Cert, you have a Norcold, right? You have probably checked your owners manual for directions on the operation of the controls.
So, and it's a long shot, but my fridge/micro/AC quit working recently on generator. The culprit was a loose ground wire in a junction box between the generator and the transfer switch.
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Darrell, Mary & K.C. Toller Mix
In our hearts: Goldens, Tess & Jericho
'15 Jayco Precept 31 UL "Bertha"
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Ready Brute Elite towbar and brake combo