Issues with Dometic Blizzard NXT

[maxj113]

At the time we picked up our fifth wheel, we noticed the AC wouldn't always kick on when the temp changed 2+ degrees over what it was set to. It would be climb over 10 degrees and my wife would notice it getting warm but still wouldn't kick on with temp differentials over 10 degrees to what it was set to. Cycling the power didn't help. The dealer we bought it from changed the thermostat thinking that would fix the issue but we're still having issues and I've gone back/forth with them on trying to diagnose it without much luck. It's very intermittent, some times it works, some times it doesn't. Some times it works in the day when the temps are high and some times it doesn't. Some times it works at night when the temps are low and some times it doesn't. I can't figure out the pattern.

Since we live in a hot/humid climate, the dealer recommended we turn the fan onto "high" all the time we're using it to prevent the sensor from freezing. This seemed to work for awhile and we could turn the fan onto "high" manually and it would kick on right away (and subsequently, the compressor would work if the fan was always on). Now, when we try to turn on the fan, the fan some times works and some times doesn't, how long before the point of which we turn it on, on the thermostat, to when it actually turns on varies from a few seconds to several minutes to an hour. Same with the compressor, turning it off/turning it back on from the thermostat or changing the temperature to a lower setting won't kick it back on. We also tried to hold both up/down buttons with the unit off per dealer recommendation with no luck.

I've owned other campers and haven't had an issue like this with a Dometic unit, I'm very frustrated! I've taken it back to two different dealers 4 times but they can't find any issues. Please help.

Note, the Dometic AC unit in our bedroom seems to work fine even when the Blizzard NXT main unit is acting up. It is a Brisk II model.

[newman_fulltime]

If you pay attention to the 12 volt side you will start notice the ac works right when no other draw is on and the battery is full.seen this before with a bad converter

[Chris_Bryant]

Are the dealers recommended by Dometic? Have you been there while they tested it, and did it misbehave?
I take it you full time in it, you might get a recommendation for a mobile tech from Dometic, so they can come when it is not working. If you take it in and everything works, it’s impossible to diagnose- often problems like this will be rf interference, which go away when in the shop.

And hate to say it, but a “real” AC tech wouldn’t have a clue, that’s why they call guys like me for these units.

[Flute_Man]

I would call a real AC tech.
JerryParr