It’s not uncommon for Ground Fault Circuit Interrupter (GFCI) outlets to trip, especially during these rainy Northern Arizona monsoon summers. When they do trip they’re trying to alert you to a problem.
It makes sense for the GFCI to trip when there is a problem, but what causes them to keep tripping? What should you do if your GFCI outlet keeps tripping? How do you know what the problem is?
In this article, we’ll look at the most common causes for GCFI outlets to keep tripping and how to solve them.
Note – always be careful when working with electrical outlets. Shock may occur and it can do serious harm. If you don’t have experience with electrical outlets it’s best to hire a professional.
What is a GFCI Outlet?
GFCI outlets are power outlets that have their own breakers built in. The purpose of a GFCI is to prevent a ground fault. When they detect even just 5mA of leakage between the hot wire and ground, the outlet will trip to protect anything plugged into the outlet. This also keeps you from getting shocked when you attempt to plug something into the outlet (which is something I’ve appreciated more than once).
GFCI outlets are required anywhere there could be water such as in kitchens, bathrooms, laundry rooms, garages, crawl spaces, unfinished basements, and outdoors. GFCI outlets can be used for any 125-volt, single-phase, 15 or 20 amp circuits.
They’re great for protecting you against electrical shock, fire, and damage to appliances, but they can be annoying if they keep tripping for seemingly no apparent reason or if the problem is difficult to find. To help solve the problem, here’s a look at the main reasons the GFCI outlets keep tripping and what to do about them.
1. An Actual Ground Fault
If the GFCI detects a ground fault leakage of 5mA it will trip. This leakage is caused by a hot wire touching the ground somewhere on the electrical line such as an appliance or even the outlet itself. This can be caused by water, wires touching, dust or debris, etc.
Worn out insulation – Insulation can become worn out or damaged over time. Especially in older wiring, insulation can dry out and crack. If there isn’t enough insulation it can cause an electrical leak where the wires are too close, which in turn trips the GFCI breaker.
Electrical wiring deterioration – Wiring can wear out over time. This is especially true of wiring that’s pinched or pulled too tight when it was installed. It can break at those stress points.
Conductive dust or debris – Accumulated dust or debris can also cause enough leakage to trip if the dust or debris is wet or conductive.
Moisture – Moisture anywhere in the line will trip the GFCI. This is the most common problem for outside outlets. Water can get into outdoor electrical boxes if they’re uncovered or if there’s an excessive amount of rain or high humidity. Moisture can also get inside the wiring of an appliance.
Make sure to protect the outlet with a hermetic or waterproof cover. If there’s water in the GFCI, trip the breaker and use a blow dryer to dry out the receptacle box. Once the outlet is completely dry, reset the GFCI.
Unplug everything from the outlet and see if the GFCI stops tripping. Plug everything back in one at a time to see which appliance is causing the breaker to trip. Check that appliance (or have it checked by a professional) for wear or damage.
You can test the leakage with a good quality leakage current tester. If you detect leakage then the appliance should be repaired.
2. An Overloaded Circuit
GFCI outlets can handle 15 or 20 amps. This is fine for the most common uses. If there are too many things plugged in and drawing too much current the breaker will trip to protect from overheating. In this case, the outlet is doing its job.
Lots of things can overload the circuit including permanently installed electric motors, fluorescent lighting, lines with lots of splices, and even electrical lines with longer than 100 feet can keep the GFCI tripping.
Another possibility is a defective appliance drawing too much current. This can be caused by bad connections or corrosion, or the appliance wearing out. In this case, the appliance needs to be repaired.
The best way to test this is to limit what’s plugged into the outlet to see if the problem goes away. If the appliance is not bad, then you might need a dedicated circuit just for that appliance in order to limit the amount of current going through the GFCI.
3. A Bad GFCI Outlet
All electrical components degrade over time and GFCI outlets are no different. They’ve been known to be good for up to 25 years, but they can fail much sooner than that. Many recommend replacing them every 10 years. Replacing the outlet requires electrical training or an electrician.
They should be tested every month by pressing the test and reset buttons. If the breaker will not reset then the GFCI outlet itself will need to be replaced. You can also test the GFCI with a ground fault receptacle tester.
Even if the GFCI outlet is good, the problem can be inside the outlet itself. For example, I’ve seen the ground wire come loose inside the outlet and touch a hot wire.
4. Something Else is Bad on the Circuit
If replacing the outlet doesn’t solve the problem there could be another outlet on the line that’s bad or something that’s plugged into them that’s bad. It could also be a bad circuit breaker.
Troubleshoot all of the outlets on the same line by unplugging everything that’s plugged into them to identify if the problem is with an appliance or outlet. You might need to test each outlet individually.
Those are the most common causes and fixes for when a GFCI outlet keeps tripping. The problem can be external, such as water or an appliance, too many things plugged in and overloading the circuit, with the GFCI outlet itself, or something else downstream on the same electrical line.
Always be careful when testing electrical outlets. If you’re not experienced, then it’s best to hire an experienced and qualified professional.