OK I was replacing a regular outlet in my bathroom with a GFCI outlet today with the electricity on. I know this is not smart but it was dark and I didn't want to work by flash light and my breaker box is not marked. I have done this plenty of other times, but here is the deal. I accidentally made a spark by hitting a common wire and hot wire together. When I went out to the breaker box a 40 amp fuse was tripped, which struck me as odd since it was only a 120 outlet. I after I flipped the breaker back to on I could no longer get any power to this outlet. This outlet has to be supplying another source somewhere because there are two sets of romex in the box. However I can not find anything else in the house that is linked to this outlet. I have no way to check our electric hotwater heater so I feel like it may be connected. I will find out in the morning I guess if the water is cold. If this is connected to the hot water eater and somehow converts to 240 after it leaves the 120 outlet can I still put a GFCI outlet or will it not allow this. Hopefully someone can make some sense of this and help me out I would really appreciate it.
Thanks again,

OK, you were replacing an outlet, you have two 2-wire cables in the outlet box. You created a short and trip the breaker. You went to the circuit panel and found a 40 amp breaker in the off position. You assumed that the 40 amp breaker was the tripped breaker. Resetting the breaker did not restore power to the outlet box. I assume that you checked both cables.

Did you check other breakers? Not all breakers move completely to the off position when tripped. Some move so little as to appear to still be in the on position. These breakers feel spongy when pressed toward the on position. To reset this type breaker, move to the off position then to the on position.

Is the 40 amp breaker a single breaker or a double breaker?


You are assuming that the 40 amp breaker supplies the water heater. This is unlikely unless the wiring was done by a totally incompetent person. Most residential water heater require 30 amp 240 volt power. That means a 30 double breaker and 10/2 cable.

It is more likely that the 40 amp breaker supplies a sub panel somewhere, a/c unit or small heating appliance. It could be unused. I would think 40 amps would be to small to supply a kitchen stove or cook top, but it could supply a small unit.

Suggest that you check all breakers by feel. If in doubt, turn it off and then back on. Assuming that you find the tripped breaker to the bathroom outlet, turn the 40 back to off, since you found it that way, until you are able to determine what it does.