We had that happen last year, except that after checking checking all outlets with a GFI tester (cheap at hardware stores), we found no outlet showing GFI problems, and turning breakers off one at a time we discovered that the A/C (even when not running) circuit was the culprit. It usually took a few minutes to trip the GFI. I never did find what the problem was, since it seems to have gone away, with no such problems this year.
It's certainly possible that water got in somewhere I couldn't find, and evaporated over the winter, but I don't know that to be a fact. I also don't recall it causing us problems with the 30 amp boxes in campgrounds, only with the GFI at home.
|