No 12v at thermostat for ac unit???

dougrainer wrote:
If you have a wall tstat, you will have the standard multiple wires coming from the roof top unit down to the wall tstat. YES, on Jayco's they use the one HOT(12 volt pos) blue wire from the furnace to power the 12 volt side of the Roof AC system. There are NO 120 tstat wires. The ONLY 120 is the roof top 120 voltage to run the unit. ALL controls to operate the roof top unit are 12 volt. This link will show you the wiring for a RVP/Coleman. Just remember, there are 2 blue wires from the furnace. ONE has 12 volts. THAT wire will be connected to the RED wire up at the AC unit. Doug

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Thanks bud for your reply. This is where I’m at today. I ohmed the blue+ wire that is supposed to go to the red positive, there must be a cut or torn wire in the chase of the wall. My guess that all the wires run from the top down is they are looped so the wires do not pull down. My guess is someone with a screw ruined the red 12v power wire to thermostat. I ended up running belding cable and ran it right to the furnace. Now I’m getting the correct voltage at thermostat. I have a new thermostat coming in tomorrow. Previous owner cut all the wires short. I guess I will update later.