I have a 11 year old Carrier 58mxa gas furnace. We had a brown out and then black out for about one week. I installed a generator, the furnace would not ignite (lockout, code 14). I waited to get power back, same problem.
The burners do not light at all, at start up, and goes into ignition lockout.
I've seen code 14 and 34. We hear and see it spool up, and the ignitor starts to glow for about 5 seconds, then it shuts off. Tries 2 more times, then it goes into lockout.
We reset it (turn circuit breaker off/on), and 20% of the time, we can get the burners to light and the works great, until the temperature reaches it's programmed setting, shuts off, but then won't turn back on again when the heat is needed again.
We assume it's not the flame sensor, as we're not getting any flame at all at the burners.
We've recently paid a contractor close to $1,000 dollars to diagnose and fix the problem. They said it was the gas valve and replaced it. I think I was scammed b/c if it was the gas valve it wouldn't run at all, correct? They claimed to check everything and said they cleaned it. This process with this contractor lasted about one week. To make matters worse, the contractor order the wrong gas valve and tried to install. When he turned on the system all you smelt was natural gas. He said the new gas valve was defective but as it turns out it was the wrong gas valve. Other issues involved made me feel that all they cared about was money, not fixing the problem.
Anyway, after the valve was installed the unit worked for about one day and then right back to the same issues.
Enough of my crying, I just want to fix the problem.
What could it be? Hot water heater works and so does dryer.
The ignitor lights and the nothing.
Any helpful instructions? Thanks!