No expert here, but your symptoms are telling me that it is overheating. Either a vent is clogged up or your limit switch is defective.
2013 Jayco Jayflight Swift 264BH
2002 Yukon 5.3L Vortex w/tow package
When I die, I want to go peacefully like my grandfather did–in his sleep. Not yelling and screaming like the passengers in his car.