SOLVED: No power getting to the thermostat
SOLVED: It was a short somewhere between the blue wires at the furnace and the tstat. Refer to this post Hi All, 1997 Terry 30g RV with an Atwood 8531-III DCLP furnace and a Coleman 7300 air con...
Forum Discussion
From your pics, the Roof AC IS controlled from the Wall Tstat. The HOT blue (12 volt positive wire) exiting the furnace goes to the wall tstat and supplies 12 volt power to the wall tstat. The wall tstat then sends the appropriate 12 volt signal to the roof AC to turn on the Fan and or the Compressor. The wall tstat then also sends a 12 volt signal BACK to the furnace to that second blue wire to turn the furnace ON. So, Check all the wires at the tstat for 12 volts. THAT one wire should be from the furnace. IF NONE of those wires have 12 volts you have a disconnect(open) between the furnace and the wall tstat. Be advised, that some OEM's will install an inline fuse inside the wall behind the tstat, so make sure there is NO in line fuse stuck down in the wall. There will be enough wire slack to pull the wiring out if there is a fuse. Doug
