Updated: May 23
If your only experience with electricity is knowing to turn the breaker off when you change a fixture in your home, then this article is for you. Especially if you’re endeavoring to install your own roof heat trace cable in preparation for the coming ice, snow, and frigid temperatures. Trust us, Winter will arrive before you know it.
A critical aspect of installing any electrical appliance in or on your home is ensuring the proper ground fault protection. These GFCIs (Ground Fault Circuit Interrupter) are usually located in the areas of your home where there’s a danger an appliance might come in contact with water and pose an electrocution risk.
For example, if you’re doing the dishes and your son is making cookies on the counter next to the sink, there’s a chance the hand mixer might fall into the sink and end your life. No, we’re not being dramatic – ground fault protection is that serious. In this case, the GFCI outlet in your kitchen, sometimes called a GFI outlet, will recognize the short circuit and immediately cut the power to the appliance. Life saved.
Now that you understand how important it is to equip your heat cable with ground fault protection, the question becomes, “Which type?” There are a host of different protection devices from which to choose. GFCI, AFCI, GFEP, etc., etc. It’s an electrical alphabet soup.
“Is there one that’s best for heat trace cable, or does it matter which one I use?” That’s a great question, and since breakers are made for different purposes, getting that answer wrong could result in severe damage to your cable or even your home.
A great rule of thumb when differentiating between GFCI and GFEP (Ground Fault Equipment Protector), for example, is that GFEP is designed to protect heavy electrical equipment from short circuits and damage. GFCI, on the other hand, is designed to protect human beings from electric shock.
When considering roof heat cable, there are two basic types: Self-regulating and constant wattage. Each requires a different breaker. The National Electrical Code stipulates that self-regulating heat cables need GFEP, also known as an Equipment Protection Device or EPD. These protective tools can come in various forms: A device built into the power cord of your heat tape or integrated into an electrical control box, or a breaker in your house panel.
The reason self-regulating heat cable requires GFEP is that it adjusts its heat output as the ambient temperature fluctuates. It has a special conductive core that consumes less energy but requires a larger circuit breaker. These current fluctuations can quickly overwhelm a GFCI device, causing ‘nuisance trips.’
Even though the cable is fine, a GFCI will read the temperature fluctuations as a short-circuit and turn the power off. Hence the word’ nuisance,’ particularly when you’re in the middle of a blizzard and the snow is piling up on your roof.
Only GFEP protection is designed to tell the difference between the fluctuation of regular operation and a short-circuit caused by cable damage because GFEP has a higher trip load rating of 30 milliamps. A typical GFCI’s rating is only five milliamps.
Constant wattage heat trace cable delivers the same wattage throughout the entire cable and does not fluctuate its output according to outside temperatures. Thus, it consumes more power because it is always on at the same wattage level until the thermostat reaches the programmed temperature to turn it off. Electrical code requires a GFCI protected outlet for constant wattage cable because it does not have the same electrical draw as self-regulating cable.
By winterizing your roof with heat cable, you’re acting to protect your home against the damaging effects of snow and ice accumulation and giving yourself and your family a sense of peace when winter storms blow through your area. The last thing you want is for the heat cable to cause problems or not work because of improper installation.
Even though installing roof heat trace cable by yourself can be tricky for a person with no electrical experience, it’s not impossible. If you feel overwhelmed or intimidated, it doesn’t hurt to consult a professional heat cable installer. They have been doing these kinds of installations for years and should be up-to-date with the latest electrical code. Roof heating cable kits also come with specific electrical specifications and instructions to help you do the job right.
Finally, here is a great how-to video our partners over at Wasatch Heat Cable have put together to explain the differences between breakers and to walk you through the process of installing the correct one for your roof heat cable: https://www.youtube.com/watch?v=24UKZzB2tnM&t=162s. Stay tuned to our blog for additional tips and helpful articles on heat cable, de-icing, and roof snow removal.