Why You Need a GFCI for Your In-Floor Heating System


In-floor (radiant floor) heating is an excellent option to comfortably and sustainably keep your home warm. If you're not familiar with GFCIs, you're not alone. 

Most homeowners hire a professional to install their radiant floor heating system and never give it a second thought. However, a responsible homeowner is one that is both well-equipped and informed! After all, GFCIs were created with the sole purpose of keeping you and your family safe.

GFCIs Save Lives

A Ground Fault Circuit Interrupter, or GFCI, is an incredibly beneficial addition to an electrical outlet. Before its invention in 1961, death by electrocution was an all too real risk. In fact, an average of 800 people died every year in the United States alone, just from the electrical shock of plugging something into a faulty outlet. 

Thankfully, Charles Dalziel, a professor of Electrical Engineering at UC Berkeley, dedicated his time outside the classroom to learning more about the effects of electricity on the human body. His invention of the GFCI has been an incredible lifesaver, saving an estimated 400 lives annually. 

If there was ever doubt in your mind that one person has the power to make a difference, consider that Dalziel's invention of the GFCI has saved an estimated 23,200 lives to date!

What is a GFCI and Why Should I Care?

While that might sound like a mouthful to those of us who aren't electrical engineers, it boils down to this: A GFCI is a failsafe device built into your electrical outlet or distribution panel to protect you and your family from electrocution. 

A GFCI is incredibly important to homes with in-floor heating systems, which warm your home with a series of electrical wires that run beneath your flooring. This means you have electricity running under your feet throughout your entire home. Installed GFCIs will protect you, your family, your possessions, and your home from the dangers of electrocution, which could be carried from one room to another in the event of a leak or an electrical failure.

The National Electric Code (NEC) technically defines a GFCI as, “A device intended for the protection of personnel that functions to de-energize a circuit or portion thereof within an established period of time when a current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.”

How Does a GFCI Work?

A GFCI is a safety device built right into modern electrical outlets and distribution panels to protect you and your loved ones from potential electrocution caused by the many devices you plug in. 

Outlets you use to plug in your phone charger, lamp, appliances, and other electrical devices have two slits, and sometimes a third hole centered below called “ground.” Electricity is passed from one slit (the hot side), through your plugged in device, and into the second slit (the neutral side). 

Now take a moment and look at the outlet closest to you. Do you see two buttons on it labeled “test” and “reset”?. If you do, great! You already have GFCI outlets! If not, you may not be protected from the dangers of electrocution. 

GFCIs are most commonly built right into your electrical outlets, but they can also be installed at the distribution panel to protect every circuit in your home. GFCIs monitor the electrical current passing from one slit to the other. If it detects a problem, a GFCI will stop power from flowing to that particular outlet within 20-30 milliseconds to protect you from electrical shock.

If power is cut, your smart in-floor heating thermostat will detect the change immediately, turn off your in-floor heating (if your GFCI doesn't do it automatically), and send you an alert via your smartphone or smart assistant. This is incredibly beneficial if you're not physically in the room when a power failure occurs. For example, if your GFCI detects a problem and shuts off power while you're asleep, away from home, or in another room, your smart thermostat will alert you so you're immediately aware that your home is no longer being heated. You can then check the electrical outlet, correct the problem, and get the heat turned back on. 

In the event that you require a professional electrician to do an inspection and make a repair, your concrete foundation will continue to release stored heat for 8-10 hours, keeping your home warm while you get things up and running safely again.

The Benefits of Having a GFCI for Your In-Floor Heating System

No matter how safe and well-insulated your house is, moisture happens. You may experience a water leak in your laundry room or bathroom, spill liquids in the kitchen, or be compromised by wet or humid weather. Homeowners in areas where rain is very common, like the Pacific Northwest, may not even realize moisture is seeping into the foundation of or inside their home until power is cut or electrocution occurs. 

Your in-floor heating system carries electrical currents beneath your feet, throughout your entire house. If moisture is present at one end of your house and you don't have a GFCI installed, your radiant floor heating system may unintentionally carry an electrical shock across your floor. However, with a GFCI safely installed in your in-floor heating system, that current would be stopped in its tracks.

A GFCI works hard for you; protecting you, your family, and your guests. If it detects moisture from spills, accidents, rain, snow, flooding, or humidity, a GFCI will automatically turn off your electric radiant heating system and notify your smart thermostat to alert you. Together, this smart system is a powerhouse built to keep you warm and safe. Even better, it does it all automatically so you don't even have to think about it!

Install a GFCI

The National Electric Code requires GFCIs to be installed in bathrooms, kitchens, laundry rooms, garages, accessory buildings, crawl spaces, unfinished basements, boathouses, and rooms with a wet bar. Your local regulations may impose further requirements, especially if you live in an area subject to flooding, heavy rain, ice, or snow.

If you live in a newly built home, you probably already have a GFCI installed. However, you should definitely double check – it only takes a moment and may save your life!

When installing a new electric radiant floor heating system or Mysa’s Smart Thermostat for Electric In-Floor Heating, you (or a contractor) should check for a working GFCI. This is especially important if you have children or guests. Guests often use electrical outlets in rooms like extra bedrooms and bathrooms that are used infrequently. An installed GFCI will protect your visitors from potential shock when plugging in a hairdryer or phone charger, even if there's water present. 

Similarly, young kids are prone to spilling drinks and other accidents, which could reach your radiant floor heating wires below. Again, an installed GFCI will detect any issue within 20-30 milliseconds and shut off power to your in-floor heating.

Maintaining a Working GFCI

Of course, like all electrical components, GFCIs do wear out over time, so it's imperative that you or a professional run a monthly check. Your electrical outlets will still power your devices when a GFCI wears out, but they will no longer be protected.

The American Society of Home Inspectors conducted a study of home electricity and found that “21% of GFCI circuit breakers and 19% of GFCI receptacles tested did not provide GFCI protection.” And, “in areas of high-lightning activity, such as Southwest Florida, the failure rate for GFCI circuit breakers was more than 57%!” Therefore, monthly checks are most definitely important to ensure your safety!

How to Test for a Working GFCI:

  1. Locate an electrical outlet.
  2. Press the “reset” button.
  3. Plug in any electrical device. The device should turn on immediately.
  4. Press the “test” button. If the GFCI is working, power will be cut and the device will turn off.
  5. Press “reset” again and the device should turn on again. If it does, the GFCI is working. If it doesn't turn on, the GFCI is not working.
  6. Repeat this test at each outlet or distribution panel monthly.

If you find that any GFCI is not working properly, it's imperative that you hire a trained electrician to fix it immediately, preferably before using your radiant floor heating system again. The problem may seem minor, but if gone untended, it could short the electricity of your in-floor heating.

The Power Combo: a GFCI, In-Floor Heating, and a Smart Thermostat

Radiant floor heating is a welcome addition to any home, keeping it comfortably warm far longer than forced air and baseboard heating systems. Paired with a smart thermostat designed to control in-floor heating and a working GFCI, you and your family will stay safe and warm year-round. 

Now's the time! Go check and test your outlets and distribution panel for a functional GFCI!

by LastSale
by LastSale