The GFCI outlet (A) by the vanity in my bathroom is not working. When I tried to push in the reset button, it would trip the breaker that controls the bathroom. I checked every single outlets in the house (including the ones outside and in the garage) and all of them works except the bad GFCI. The only other thing that may be connected to this GFCI (A) is the other GFCI (B) near the other vainity in the same bathroom. They are about a few feet away. I knew that because every time I flipped the break back on after pushing A's reset button, B's reset button is always depressed (was pressed before).

So I opened up the GFCI (A). Two lines are hooked to Load and two lines on Line. Ground is fine, not touching anything. When B is working (reset pushed in), both Load and Line of A have power. However, if I push test button of B and then test A again, Line has no power but Load still does. This is confusing, since I thought Line is the power source. If Line does not have power, Load should not have either.

Does this indicate GFCI A is broken? Should I replace it?

 

You may have line and load wires reversed on "A". The first thing I would do is disconnect the Load wires at GFCI "A" and test everything again. The second GFCI device ("B") SHOULD NOT be connected to the Load terminals of "A", but "B" could be a regular 15 amp duplex receptacle.

 

What is more strange is the Load of GFCI (A) still has power when I shut off the breaker that was tripped by pressing the reset button of A. What does that mean?This GFCI is controlled by a different breaker than everything else in the room including B?

 

It's hard to follow what you problem is but at the A GFI receptacle.... both black wires should be on the line side(brass screw) of the receptacle and both white wires should be on the line side(silver screw).

When wires in this way.... both GFI receptacles act and operate normally.

If you shut the power off to the A receptacle and you still have power.... you're going to need to find out where it's coming from. It almost sound like the two receptacles are fed from two different circuits.

 

A gfi fed from the panel does not kill power upstream. Tripping the test button kills any downstream power and the receptacle itself.

 

The fact that Load has power while Line does not after shut off the breaker can at least prove one thing, the lines are connected wrong, can it? Since Load is downstream, it should not have power in this case. Whoever installed this GFCI possibly flipped the lines for Load/Line. Does that make sense?

 

Definitely worth checking out.

 

Not at all.

If the breaker is turned off..... the circuit is DEAD. If the circuit is not dead then you have two different circuits feeding the same receptacles.

 

The buttons on the device are not a circuit breaker. Pressing the RESET button restores power to the LOAD terminals after the GFCI device has tripped.

 

I finally found the other circuit that is feeding this GFCI. I turned off the breaker and removed the GFCI from the lines. After I put the breaker back on, I tested everything again. Every outlet/appliance works except this odd looking outlet in the garage. I tested before and after GFCI was removed with voltage tester and result is the same, no power. Should I disable this outlet by taking it out? What kind of outlet is this?

 

I can't quite see the slot configuration due to the shadows in the picture, but it is a 20 amp twist lock receptacle. Probably used for some type of "heavy duty" tool in the garage.

 

When I said "breaker", I did mean the breaker in the circut box in the garage. For this GFCI, pushing reset button will trip the breaker and therefore shut off everything in the bathroom. Still in that case, LOAD of this GFCI has power and LINE does not. That's why I try to track down another circuit breaker that controls this GFCI and I found it.

I was under the impression though, that LINE is upstream (power source) and LOAD is downstream. LOAD should not have power when LINE is dead. I guess that is not the case for my issue.

 

Look again at post #2, apparently you never disconnected the wires from the LOAD side of "A". This should clear the fault causing both "A" and the breaker to trip. It is looking like you have 2 circuits feeding "A".

 

If you mean a non contact tester you have not yet actually tested for power. You can't reliably check for voltage with a non contact tester. You need an analog multimeter. If you don't have one a $8-$15 one is all you need.

 

I used two testers. One is a non contact. The other is like a flat screw driver at the end. You are supposed to stick it inside a socket or touch a wire to test. Neither of them show there is power.

 

I disconnected wires from both LOAD and LINE of A yesterday to see if there is anything not working after this GFCI removed from circuit. Are you suggesting I should reverse LOAD and LINE?

Indeed, two circuits feed A. One controls the bathroom where A is in, and the other controls the garage. That's why I went through all outlets in the garage last night and ended up finding the black outlet int the picture I posted.

 

Both are non contact testers and of no value for this kind of testing. They are more accurate to indicate no power but not enough to be sure. All tests must be made with an analog multimeter. Until that is done we really don't know what is going on.

 

Actually I have an analog multimeter at home. Just too lazy to use it is all. Anyway, I will test the outlet again tonight.

Alternatively, I can remove the outlet and test the exposed wires with my testers, right?

 

Please give the non contact testers to your kid to play with. Test black to white and black to ground using your multimeter.

 

Did you mean I test the wire behind the black outlet in the garage or "A"?

 

Remove each cable at A and test for voltage. Do the cables one at a time and reconnect before testing the next or label them and note their position so you can do all at once.

Remove the breaker panel cover and determine the connections for the twist lock receptacle. Post a clear picture of the connections.

 

Let me look at that suggestion again for a moment.

NO!! Where did you get that idea? This isn't rocket science, but your reading comprehension is a definite obstacle in your finding and fixing this problem.

 

My bad. So you are suggesting that I should disconnect the wires from LOAD of A, and keep wires from LINE connected? Is it hazardous to leave the wires that has power hanging behind the GFCI or should I do something, wrap the wire with tape?

 

Fixed it by disconnecting LOAD wires at A. Thanks a lot.

Did that with multimeter. It is 120 volt black to white and black to ground for both LOAD and LINE.

Since the problem is resolved by disconnecting LOAD wires, I did not bother to do this. I'll let this twist lock receptable remain a mystery.