On the covered Carrier gas furnace, 34 means flame was not sensed during the trial for ignition. The control repeats the ignition sequence 3 more times before going to lockout code 14. It can also mean the flame signal was lost during steady operation. First, note whether the burners light briefly and go out, or never light at all.
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0 of 2 completedWhat to do first
ReversibleNote whether the burners light briefly and go out, or never light at all.
Correct only the documented fault domain
ReversibleCarrier's flowchart checks the hot-surface igniter (it should glow orange-white by the end of its 15-second test), the wiring and 24 volts to the gas valve, whether the gas valve opens and the manual gas cocks are open, and the flame sensor, which is cleaned with fine sandpaper. It also lists inadequate flame carryover, low inlet gas pressure, a slow-opening gas valve and flame-sensor location as causes. Gas and flame-sensing work is technician work.
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What does 34 mean on a Carrier gas furnace?+
Flame was not sensed during the trial for ignition. The control repeats the ignition sequence 3 more times before going to lockout code 14. It can also mean the flame signal was lost during steady operation.