A GFCI (ground fault circuit interrupter) outlet is a special type of electrical outlet designed to shut off electricity automatically if there is a problem. When the red light is on but there is no power, it typically means the GFCI has tripped and needs to be reset. This usually happens when there is a ground fault, which is an abnormal flow of electrical current from the hot wire to the ground wire. There are a few common reasons why a GFCI might trip, which we’ll explore in more detail below.
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What is a GFCI Outlet?
GFCI outlets provide an extra level of protection against electric shocks. They work by detecting small differences in current flow between the hot and neutral wires. Under normal conditions, the current on the hot wire should match the current on the neutral wire. But if some of the current is leaking through to the ground wire instead, that means there is a ground fault. The GFCI senses this and cuts off power to prevent harm.
GFCI outlets have a built-in circuit breaker that trips when it detects a ground fault of around 5 milliamps or more. For comparison, it takes as little as 10-20 milliamps to cause harm to the human body. So GFCIs provide an important safeguard against electrocution.
Where are GFCI Outlets Required?
GFCI outlets are required in bathrooms, kitchens, basements, garages, outdoor outlets, and other areas where electrical outlets are near water sources. This helps prevent shocks or electrocution from appliances near water. They are also required for outlets with crawl space access.
How Do You Reset a GFCI Outlet?
Resetting a GFCI outlet is easy. Just locate the “Reset” button on the outlet (it will be colored red or labeled RESET) and firmly push it in. You should hear a click. This will reconnect the power.
If the red light turns back on and the outlet stops working again, that means there is still a ground fault present.
Common Causes of GFCI Tripping
There are a few common reasons why a GFCI might trip, causing the red light to turn on:
1. Faulty Appliance or Damaged Cord
One possibility is that you have a faulty appliance or damaged power cord that is causing a ground fault. Try unplugging all appliances from the outlet and resetting. If the GFCI stays on, then plug in each appliance one at a time, resetting in between each one. If the GFCI trips when a particular appliance is plugged in, that indicates the appliance either has a short circuit or damaged power cord that is allowing current to leak.
2. Moisture or Water Exposure
Since GFCIs are designed to detect abnormal current flows, exposure to water or moisture can also cause them to trip. Condensation from humid conditions, spills, or leaks can allow some current to flow to ground. Make sure the outlet area is clean and dry before resetting. Look for any water in the surrounding area that could be causing the issue.
3. Loose Wiring
Loose electrical connections in the wiring behind the GFCI can create a ground fault. As vibration happens over time, wires can become loose from the terminals. Check that all wires are securely attached. You may need an electrician to open up the outlet and inspect the condition of the wiring.
4. Bad Weather and Electrical Surges
Power surges from lightning strikes or other severe weather can sometimes cause GFCIs to trip. Reset the outlet after the storm passes and the electrical system stabilizes. If it was just a temporary surge, the GFCI will likely stay on after resetting.
5. Overloaded Circuit
In some cases, having too many appliances running on one circuit can cause the GFCI to trip. Try plugging some devices into other outlets on different circuits to lighten the load. The GFCI may reset normally after lowering the amount of current being drawn.
6. Old or Damaged GFCI
If the GFCI outlet is old, it may simply not be working properly anymore. GFCIs should be replaced every 5-10 years or after major electrical events like lightning strikes just to be safe. If the outlet won’t stay reset or frequently trips for no clear reason, it’s best to replace it with a new GFCI outlet.
Diagnosing the Cause of a Tripped GFCI
If you’ve tried the basic troubleshooting tips but your GFCI outlet is still tripping with no obvious cause, there are a few steps an electrician can take to diagnose the specific fault:
Electrical Testing
An electrician can use a multimeter to test the outlet wires for current leaks, shorts, and abnormal resistance levels that could point to a ground fault. They can measure hot to neutral current and compare it to hot to ground current to pinpoint any leakage.
Check the GFCI Circuit
The electrician will check that the GFCI outlet wiring is correct and that downstream outlets are wired properly on the load terminals. Any miswired connections can cause nuisance tripping.
Inspect the Service Panel
Issues at the main electrical service panel like a bad breaker or loose neutral line can also cause GFCI outlets to trip. The electrician will examine the panel for any problems and fix as needed.
Look for External Damage
Critters, nails, or other external factors could have damaged the GFCI wiring behind the scenes. The electrician will open it up and check for any punctures, stripped wires, or broken connections.
Electrical Safety Tips Related to GFCI Outlets
While diagnosing a tripped GFCI, keep these electrical safety guidelines in mind:
– Don’t keep resetting a tripped GFCI without addressing the underlying issue. This could lead to an electric shock.
– Only plug one high-wattage appliance into each outlet at a time. Overloading can cause trips.
– Make sure outdoor outlets have weatherproof covers. Moisture is a common GFCI trip cause.
– Regularly check for loose plugs or damaged cords. These can create ground faults.
– Don’t use extension cords or power strips with GFCI outlets. Only plug devices directly into the outlet.
– Install GFCIs in any outlets near water sources like kitchens, bathrooms and basements. This adds important protection.
– Replace old GFCI outlets that are 10 years old or more. Components can deteriorate over time.
– Address tripped GFCIs quickly! They indicate a real shock risk is present.
When to Call an Electrician for GFCI Issues
In many cases, you can troubleshoot a tripped GFCI outlet yourself. But if you try all the basic steps and the GFCI still won’t reset or continue tripping, it’s safest to contact a licensed electrician. Professionals have the tools and knowledge to fully diagnose and fix:
– Faulty wiring connections
– Damaged GFCI outlets
– Overloaded circuits
– Short circuits
– Current leaks
– Service panel problems
– Electrical surges
Repairing these types of issues requires electrical training and experience. Don’t attempt to fix complex problems yourself. Instead, have a qualified electrician inspect the GFCI and wiring to determine the necessary repairs.
Conclusion
When a GFCI outlet isn’t working, start by resetting it. If it trips again right away, unplug all devices and reset again. Then plug in each appliance one-by-one, resetting in between to check for faults. Inspect for water or moisture issues near the outlet as well. If the GFCI won’t stay on after basic troubleshooting, have an electrician inspect the outlet, wiring, and service panel to diagnose the specific electrical issue causing the problem. Address GFCI trips promptly since they indicate a shock risk is present.