Why is My Furnace Running Constantly?

Furnace cycles are an essential part of maintaining a comfortable and consistent indoor temperature during the cold winter months. But if your furnace never seems to shut off, you’re likely wasting significant energy and putting unnecessary stress on your heating system.

To help homeowners heat their homes more efficiently, the experts at Evergreen Heating and Cooling will discuss why a furnace might be running constantly, as well as suggest some solutions. Contact us today to schedule furnace services in Waco, TX, and the surrounding areas.

How Do Furnace Cycles Work?

Furnaces are designed to run in cycles. Typically, you’ll hear your heating system kick on and it’ll run for 15-20 minutes. Throughout the cycle, you should feel warm air flowing through your vents. 

After 15-20 minutes, the cycle should end, and the system will turn off until it’s time to begin the next cycle. This cycle repeats as often as needed to maintain the set temperature, ensuring that your home stays warm and comfortable while also conserving energy by not running continuously.

Cycle frequency will typically depend on the outdoor temperature, the set temperature on the thermostat, and your heating system’s overall efficiency. However, there should be a clear beginning and end of each cycle. If there isn’t and your furnace is seemingly always running, your system is likely experiencing issues. 

Why Would a Furnace Run Constantly?

The most common reasons for a continuously running furnace include:

  • Incorrect Thermostat Settings: If the thermostat is set too high, the furnace may run constantly in an attempt to reach the elevated temperature. Verify that the thermostat is set to the desired temperature and that it’s functioning correctly. 
  • Clogged Air Filters: Dirty or clogged air filters can restrict airflow, making it difficult for the furnace to reach the desired temperature. When this happens, the furnace may run continuously as it struggles to heat your home. 
  • Leaky Ducts: Leaky or poorly insulated ductwork can lead to heat loss, forcing the furnace to work for longer periods of time to meet and maintain the set temperature. 
  • Thermostat Malfunction: A malfunctioning thermostat can send incorrect signals to the furnace, causing it to run continuously. Check if your thermostat is calibrated correctly and consider having it inspected or replaced if necessary.
  • Undersized Furnace: If your furnace is undersized for your home’s heating needs, it may run constantly to try to keep up with the demand. In this case, upgrading to a properly sized furnace may be necessary to achieve efficient heating.

How to Fix a Constantly Running Furnace

A couple issues that can cause a furnace to run constantly can be easily solved with a couple of tweaks. Fixing thermostat settings or replacing a dirty filter, for example, can be done without the help of a professional.

However, larger issues, like leaky air ducts or an undersized system, require the attention of an expert. Sealing ductwork or replacing the furnace is a big project that requires specialized knowledge and experience. Be sure to schedule an appointment for a proper furnace diagnosis and solution if your furnace is running continuously. 

Prevent Future Furnace Issues With Maintenance

While some furnace issues can occur due to normal seasonal wear, others can be completely prevented by scheduling regular, routine maintenance. Furnace maintenance can provide a number of benefits, including:

  • Longer system lifespan
  • Increased productivity and efficiency
  • Fewer system breakdowns
  • Lower energy costs

Contact Evergreen for Furnace Services in Waco, TX

At Evergreen Heating and Air, we’re passionate about helping Waco residents keep their homes safe and comfortable throughout the long winter months. For furnace repair, installation, and maintenance services throughout Waco, TX, and the surrounding areas, turn to Evergreen today.

If your furnace is constantly running, count on Evergreen to deliver a fast, effective, and reliable solution. 

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401 S 13th St,
Waco, TX 76706





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