Travel Trailer AC Weak ~ Heartland Wilderness ~ Any others?

Just as with the RV refrigerator that performs better if turned on well in advance of use, the A/C should be turned on when the temps are about 80 so that it can keep up. If there is high humidity and high ambient temp, the unit will take many hours before the RV is comfortable inside. As mentioned, the typical unit when performing optimally will only create a temp gradient of about 15-20 deg.