So you just had to reset the circuit breaker for your furnace. And now you’re wondering what caused this to happen. Will it keep happening? And what you can do to keep it from happening again?
Here’s the key: If resetting the breaker worked and it hasn’t tripped again, you’re probably fine. It might have been caused by a temporary power surge or spike from a thunderstorm or electrical grid problem. Just keep an eye on your furnace.
However, if your furnace continues to trip your circuit breaker, you need to find the source of the problem and fix it. The most common problems are:
- An overloaded furnace
- An overloaded shared circuit
- Short circuit or ground fault inside your furnace
- Circuit breaker problems
But first, do not keep resetting a tripping breaker. That’s dangerous. Here’s why…
Why you shouldn’t keep resetting your furnace breaker
Circuit breakers are safety devices that help prevent home fires.
Each wire in your home is rated to handle a certain amount of electrical current (measured in amps). If too much electrical current passes through your wires, they can overheat, melt, and cause a fire.
Circuit breakers prevent this by automatically shutting off electricity to circuits when too much electricity is passing through them.
For example, most furnace breakers are 15-amp breakers. If more than 15-amps of electricity flows through it, the breaker will trip and turn off electricity to that circuit to prevent the wires from overheating.
So now that you know the importance of contacting a professional if your furnace breaker keeps tripping, we’ll show you some of the most common reasons these breakers trip…
Cause #1: Overloaded furnace
An overloaded furnace is working harder than it should, causing it to pull more electrical current than it normally does. If your furnace turns on, works for a little while but then quickly trips the breaker, this is likely the problem.
Several problems can cause your furnace to become overloaded, including:
- A dirty air filter—A dirty filter suffocates your furnace. It has to work extra hard to suck in air from your home. Imagine having to breath through a towel. You can do it, but it’s much more difficult.
- Closed or blocked air vents—Blocked return vents (the ones that suck air into your furnace) cause the same problem as a dirty air filter. Closed supply vents make it more difficult for your furnace to blow air into your home (like you having to blow through a straw).
- Restricted ductwork—Some of the ducts in your home may be crushed, kinked or bent too sharply, restricting airflow to and/or from your home. (Seeing a theme here?)
- Malfunctioning part—A bad part inside of your furnace can cause the furnace to have to work harder, pulling more electrical current.
How to fix it: Make sure your air filter is clean and all your vents are open and clear of obstructions like drapes or furniture. Even vents in unused rooms should be open. Look in your attic or crawlspace for crushed or kinked ductwork and fix it, if you can.
Contact a heating repair company if you can’t fix the problem yourself or think a part might be malfunctioning.
Cause #2: An overloaded, shared circuit
It’s best if your furnace is on its own circuit. However, many older homes in Atlanta were not built this way. Your furnace might share an electrical circuit with some other outlets or lights in your home.
Running your furnace and another larger electrical appliance (perhaps power tools in the garage) on the same circuit can overload your circuit. The 2 combined appliances may pull more amps than the circuit is rated for.
How to fix it: You can remove other appliances from the furnace’s circuit or simply not run them when the furnace is on. Otherwise, consider moving your furnace to its own circuit.
Cause #3: Short circuit or ground fault in your furnace
A furnace that starts up but immediately trips the breaker can be caused by an electrical short circuit or ground fault inside of the furnace itself.
Short circuits in your furnace happen when a bare hot wire comes in contact with a neutral wire.
Ground faults occur when a bare hot wire touches a ground wire or some other grounded part in your furnace (like the metal box).
Both short circuits and ground faults greatly increase the amount of electrical current your furnace is pulling, which trips the breaker. They’re most often caused by malfunctioning parts, an incorrect repair, or a rodent chewing some of the wires.
How to fix it: You need to find the source of the short circuit or ground fault inside of your furnace. Unless you are familiar with how appliances and electricity work, this is best left to a certified technician.
Cause #4: Circuit breaker problems
It’s also possible that the problem lies not with your furnace but with the circuit breaker or electrical panel. Your breaker may be bad or some of its electrical connections may be loose.
How to fix it: Depending on the problem, the solution could be tightening electrical connections, replacing the breaker or—in extreme cases—replacing the panel.