it is finally chilly enough to try the heaters in az, so i did for the first time since i got the coach. there are 3 LP heaters. one in the front, middle and bedroom. the front two work fine. the back one fan comes on, but no heat. it is under the drawers in the hallway/bedroom closet. i have never played with one of these. is there something easy i can try? i did not swap the thermostats, but could try that.