Evap icing up

[acdii]

Took a trip to Utah, Bryce Canton to be exact, and I noticed the thermostat blinking df code, then the compressor shuts off. I had the fan set to 3, but could hear the compressor kick on and off. When it does then water would pour out the unit on the roof. What is interesting is it only did it in Utah where humidity was low, in Nebraska where it is 85% humidity, it doesn't do that. I cleaned the air filter, thinking that was the issue, but it still did it. What could be causing it? Happens whether it was fully opened, or baffled to the roof vents.

Its on a Coleman 274BH, which after 3000 miles of travel has performed flawlessly, though I was concerned the refer had an issue, it wouldn't stay lit on propane, then RTFM and found that is normal over 5500'.

[azdryheat]

There's supposed to be an icing sensor to prevent icing. Might want to have it checked out.