Ground Fault Interruptor Circuit trips with grounded plugs?

Question

Suddenly my gfic in the garage, into which I have had a grounded fridge and an ungrounded safety light plugged for over a year, has started tripping any time a grounded plug is plugged in. I unplugged the fridge and plugged in a grounded extension cord - same problem. What gives?

Answer 1

It is not uncommon for GFIC receptors to act up especially in a garage, or other damp area. You may end up replacing it and see of that repairs the problem.

Answer 2

Well, I'm a bit systematic so I would try to elimnate problems first.

1) Try taking that extension cord and plug it into a totally different outlet on a different breaker.  Try it with the safety light only first and then add the fridge.  I'm going to assume it'll work which means there's no trouble with the appliance or the safety light.  Double check to see exactly what is on the same breaker as your fridge and the safety light.  If you didn't wire it yourself, you may have more items drawing from the same breaker as the fridge & safety light.

2) Take off the cover of the outlet and make sure the GFI isn't melted, brown/black in color or making contact with anything else metal in there.  Smell the outlet as well.  If it's burnt or melted, you'll smell a wierd plastic odor.

3) Make sure the wires are connected well and nothing else is touching the ground wire in there.

4) Before you start, obviously you'll want to switch the breaker off at this point.  If you have any "extra" outlets or GFI outlets, try swapping the current one out and see if that fixes it.  Plug in botht he fridge and the safety light.

I've used a GFI from a major home improvement store once and in about a year, it gave me problems.  I went to the local electrical contractor store and replaced it with a better GFI and I haven't had a problem in over 6 years.  It may be a quality issue.

Also, if someone plugged in other tools that may have overloaded or came close to overloading that GFI, it could have melted some plastic components inside.  That's also happened to me before in the bathroom.  I think hairdryers and moisture were to blame.  Mice, insects or nests could be to blame as well if they get into the garage or walls.

I think after all that and replacing the GFI (get a quality one), I would be money that it should work.  If not, then get in touch with an electrician.

Let me know how it goes.

Answer 3

Seems like a compromised ground circuit or a worn-out GFIC unit.

Swap out the GFIC with another and verify its functionality. Test the ground for possible errant voltage-like you can get when appliances short to their grounded chassis, energizing the ground along the whole circuit. If she still blows, methodically eliminate each switch, outlet or energized appliance by removing each in turn from the circuit. Once the cause of the fault is taken off the circuit, the interrupter won't trip.

Answer 4

The plug has probably gone bad. When I moved into my current home several years ago, I too had a GFI outlet in the garage that was connected to both my bathroom outlets in circuit. Every day ,even though nothing was plugged in to any of the outlets at the time, I would have to reset the circuit. Come to find out the GFI outlet in the garage had gone bad. Replacing that particular outlet fixed the problem. Good Luck!