[Richard and Rhonda]

Cool.

Well, that's just downright strange. You said you had voltage out of the breaker, right? But no voltage at the other end of the wire?

I think this next step would already confirm what you suspect. If you disconnect the wiring at the breaker, and disconnect the wiring at the A/C, you could temporarily tie the wiring together at the A/C and check the hot and neutral for continuity by ohming it.

I would do this before I started disassembling the coach to run new wire. If the symptoms are true, either there is a break in the wire, and the wire runs through a junction box and a wire nut has come loose.



Whoa, wait a minute. What tells the A/C to come on? When you said roof unit it threw me. I have basement air but had a similar problem. On mine the thermostat "talked" to a printed circuit board. The circuit board had a relay that "made" to send power to the compressor unit. That relay was not making, and therefore no power to the compressor unit. I confirmed this by direct wiring the in and out power wires that went through the relay. I bought a new relay and installed it on the board. Voila !! A/C

What tells the A/C to come on? Is it a switch on the unit itself, or a wall mounted thermostat? I am sorry I am not familiar with your setup.