That said, a flaky GFI and show good during testing and then fail under load. Change out the GFI to another one, or to a regular outlet, and see if the problem disappears.
Changing to a regular outlet leaves downstream outlets, "unprotected", but you know your coach and your electrical usage and don't overload them anyway.
The exception is something like a fireplace, and let me suggest that a GFI be installed on that outlet's box. If the appliance is suspect, then placing the GFI on only that box saves the rest of the coach from aggravation outages.
Using a GFCI for this purpose is not correct. It is designed to protect people from getting electrocuted if they come in contact with the hot wire and ground some how. The fireplace is still in question.
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Rick & Melissa Young & Dawson (RIP), 2011 Meridian 40U, FL XCL, ISL 380HP/DEF, Al 3000 MH, 2014 Honda CR-V, SMI AF1, Blue Ox TruCenter & tow equip.,EEZTire TPMS. Servants On Wheels Ever Ready. Best job we ever paid to do . (full time volunteers)
I didn't say it was correct; just practical for the purpose mentioned. What are the odds of touching both of those wires for the fun of it, and getting electrocuted by 110V is like a little dog nipping at you once. Sans a pacemaker, it isn't deadly.
That said, I agree that it isn't playing by the rules, just playing to win the game.
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Rick and Sandy
2003 American Eagle, 52K miles