Hi ,I'm new to this. I have an 02 Starcraft trailer. I had a new thermostat -Dometic single- and a new converter installed in '14. I used it a week. Then it sat till now. When it's hooked up to truck or battery or 110 the furnace stays on. I tried the thermostat but nothing. I called installer and he had me take fuse out ,but the fuse is for refrigerator too. When it's hot I shut off gas and furnace went off . Then it will come on again when gas is back on and won't shut off! Can I disconnect a wire ? Any ideas?