My refrigerator works on ac only when gas bottles are off.
2017 micro lite 21fbrs.
It would be more helpful to post make and model number of fridge or supply pics of the control board.
Dan-Retired California Firefighter/EMT
and Zoe the Wonder Dog(R.I.P.)
2016 PrimeTime TracerAIR 255, pushing a 2014 Ford F150 SCREW XTR 4x4 3.5 Ecoboost w/Max Tow Package
4pt Equal-i-zer WDH and 1828lbs of payload capacity
USUALLY, if you have a fridge with an automatic setting, it will switch to ac when you plug in even with the propane bottles open. You MAY have a setting for electric only.
You probably need to lookup the refrigerator's manual for that refrigerator online if this is a new problem or a new rig to you.