Furnace Limit Switch: What is It? Operating Principles & Problem-Solving

A furnace system consists of different tiny and massive components that are essential to warming up your home. A furnace limit switch is one of the components that play a significant role in producing heat. A furnace limit switch is designed and included in the furnace system to control the functioning of the furnace blower assembly.

The switch shuts down the furnace system if it overheats. This might break down and cause the furnace system to work improperly. Do not wait to call for a heating replacement in Layton, UT. It’s essential to check and fix the malfunctioning furnace system immediately.

What is a Furnace Limit Switch?

A furnace limit switch is a part of forced air distribution HVAC systems responsible for switching on the furnace blower when the temperature inside the furnace system has reached the desired value.

It helps to regulate the temperature in conjecture with a thermostat to ensure optimal heating in your home. Apart from its safety feature that shuts down the furnace system when overheated, it has a manual switch-on button to keep the fan running continuously to improve the airflow.

Our heating installation experts in Ogden, UT, advice to locate the furnace switch first. It is easy to locate it as it consists of an exterior plate and a temperature probe under the furnace’s supply plenum.

Functioning of Furnace Limit Switch in The HVAC System

As soon as you switch on the furnace system, the thermostat signals the furnace to turn on the unit. The furnace limit switch turns down, connecting the circuits and switching on the blowers.

The burners will burn until the room temperature matches the thermostat temperature. The burner shuts down as soon as the room reaches the desired temperature. However, the blower continues to run to lower the temperature inside the furnace system to the lower limit permitted by the furnace.

Signs of Malfunctioning Furnace Limit Switch

Here are the signs a furnace system displays if there is an issue with the limit switch requiring emergency service by our skilled heating installation expert in Ogden, UT:

  1. The furnace blower runs continuously.
  2. The furnace system distributes cool air.
  3. The furnace system is struggling with short cycling issues.

Common Problems With a Furnace Limit Switch

Here are some common problems with limit switches:

  • The sensor on the limit switch starts to wear down with time. Keeping it neat and clean is better to avoid degradation due to excessive dust and grime.
  • A clogged air filter can cause the plenum to overheat. The furnace limit switch will shut down the entire furnace operation.
  • The blower motor assembly overheats if you run the furnace system continuously. It will cause the limit switch to activate the safety function and trip down to shut the furnace system.

To Conclude

A technician may suggest replacing the limit switch if you call for a heating replacement in Layton, UT. It is easy and inexpensive to replace the limit switch as a DIY task. Still, specialists will advise you to always call a skilled technician to fix the issue to avoid injuries or worsening of the problem.

E.R.S. Heating & Cooling technicians are here to help homeowners resolve their comfort problems. Call us at (801) 732-6020 or email us, and we will find an effective and cost-friendly solution to maintain your home comfort.