Why Does My Furnace Keep Shutting Off?

Why Does My Furnace Keep Shutting Off?

A furnace that shuts off on its own is a problem you cannot just ignore. This is a common issue for Lucas, TX homeowners who use furnaces in heating their homes. It could be annoying that you cannot completely relax because your furnace constantly kicks on and later shuts off. But why does this happen?

Here are the main reasons why this short cycling takes place in your furnace.

  • Overheating Heat Exchanger Because of Low Airflow

The heat exchanger is the part of your furnace that heats the air. When it gets extremely hot due to lack of airflow, short cycling happens.  The heat exchanger trips the high limit switch when it gets too hot. Then the high limit switch will shut your unit down to protect your furnace.

Dirty air filters, dirty blower wheels, and close air supply vents are the three main reasons why low airflow is obtained, which also cause the heat exchanger to overheat over the course of its operation. Make sure to change your filter and blower wheel and open your supply vent to avoid overheating.

  • Your Flame Sensor Rod Might Be Covered With Dirt

One reason that keeps your furnace from shutting down is that your flame sensor rod is completely covered with dust. But how does it create a short cycling in your furnace?

A flame sensor rod is a device created to detect flames in your furnace burners. The device will immediately shut the gas valve off when there is no flame detected. But if your flame sensor rod is covered with dust, it cannot tell if there is a flame or not and will shut your gas valve off. Remember that if there is no gas, there is no flame and no heat available for your cold day. Make sure to check your flame sensor rod regularly to remove the dust. Call your HVAC company to do a professional cleaning.

  • Your Furnace is Too Large

Over-sized furnaces can heat your space too fast, which can cause it to frequently turn on and off. Call a professional to identify the capacity of a furnace needed for the size of your home. Do not buy another unit without consulting an expert, or else you will end up with the same short cycling problem.

If you frequently experience short cycling in your furnace unit, do not delay calling a professional service. Running your unit while it is in its poor condition might lead to costly repairs if not solved earlier. Call LoveJoy HVAC today so we can identify what causes your furnace to short cycle.