Imak - we had the same issue with our 19H when we first got it. I had to pop the cover off the thermostat and wiggle it around a bit. It eventually came free and worked fine after that. You must be careful as I can see where it would be very easy to break it off....that is nooooo good.
Welcome to RVing and welcome to JOF !!!
2015 Eagle HT 29.5BHDS
2014 Ram 2500 SLT Quad Cab 5.7 Hemi