Posted by: Dave H. on March 22, 2001 at 15:18:52

I had an unused 220 outlet that had once run a window mounted air conditioner. I knew it was still live because I used a tester and it registered 220 V.

After I had my main panel upgraded to 200 amps, the receptacle no longer tests the same. If I put one probe in either hot slot and the ground, I shows 110 V. But if I try both hot slots, I get no reading at all. Anyone know what happened? Thanks.

Answer:
Whoever wired the receptacle put hot wires from the same panel buss to both sides of the receptacle. One of the wires in the panel has to be transferred to the other hot buss. If the wires are connected to a 230 volt breaker instead of two 115v breakers, the problem may be solved.