One air conditioner went out on our old Pace Arrow a couple decades ago. The symptoms indicated it probably burned out from low campground voltage someplace we'd been. As the guys indicate above, pedestal voltage can vary more than people think. Owners new to the game and unfamiliar with the following basic concept are most vulnerable: in midsummer when the heat is on and the campgrounds are full, the voltage available to any one campsite is most likely going to be less than optimum. The more people that turn on their air conditioners, the worse the situation gets. You can park your lawn chair next to the pedestal and check the voltage every 10 minutes, or run out and check it everytime someone new rolls into the park and hooks up. Or you can have protection already in place monitoring things 24/7.
When an electric motor first starts up it requires far more current to get up to speed than it does after it's fully running; much like a car requiring more fuel to get its weight rolling off the stopline than after it's up to road speed. The air conditioner compressor motor especially fits that bill. If it only has 90 volts to work with rather than the 110-120 volts it's designed for, the motor has to work much harder to "get off the line" and up to speed. At 90 volts it may never get up to speed, but rather overheat trying to. This is the number 1 cause of AC failures. And its likely to happen to you if you don't have protection in place. Even then, nothing's perfect - stuff can happen.
Since we've owned our Monterey, we've had several instances where our power went out. It ultimately turns out it was our built-in power protection shutting everything down. At least once in Dillon, MT, it was in a relatively nice, new RV park... and our air conditioners weren't on. It was just a bad campground circuit, going out at midnight, and requiring the c.g. owner to get out of bed and reset. Even parked by the side of our house one day, in storage with nothing particular on electrically, I kept hearing a clicking on the roof. Turned out it was the automatic satellite dish going on and off; and we've never even used it. I couldn't get it to stop, so I knew something was haywire electrically. Feeling the 15 amp minimal cord going to the coach from the house, it was warm. For 27 years I've used 15 amp cords to my RVs in storage, and it's been fine as long as you understand their extremely minimal function. I could hear the power unit in the cord reel bay snapping on and off too. Immediately unplugging, I checked the cords and found the small cord and 15/30amp adapter had burn marks. Apparently the adapter was bad. The power protection was trying to do its job in response, and it worked, but there still was risk of fire at the adapter laying on the gravel next to the coach. I bought a 30 amp extension cord ($$) to resolve the issue and all is well.
The point is that you never know, so it's best to be protected not just from surges, but from the more likely bad circuit or low voltage situation. Unless you'd rather pay the $500+ for a new air conditioner instead of new built-in whole-coach power protection.
Joel
