Over the past couple of years on Facebook and the Forum there have been posts about the Truma AC going from blowing cool air to warm, humid air. I don't remember if there was an adjustment that solved this issue.
An Owner on Facebook set-up camp, turned on the AC, and things started cooling. They left on a hike and upon return the unit was blowing hot air. Upon arrival to the campground the temperature was a sweltering 97°.
Looking for suggestions to help this person. I suggested she contact Truma first thing this morning. I did Google this and posted some trouble shooting ideas, and requested additional info and any updates. Unfortunately, she hasn't posted back. Thanks.