin a normal heat cycle and behaves as if locked out
- A faint gas odor near the furnace in the more serious stuck-valve case
- The blower may keep running to purge heat even though no heat call is active
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Stuck or leaking gas valve | Most common | ✗ Call a pro → |
| Faulty flame sensor reading false positive | Common | ✗ Call a pro → |
How This Is Diagnosed
A technician first confirms whether real flame is actually present with the valve commanded off, or whether the board is reading a false flame signal. They typically observe the burners directly during a controlled cycle and check the flame-sensor microamp signal and its wiring for shorts, moisture, or grounding problems. If the sensing path checks out but flame genuinely persists, attention shifts to the gas valve itself: the technician verifies that the valve fully seats and does not pass gas when de-energized, and checks the gas-valve relay circuit on the IFC for the welded-relay condition that can also drive this fault. This is diagnostic work on the gas valve, sensing circuit, and control board and is informational only — it is not homeowner-serviceable.
When to Call a Professional
This code involves components that are not homeowner-serviceable, so have a licensed HVAC technician diagnose and repair it. Keep in mind:
- A014_F is present and the burners appear to stay lit after the thermostat is satisfied
- There is any smell of gas near the furnace, in which case leave immediately and call your gas company first
- The code returns after power is cycled, indicating the condition is still active
- The same event is also showing as A127_F or has progressed to an A116_F flame-presence lockout
Frequently Asked Questions
Is it safe to keep running the furnace with an A014_F code?
No. Because the code can mean the gas valve is not closing, shut off the manual gas supply valve to the furnace and leave it off until a technician has inspected it. Do not repeatedly reset the furnace to force a cycle.
Could this just be a bad flame sensor giving a false reading?
It can be, and that is a common finding, but the control cannot distinguish a false reading from a genuinely stuck gas valve. A technician has to rule out the stuck-valve hazard first before treating it as a sensor issue.
How is A014_F different from A127_F?
They describe the same undesired-flame condition on this board. A127_F is the UL safety-classification version of the event, while A014_F is the general fault indication. Either one means the furnace detected flame it did not command.
✓ Verified against manufacturer service manual — March 2026