Electrical Wiring in the Home/Ground fault circuit


I am a retired HVAC service technician with 40+ yrs experience, so I am not unfamiliar with electric/electronic circuits or troubleshooting.There are not many ground fault circuits in HVAC though. I recently purchased a newer 6 yr. old house. I have a ground fault circuit that trips randomly. I have to reset the ground fault duplex outlet in the garage near the breaker panel when it trips. Also in the circuit that I know of are the garage door opener, laundry room light and possibly some other lights/outlets. As I understand GFI circuits, they trip when there is a small difference between the hot and neutral wire amperage. This would seem to mean that I would have either an intermittent short to ground or a miswiring problem such as something in the circuit with a separately wired neutral that when it has a load along with another component in the circuit shows an imbalance between the hot and the neutral. Please advise me if my thinking is correct and the best possible way to approach troubleshooting this problem. Any help/direction would be greatly appreciated.

Thank you,



It doesn't take much to trip a GFI and there are numerous reasons why they trip. Utility fluctuations, lightning, certain combinations of "devices" can trip a GFI for no apparant reason, water or moisture, the neutral coming in contact with "ground" can do it.

Try this first as its easy to do. Isolate your garage door openers from the GFI on an extension cord plugged into a non GFI circuit and see if that helps. The code says ceiling outlets in a garage must be GFI protected. I don't agree with that because of the nusiance and safety factor, lets say its pouring rain out thunder and lightning, the GFI trips and now you can't get into your garage. Or its winter with ice and snow on the ground. This could be more hazardous to your health than plugging into your non GFI protected ceiling outlet which is unlikely in the first place because of where it is and you surly must have a reachable GFI protected outlet from the floor that would be much easier. The point is it used to be OK to have non GFI protected outlets in the ceiling for door openers, now its not, probably because of some unlikely isolated incident that took place some where. I'm all for safety but this is taking it too far in my humble opinion. Here's another extreme example. The code also says the outlet you plug your spare refrig or freezer into in the garage must be GFI protected. You go away for a week the GFI trips, you come home to a small fortune of ruined food not to mention the smell and clean up ahead of you. This is lunacy to me. I'm not telling people to violate the code I'm just saying what can happen and how I feel about it.

Interior lights in finished area's should not be on a GFI for safety reasons. A light suddenly going out besides being inconvenient could have hazardous consequences. There are exceptions of course but you don't want your laundry room light going out on a regualr basis because a GFI is tripping. If you can change that so much the better but try the door openers and see if that doesn't help the situation.

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Electrical Wiring in the Home

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Licensed Master Electrician (32 years) 6165B Contractor in Closter New Jersey with 40 years total experience in Residential - Commercial - Industrial work. Emergency Service - General trouble shooting and repair work - ONAN & GENERAC generator installation - Paddle fans - Kitchen & Bath exhaust fans - AC lines - Smoke detectors - Telephone lines - Cable TV lines - Computer network cabling - Exterior lighting - Recessed lighting - Security lighting - (200 - 150 - 100 amp service up grades) - Electric Heat - New circuits - New appliance hook ups - and more ! FREE ESTIMATES 201-358-1552 Fully Insured


Licensed contractor in Closter New Jersey.

"The Frank Williams School of Electrical Construction". My dear old boss is 100 ! and still going God Bless him. I started working for "Tenafly Electric" right out of high school at 19. He was tough but I learned more working for him in 8 and half years than most guys. We did mostly industrial work while doing some commercial and residential so I was fortunate to be exposed to all 3 areas of electrical construction. The guys I worked with were all good guys and I stay in touch with some of them still. Most of us went into our own buisness's which says something about the caliber of the guys I worked with. We had some interesting clients : Wella Corp. of shampoo fame, Farah Fawcett etc, I didn't buy shampoo for 10 years. It was a great place to work. Pan Am the former airline just before they went under, another great place to work, nice clean environment. C&C Metals, the largest button manufacturer in the US at that time, a not so clean environment but a very interesting place to work, lots of machine's cranking out buttons of all kinds but you had to be on your toes, it was a potentially dangerous place to be . All kinds of action going on around you.

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