7 Issues That Can Cause Your Electric Furnace to Not Turn On
Finding that your electric furnace suddenly won’t turn on when your home starts getting cold can be incredibly frustrating and may lead you to think that you need to have it replaced. This problem can occur for a variety of different reasons, some of which are fairly minor and easy to fix. While you should never attempt to do any work on an electric furnace yourself, there are a few things you can still check before calling an HVAC contractor. Today, we’re going to discuss the potential reasons why your electric furnace isn’t turning on as well as how to spot the signs of these problems and how they can be fixed.
1. Power Switch Is Shut Off
If you’re lucky, the problem may be simply that someone has turned your furnace’s power switch on. The power switch is obviously what controls the electricity to the unit. If the switch isn’t flipped on, no power will flow and the furnace won’t run. The switch should be located either next to your furnace or the side of the unit, and it usually resembles a light switch. If the switch isn’t marked or you’re unsure of which direction is on and off, you can try to flip the switch to the opposite direction and see if the unit then starts.
2. Tripped Circuit Breaker
If your furnace’s power switch is turned on, the next thing you’ll want to do is check to make sure that the circuit breaker isn’t tripped. Depending on how your system is set up, the furnace circuit breaker may be in your main electrical panel or in a separate sub-panel near your furnace.
The circuit breaker is designed to instantly trip and stop power flowing to the furnace if the circuit ever gets overloaded due to a short or some other issue. If you do find that the circuit breaker is tripped, you should turn your heating off at the thermostat before resetting the circuit breaker. Once you’ve reset the breaker, you can then turn the heat back on and the temperature up to see if your furnace now starts. If the circuit breaker trips again, you will need to have your furnace inspected as this indicates that there is a loose electrical connection, damaged wiring, or some other issue causing the circuit to overload.
3. Blown Furnace Fuse
All electric furnaces have built-in fuses that are designed to prevent damage from overheating. If the furnace ever overheats, the fuse will sacrifice itself so that it burns out instead of the entire furnace burning out. Should you ever have a fuse burn out, your furnace won’t ever start until the fuse is replaced.
The fuse box should be located within an access panel somewhere on the unit, and you should easily be able to tell if a fuse is blown when looking inside the box. While replacing a blown fuse is potentially something you could do on your own, we wouldn’t recommend it. You could easily cause further issues if you don’t use the right fuse or accidentally damage any of the wiring or other components.
4. Overloaded Furnace Blower Motor That Needs to Be Reset
The blower motor is what draws cold air into the furnace and circulates the hot air it produces throughout the building. There are a number of different issues that can cause the blower motor to get overloaded and trigger both the furnace and blower to automatically shut down. When this happens, you will usually need to wait at least 30 minutes and then press the reset button so your heating system will start again. The reset button is located on the blower assembly inside your air handler. The button should be clearly marked, but you may need to have a technician reset the furnace for you if you can’t find it or are unsure of what to do.
The most common reason that a furnace and blower will shut down and need to be reset is due to overheating caused by a dirty air filter. If your furnace ever needs to be reset, you should always check your air filter before doing so and replace it if it looks black or you can’t see light through it. Overloading can also occur because the blower motor is starting to wear out, and in this case, you will need to have the motor replaced.
5. Water Damage
If your furnace won’t start, you should also check for any evidence of leaks and water damage. Exposure to water can damage the electrical components and cause a short that will prevent the furnace from running. This most commonly occurs when the furnace is in the attic as a leaky roof could expose the unit to water. It can also happen due to a leak in one of the plumbing lines near the furnace. If the damage is fairly minor, the furnace can usually be repaired but major water damage will typically ruin the unit altogether.
6. Faulty Start Capacitor
The start capacitor is what provides the extra surge of power needed for the furnace blower to start. This type of motor requires a huge amount of electricity to first start, and this is often more than the circuit can provide without being overloaded. To prevent overloading, the capacitor stores a strong electrical charge that it then releases to kickstart the motor. If the capacitor burns out or fails, it will prevent the blower from starting so no heat will flow.
A bad start capacitor is quite easy to fix by having a technician test the capacitor and replace it if necessary. This problem is usually quite easy to spot as you will typically hear a loud clicking noise coming from the blower when it tries to start. You may also hear the blower make a loud humming noise when it tries to start. If you do hear these sounds, you should immediately turn your heat off at the thermostat. You will then want to have the capacitor checked before running your heating again. If you try to continue running your furnace, you could cause the blower motor to burn out or damage any of the furnace’s sensitive electrical components.
7. Malfunctioning Thermostat or Damaged Thermostat Wiring
Your thermostat is what signals the furnace to start and stop. If the thermostat isn’t set correctly or is malfunctioning, it will prevent the furnace from running. The wiring that runs from the thermostat to your electric furnace can also get damaged and prevent the signal to run from reaching the furnace. The only real way to know if your thermostat is working properly is to have an HVAC technician inspect and test it. Depending on the specific cause, you may need to have the wiring fixed or your thermostat recalibrated or replaced.
At Dream Team Home Services, our technicians can help you quickly determine why your furnace won’t start and repair the problem so your heating again works properly. We repair all makes and models of electric and gas furnaces as well as air conditioners and other HVAC units. Our team also specializes in heating and cooling installation and maintenance services and a full range of electrical and plumbing services. Give us a call today if you need to have your furnace inspected or any other home service in the Media area.
