Help us out here. What, exactly, does "fridge does not work any more" mean? Does it work on
propane, but not electricity? Or vice-versa? Can you get any cooling out of it? When you look in the back, is there any yellow powderish looking residue on the pipes? Is there a lingering ammonia smell?
All of those things will help give us an idea of what's wrong with it.
Also, remember that these are ammonia absorption refrigerators, not compressor-driven like you have at home. After starting, it will take from eight to twelve hours for them to cool adequately.
Please give us a little more info and we might be able to save you a ton of money.
Roger