Originally Posted by leemandell
I'm in the process of fixing up a 1979 31' Sovereign
to use as an office. I'm hoping to use the existing AC circuits but have run into a problem when testing them. The general circuit and the air conditioner circuit run fine but when I apply power to the appliance circuit I'm getting just 15 volts AC at the outlets.
I'm completely stumped on this one and have no idea how the voltage is being stepped down like that. Any insight would be greatly appreciated.
Is this with a load applied (say, a 60W incandescent light bulb)? Does it vary with the applied load? What happens if you plug in an electric toaster?
I would measure the voltage from hot to neutral and hot to ground, both at the wall plug and at the breaker. Flip the breaker off and then back on and see if the voltage changes. If you have an IR thermometer or camera, aim it at the wall plug contacts and at the breaker (while the circuit is under load) to see if it's getting suspiciously warm.
What you might be looking for is a high resistance connection such as a loose screw or a corroded contact. In that case, the resistance will dissipate much more power than the rest of the circuit and it will get hot. The danger, of course, is that this could eventually melt something or cause a fire.
Our '74 had copper wire; but you should check that you don't have aluminum AC wiring. If you do, then it's possible that dissimilar metal corrosion is causing a poor connection somewhere and you need to clean and tighten those connections (but the preferred thing to do would be to rip out the aluminum wiring).