GM tech - Which Thor product to you own (Not listed in your profile)?
To touch on this "Running all day to keep cool" and you said something is wrong with that? I donít think so. My RV was in the SUN for about 10 hours or so on the 4th of July. We were at the lake for 8 hours (well with about 2 hours of driving as well) and it was on my driveway for 2 + hours with the AC running the entire time to cool down and maintain temp. It doesnít take long now to suck out the heat (Not like before). I had the Thermostat set at 70 deg and interior temp ranged between 72 - 74 deg depending on where you were.
My RV WAS IN THE FULL SUN THE ENTIRE DAY. If I had shade im sure the AC unit would have gone off. I had NO reflective bubbles in ANY of my windows. I was testing to see how cool I could get this coach AND to make sure nothing froze up. If I put bubbles in the FRONT windshield Im sure that would have helped maintain temp.
I had NO curtains drawn in the cockpit at all (Only the dinette shade and bedroom shades where pulled down). This was part of my test - see how comfortable I can make it WITHOUT the hassle of bubbles AND to be able to look out at the lake and enjoy the sunshine and my surrounding.
Perhaps you have double pane windows or a better coach that is more insulated? Sounds like your goes off after a few hours? What is your thermostat set at? Plus your output temp is around 5 deg cooler than mine (40 vs 45) so that might have made a difference.
Before I did my mods I was at 82 deg (at best Ė no joke) inside, in full sun with all of the windows blocked off with Reflective bubbles and could not see out any windows (And my AC unit running the entire time). So Im very happy with my results.