What It Means
System failed to prove flame during ignition trial.
Bryant Furnace
Bryant Furnace Error Code 34
Troubleshooting guide for the Bryant Furnace system fault 34.
Possible Causes
- Low gas supply pressure or faulty gas valve.
- Cracked, worn, or dirty ignitor.
- Dirty or improperly grounded flame sensor.
- Inadequate combustion air or poor flame carryover.
Not sure which one it is — or if it's none of these? Try ACLogics today.
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
New to this code? Click to see why this happens
Full Diagnosis
Ignition Proving Failure. Control retries three times before lockout #14. Check flame sense, ground continuity, gas supply, HSI, and flame carryover.
All Recorded Causes
Check gas pressure and burner operation. Inspect ignitor for cracks or carbon buildup. Clean or replace flame sensor. Verify proper gas valve operation and check for proper combustion air. Control retries 3 times before lockout 14.
Verify Before Replacing Parts
- Confirm the exact Bryant model family and furnaces context before acting on a generic code description.
- Walk the entire heating sequence in order instead of jumping straight to the reported code, watching for check gas pressure and burner operation.
- Verify each safety device and prove where the sequence stops under live operation, including whether inspect ignitor for cracks or carbon buildup.
- After the correction, run the system long enough to confirm the furnaces fault does not return under normal load.
Still unsure about this fault?
ACLogics walks you through Bryant Furnace diagnostics step-by-step — so you confirm the cause before swapping parts.
