Modern gas furnaces have a number of safety mechanisms that ensure they work safely. These safety features are also designed to protect your heating system. The reset button pops out whenever there is a problem, like an interrupted gas supply, empty oil tank, or overheating occurs. The reset button will also pop out if there is an electrical issue. Today we’re going to take a closer look at furnace reset buttons and the specific role they play in your heating system.

How a Furnace Reset Button Works

If the reset button is ever tripped, you will need to use the button to reset your furnace before it runs again. The reset button works in tandem with the furnace’s limit switch. The limit switch measures the temperature inside the furnace and air handler where the blower fan is located. If the temperature of either the blower fan or the furnace itself rises above a set level, the limit switch will immediately trigger the reset button to shut down the furnace.

The blower fan and furnace are only designed to be able to withstand so much heat. If the heating system continued to run when it was too hot, it could easily begin to melt the electrical wiring and damage various components. Electrical issues that cause a reset button to pop could be as simple as a power outage or stem from more serious issues.

Locating Your Furnace’s Reset Button

The location of the reset button can vary from system to system, depending on the make and model of your heating system. The reset button is almost always located inside the air handler that is either next to or above your furnace. All systems have a door that allows access to the air handler compartment, but you may need to remove screws to take off the door.

In most newer systems, the reset button is located directly next to the blower motor. If your system is older, the button may be harder to spot as it is sometimes underneath or behind the blower motor.

The reset button is often made of yellow or red plastic to make it easier to spot, and it also usually is marked with a large “R.” You can check to see if the reset button is tripped by seeing if it is flush with the surface or sticking out. If the button is sticking out, it means that it has tripped, and you need to reset your furnace.

How to Reset a Gas or Oil Furnace

Before you reset your furnace, you will first need to shut off both the gas and electricity. If you have an older furnace with a standing pilot light, all you need to do is close the main gas valve. Most newer furnaces have an electronic igniter, and in this case, you will also need to flip the circuit breaker to shut off the electricity to the system. After shutting off the gas and electricity, you will then need to turn your heating off at the thermostat and then wait for at least five minutes before continuing.

If your furnace has a pilot light, the next step is to relight the pilot. You can now turn the electricity back on by flipping the circuit breaker, and then go back to the furnace and open the gas valve again. If your furnace has an electronic igniter, you can simply wait for five minutes and then turn on the electricity, followed by the gas.

The last step is to press the reset button and hold it in for at least 30 seconds so that the furnace resets. You can now turn your heating back on and turn the thermostat back up to where the furnace should start. If the furnace starts and continues to run, then you’re all set. If the reset button quickly trips again after the furnace starts, you will want to wait for around an hour before you try to reset it again.

The most common reason that the reset button will trip again is that the furnace shut off due to overheating. When this happens, the furnace and the blower motor both have to cool down, or else the limit switch will quickly trigger the reset button again once the heating system starts back up. This is why you should wait at least an hour before trying to reset your furnace a second time. If the reset button trips a second time, then you will need to have your heating system inspected, as continually trying to reset it can result in damage.

Resetting an Electric Furnace

Resetting an electric furnace is even easier. The first thing to do is shut off the power by flipping the circuit breaker. If your furnace has a power button, all you need to do is flip the switch off to shut off the electricity.

Once the power is off, you can then open up the air handler and press the reset button. Continue holding the button in until you hear or feel it click. You can then turn the power back on, and your furnace should immediately start as soon as the thermostat signals that your heating system needs to run.

What Causes the Reset Button to Constantly Trip?

Overheating is the most common reason that the reset button will trip. Furnaces typically overheat because there isn’t enough cold air being drawn into the system, which means that most of the heat that the furnace produces will remain trapped inside the unit.

If you haven’t replaced your air filter within the past month or two, you will want to replace the filter before you try to reset your furnace, as a clogged air filter is the most common cause of overheating. You should also check that most of your supply vents are open and that neither the supply nor return vents are clogged or obstructed, as these issues can also reduce the airflow and cause the furnace to overheat.

If your air filter is clean and your vents are open and not clogged, then most likely, the reason that the reset button keeps tripping is because of an electrical issue. This could be something like a loose connection, damaged wiring, or something else that is causing a short and overloading the heating system’s electrical circuit. This is obviously something that you will want to have looked at immediately since you will be left without heat until the issue can be repaired.

Contact the Professionals

At Express Plumbing Heating & Air, located in Brush Prarie, WA, our certified technicians can quickly get to the bottom of your furnace issues and determine the best way to overcome them. We repair all types of furnaces as well as air conditioners, and we also offer heating and cooling maintenance and installation services. In addition, if you need any plumbing, drain, or sewer services in the Boise, Nampa, or Caldwell areas, our team of licensed plumbers can assist with that as well. Give us a call today to schedule a furnace inspection or to give your heating system a tune-up.

Brad Jordan

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