Start by trying on propane. It should show cooling in a couple hours.
Yes, they had problems with the relay to power the 120 volt element.
If you have a multi-meter, locate the wires coming from the stack for the 120 volt element. Disconnect 120 volt power by un-plugging the refer. Disconnect the wires going to the element. Set meter on resistance. measure the wires to the element. You should have resistance.
Next, plug the refer back in. set refer to AC, test the terminals where the element connects. you should have 120 volts.
Order an new Dinosaur Electronics circuit board.
Bud
USAF Retired
Pace Arrow
2003 Chev Ice Road Tracker