Carrier furnace Status code 14: Ignition lockout
Code 14 means the furnace failed to prove ignition four times and locked out. It resets automatically after three hours, and the underlying cause is documented under code 34.
Applies to: Carrier 58MCB four-way multipoise condensing gas furnaces and related models using the same integrated furnace control. Bryant and Payne furnaces of the same generation use the same control and code set.
What it means
When the furnace tries to light and does not prove a flame, the control reports code 34 and tries again. Carrier's control allows three further attempts after the first failure, and when those are exhausted it locks out with code 14. The lockout clears automatically after three hours. That produces a distinctive symptom: the furnace appears to work occasionally, giving one burst of heat every few hours, which people often describe as the furnace being temperamental rather than broken. It is neither — it is locking out, waiting three hours, and failing again in exactly the same way.
Most common causes
- No gas reaching the burners — a closed valve, an empty propane tank, or a supply interruption.
- A failed hot surface igniter.
- A flame sensor coated with oxide, so a real flame goes undetected.
- Poor control ground continuity, which breaks flame detection.
- A flame sensor that is grounded when it should not be.
- A defective gas valve, or the manual shut-off closed.
- Low inlet gas pressure.
- Inadequate flame carryover between burners, or rough ignition.
How to diagnose it
- Read code 34's guidance as well, since Carrier's documentation refers this code there.
- Check whether other gas appliances work. If none do, the problem is the supply.
- Note the three-hour pattern, which confirms the lockout and retry behaviour.
- Watch a start attempt through the sight glass if the furnace has one. Whether the burners light at all separates an ignition problem from a flame-sensing problem.
- Check the furnace's manual gas valve is open.
How to fix it
- Restore the gas supply if that is the cause.
- Everything else here is technician work — igniter replacement, flame sensor cleaning, gas pressure testing, and grounding checks all sit in the ignition and gas circuits.
- Carrier's own documentation notes that the green and yellow ground wire must be connected to the furnace sheet metal, which is worth mentioning to a technician if the furnace has been worked on recently.
- Do not repeatedly reset the furnace to force it to run. Each attempt delivers gas to a burner that may not light it.
Notes
A furnace producing heat once every three hours is not struggling — it is locked out and being released on a timer. Recognising that pattern is the difference between calling for service now and calling during a cold snap.