There are a number of components that play a key role in the operation of a furnace during the cold parts of the year, and some of these are primarily in place for safety and prevention of any dangerous incidents. One great example here is known as the furnace limit switch, or simply the furnace switch, but it’s one that many home and building owners aren’t actually aware of.

At Lee’s Heating and Air, we’re happy to offer a wide range of furnace services to clients in Provo and nearby parts of Utah, including furnace maintenance, furnace repairs and even brand new furnace installation if your model has worn down or become heavily damaged. We also provide basic expertise to many clients during our visits, helping them understand the various components that are working in their system plus how to check on them periodically. With this theme in mind, let’s go over some basics on the furnace limit switch – what it is, why it’s important, and how to trouble shoot some of the simpler issues that can take place with this switch from time to time.

What is a Furnace Limit Switch?

If you’re unfamiliar with this switch, it’s actually a safety feature that is built into the majority of furnaces today. It works to shut off the furnace if the temperature inside your home gets too hot or too cold, helping protect you from potential fire hazards and other dangerous incidents.

Basically every furnace built today will have one of these switches, which may operate slightly differently depending on your fuel source. For gas-powered furnaces, the switch will be connected to a temperature sensor located near the heat exchanger, helping monitor any rapid changes in temperatures. If it is tripped due to an extreme change in temperature, it will shut off electricity to the furnace until you reset it manually.

For electric-powered furnaces, the switch will be connected to a fan motor that is usually placed near the blower. When this overheats or overspins, it can cause an issue with your furnace and the limit switch will kick in to shut off the power in order to prevent any further damage from occurring.

Why is the Furnace Limit Switch Important?

As you may have already guessed, the furnace limit switch is a critical part of the operation of your furnace, especially during the winter season. Without it in place, dangerous temperatures can easily be reached within your home, putting it at risk for fire or other serious incidents. In addition to this, it helps stop any further damage from taking place if something were to malfunction with your furnace as well.

Overall, it’s very important to keep your furnace limit switch in proper working condition at all times. That way you can ensure that your family is safe and warm throughout the winter season without any worry of a potential emergency from occurring.

Possible Minor Issues With Furnace Switches

Whether due to debris buildup, physical damage or some other issue, it’s possible for certain minor issues to arise with furnace limit switches over time. Here are some possible concerns:

  • Dirt buildup: As the switch operates, dirt and debris can slowly build up on its surface. This can inhibit its ability to function properly if left unchecked, so you should periodically inspect it for any blockages or damage that could be preventing it from working correctly.
  • Physical damage: It’s also possible for the physical switch itself to become damaged or worn over time. In this case, you should replace it immediately in order to keep your furnace running as efficient and safely as possible.
  • Blown fuse: If you find that your furnace limit switch isn’t working at all, it’s possible that a blown fuse may be to blame. In this case, reset or replace the fuse as needed in order to restore power to the switch and get your furnace back up and running.
  • Improper initial wiring: Down related lines, one issue that actually speaks to improper installation of the switch is if the wiring isn’t correct to begin with. In this case, seek out a professional to inspect and repair any wiring issues that may be present.

By understanding these key aspects of furnace limit switches, you can take better steps towards keeping your home safe and warm during cold weather seasons.

Preventing Furnace Switch Issues

There are also some basic steps you can take to prevent the above issues from ever cropping up:

  • Ensure quality installation: If you’re purchasing a new furnace at any point, make sure to only trust professionals with the installation. This will help ensure that all wiring is done correctly and prevent any potential issues from occurring due to improper setup.
  • Regularly clean and inspect: Keeping your furnace limit switch clean of debris and dust can go a long way towards ensuring its proper functioning and longevity. Inspect it for any damage or blockages, and be sure to replace it as needed when any physical issues become apparent.
  • Check the fuse: As mentioned above, a blown fuse can cause your furnace switch to not function properly. Make sure to regularly check for any problems with the fuse and reset or replace it as necessary in order to get your furnace back up and running quickly.
  • A basic reset: If your furnace switch seems to be malfunctioning for no apparent reason, it’s often possible to simply reset the switch and get it back up and running. This can be done by manually pressing the switch or flipping a nearby circuit breaker if one is present.

By following these simple steps, you can help ensure that your furnace limit switch continues working safely and efficiently all season long.

For more here, or to learn about any of our HVAC services in Provo or other parts of Utah, contact our team at Lee’s Heating and Air today.