I'm trying to do some repairs on a house on our ranch the previous owner wired himself, which should set off a bunch of alarm bells right there. In one room there is a window air conditioning unit that's marked as using 230v a/c. As I remember, 230v is only one leg of three phase service. Is this correct?

Anyway, the people who lease the ranch SAY the a/c unit was working up until recently. I checked the wall plug, which has one verticle power blade and one horizontal along with the round ground one, and I get 120v to ground on one blade and nothing to ground on the other. Between the flat blades I get nothing which tells me there's some kind of break in the line (a breaker somewhere or it's burned in two) which goes Lord knows where. I'd need an Ouigi board to ask the guy how he wired this as he passed away a couple of years ago and the walls are all recycled shiplap. I'm just glad the place hasn't burned to the ground yet.

The house has only 120v service to it that I can tell (the stove is wired for 220v). How this was working up until now I don't know unless it was just the internal fan that was blowing. Is there a way to use 120v, or 220v, on 230v system? That sounds crazy to me and the information panel on the a/c unit doesn't hint at a re-wiring option like I've seen on some A/C motors.

Thanks in advance for anyone's insight out there.