Originally Posted by Cheesehead
Herk, you may be correct. Even so, won't the gas burner come on?
The gas system is completely different than the AC heater system.
However the common thread is "water in the tank."
Without water in the tank, the over temp thermostat could pop. This prevents power from going to the control board.
Make SURE the tank is full and the valves are properly positioned.
Make sure the outside AC switch and the inside DC/Gas switches are OFF.
Open the outside cover and press BOTH overheat reset buttons.
If they reset; you should be "Good to Go."
If one or the other system does not work, check back for some other things to check.
The over heat reset is under the rubber circles.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
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