AC problems

[joel]

Coleman 6759 mach 3 with heat. Heat only works with switch turned to low or high cool and then turning the t-stat to warm.
The element will not come on in the appropriate low heat setting. this unt is original to the trailor and otherwise works great.
ANY IDEAS Thanks

[overlander63]

Sounds like the PC board that controls the climate control is messed up, they seem to be famous (or infamous) for that. Maybe Andy from Inland RV could tell you how to check it, if you asked him real nice...
Terry

[Inland RV Center, In]

Joel.

Several things to check.

Bad selector switch.

Relay terminals stuck.

Crimped wires shorting together.

Something shorting terminals on the selector switch.

Easy fix?? Disconnect the heating element.

No heat, but fixes the problem.

Andy