If you smell ammonia, the cooling unit has failed. In areas of high humidity, it's probably from rust (although metal fatigue from vibration on the road can also crack the tubing). I still like the gas type units because of few moving parts. When we lived in Florida, common practice was to leave the fridge running on 110v to keep the system warm and deter rust. They use very little electricity compared to the cost of replacing the cooling unit and there is really nothing to 'wear out' by doing that. Cheapest way is to have the cooling unit repaired, quickest is to hit a Camping World and have them install a new one. At least with Camping World there will be many places to go if the new one has a problem.
