Furnace High Limit Switch Keeps Tripping Causes and Fixes

A high limit switch is a safety feature on the furnace which restricts the furnace from overheating and causing further problems. Sometimes it happens that the furnace high limit switch trips and switches off. These can be caused due to many reasons and need to be fixed immediately by an experienced service provider.

We will discuss some of the main reasons that cause the high limit switch to trip and suggest some of the best measures you can take to prevent it from doing so. Being one of the best HVAC companies in Yucca Valley, we will provide you with the best fixes for the problem.

What Causes the Furnace High Limit Switch to Trip?

Some of the common reasons which cause the furnace high limit switch to trip are given here. Along with it are mentioned the fixes for each of the causes.

1. Dirty Air Filters

Dirty air filters can block the airflow, and thus the furnace may heat up. This overheating causes the heat exchanger to become too hot, and this, in turn, trips the switch.

The best fix for this is to contact a professional team and get the air filters cleaned. Cleaning the air filters will allow the air to pass, and thus this will help maintain a stable temperature in the furnace.

2. Blocked Vents

The vent present in the furnace helps in the easy flow of the gases. If something is blocked in the vent, then the gas will have no way to escape, and thus, the furnace may get choked with gas leading to tripping of the high limit switch.

Ensure that nothing is blocked in the vent and find an easy way to vent the gas once the flame burns. You can also seek assistance from a professional advisor.

3. Less Efficient Blower Motor

When the blower motor does not give sufficient air, the heat exchanger may overheat, and thus the switch may trip on, reaching a higher limit.

Check the blower motor once. You can either get the blower motor repaired, or you may have to get it replaced if the service provider suggests doing so. If the blower motor has become too old, it is advised to replace it. This will provide long-term results.

4. Clogged “A” Coil

A-Coil is provided in the furnace system, which works as a split air conditioner. Sometimes the “A” coil may get clogged with debris, affecting the furnace’s working. This can cause the furnace system to heat up and trip the high limit switch.

You can get the “A” coil cleaned to remove the debris. Sometimes the A-coil may get exposed to air, water, and moisture, damaging the coil completely. In this case, you can get the coil replaced.

5. Bad Furnace High Limit Switch

There are greater chances that the high limit switch is caused due to the switch itself. The switch may work inappropriately after many years of use or non-durable products. In this case, you have to get another high limit switch fixed to your furnace system.

Diversified Heating and Cooling has immense experience in furnace repair in Yucca Valley. You can read about our customers’ feedback on the website. You can contact us at 760-418-0426. You can also visit our office for a detailed discussion of any problems you are dealing with with your furnace or HVAC system.