Well you got all the techie electrical info on the how and why I'll just chime in with ALL what has happened to your coach. AND it won't be all apparent right away.
And the BIL? Give him a break.
I Paid and ELECTRICIAN to hook me up a shore station and he wired it wrong!!
I plugged in and heard a strange noise coming from the ac opened the door and in the coach was filled with smoke.
That all said.
AC would come on but when it shut off when it hit the temps set it would not come back on. Micro blew up, fridge would run but would not come back on when it hit the temp set.
The convertor was the culprit for all of the above. It appeared to be working but when I smelling sulfur I found it was frying the batteries. Opened it up and one capacitor was literally blown out from the surge. So fridge and ac was not getting the 12 volt it needed for the thermostats on both to come back on.
AND....pull your GFI's out and REPLACE them. Months later I smelled burning wires and traced it to the GFI wiring. The GFI's continued to work so I had no idea they were starting to smolder.
When the coach took the surge I hit reset and it did, so I thought all was well. Not. the surge heated up the wires inside and over time they were arching inside the wall.
NOTE: When the fridge and ac started acting up no one including 2 repair guys put two and two together that it might be the converter. They tested the converter and when it hit the specs it was supposed to be putting out they took the tester off. 3rd guy left the tester on and it spiked off the charts.
The average cost of a 220 improperly wired surge hit to a MH is around $3,000. I was lucky enough that my ac didn't go up in flames so if cost me less.:W
