Bryant 355MAV Error Code 14: Ignition Lockout
What Does Code 14 Mean?
Status code 14 on the Bryant 355MAV is an ignition lockout. The furnace tried to light and prove a flame, failed the allowed number of times, and shut itself down as a safety measure. The control will automatically attempt to reset after 3 hours.
This lockout is the end result of repeated code 34 (Ignition Proving Failure) events. On each attempt the inducer starts, the hot surface igniter heats, and the gas valve opens; if the flame sensor does not confirm a stable flame, the board retries. After the retries are exhausted, it promotes the condition to this code 14 lockout so gas is not repeatedly introduced without ignition.
The most common cause is a failed hot surface igniter that no longer glows hot enough to reliably light the burners. A dirty or cracked flame sensor that cannot confirm the flame, or a gas supply problem such as a closed valve or low pressure, are also frequent causes. Because the likely fixes on this model involve the igniter, gas supply, or flame sensor circuit, this code is not a safe do-it-yourself repair and should be handled by a technician.
What You'll Notice
- The furnace tries to light several times, then goes silent and stops attempting
- You may hear the inducer and igniter cycle but never a sustained burner flame
- No heat is produced and the home temperature falls
- The status LED flashes code 14 (one short flash, four long flashes)
- After about 3 hours the furnace tries again, and may lock out once more if unresolved
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Failed hot surface igniter | Most common | ✗ Call a pro → |
| Dirty or cracked flame sensor | Common | ✗ Call a pro → |
| Gas supply issue (valve off, low pressure) | Common | ✗ Call a pro → |
How This Is Diagnosed
A technician works the ignition sequence in order. The hot surface igniter is checked to confirm it glows and draws the correct current, since a weak or open igniter is the most common cause. The flame sensor is inspected and cleaned or replaced, and its flame-sense microamp signal is measured to confirm it can actually prove the flame.
Gas delivery is then verified — that the manual and main gas valves are open and inlet pressure is adequate — because no fuel means no ignition. Wiring and grounding to the igniter, sensor, and gas valve are confirmed last. All of these steps involve gas or the flame-sense circuit, so they are performed by a qualified technician, not the homeowner.
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:
- Code 14 keeps recurring after the 3-hour auto-reset
- The igniter never glows red-hot during the ignition attempt
- The burners light briefly and then go out within seconds
- You smell gas near the furnace at any time
- The gas supply may be interrupted or the inlet pressure is low
Frequently Asked Questions
What is the difference between code 14 and code 34 on a Bryant 355MAV?
Code 34 is the active ignition proving failure that occurs on each attempt. After the retries are used up, the board escalates to code 14, a lockout. Same underlying problem — the furnace could not prove a flame.
Can I fix a code 14 ignition lockout myself?
This code is marked professional-only on the 355MAV because the likely causes — a failed igniter, a flame-sense circuit issue, or a gas supply problem — involve components that should be tested and replaced by a qualified technician.
How much does it cost to fix ignition lockout on this furnace?
It depends on whether the fix is a flame sensor, a hot surface igniter, or a gas-supply correction, and on local labor rates, so costs vary widely by region. A technician can quote after diagnosing which part failed.
Sources
✓ Verified against manufacturer service manual — March 2026