I think my contractor may have covered up the GFCI behind the tile in a bathroom remodel several years ago. It has been fine all this time, but recently my wife was dying her hair and popped the circuit from an outlet in another bathroom in the same circuit. What can I do other than tear out the tile to reach the tripped outlet?
I would like to replace the GFCI to keep the circuit protected. Can I put a GFCI outlet in another outlet and bypass the tripped one?
No, you cannot! At least you cannot without opening up the wall.
If you can get at it from the other side that may be an option but having a "buried" box, outlet, or junction is not allowed.
Unfortunately, you have discovered why that is. You have a problem and you cannot get to the GFCI outlet to fix it.
You've got a handful of potential problems there!
In the bathroom where you suspect the buried outlet have a look around for other outlets. Is there any outlet visible near the vanity? NEC requires at least one so a builder generally installs only one. I forget the maximum distance.. two feet? If you do find an outlet nearby the probability of a second outlet buried behind the tile is lower.
If you remain convinced there's an outlet buried behind the tile then inspect from the other side of the wall. Drill a large hole (3/4" or so) and have a look inside. Or, cut out a larger section of drywall. If you find there is indeed an outlet buried there you could fix the situation in several ways. One is to carefully cut the tile and reveal the outlet bathroom-side where it belongs. Another is to remove the junction box, turn it around to be exposed through the non-bathroom side of the wall, and install an outlet there (or a blank cover plate).
There's some chance the tripped GFCI could be in an unexpected place. Newer construction often puts GFCI in a circuit breaker panel. Also carefully check all the other GFCI locations (bathrooms, laundry, garage, unfinished basement, outdoors) for normal outlets that are without power, as well as for GFCI outlets you'd forgotten about. It's less common (and a code violation, I believe) for a bathroom to be tied into a GFCI-protected kitchen circuit.
This is a job for a good borescope! I'm a total amateur, but not through the tile, but from somewhere else like above it. You can probably rent one from Home Depot, get one with a long enough head. The other thing you can do, is come at it from the back - The other side of the wall, is usually in a closet, or maybe from a non-tiled portion of the other bathroom's wall. Much easier to fix drywall.
