Heating, ventilation and cooling (HVAC) systems leverage fans to circulate air throughout the homes and buildings in which they are installed. From the moment your HVAC system turns on, a fan will begin to blow air throughout your home. High static pressure, though, may hinder its ability to circulate fan. The fan may still spin, but it won’t be able to perform its intended function with high static pressure.

What is Static Pressure?

Static pressure is a measurement of airflow resistance. It represents the amount of force or pressure a fan needs to generate to circulate air. Low static pressure means the fan needs to generate a minimal amount of pressure to circulate air. High static pressure, conversely, means the fan needs to generate more pressure to circulate air.

HVAC technicians measure static pressure using a device known as a manometer. Some manometers feature transducers, whereas others feature a tube of liquid. Using a manometer, HVAC technicians can determine how much pressure a fan needs to generate to circulate air.

How Static Pressure Affects Your HVAC System

Now that you know the definition of static pressure, you might be wondering how it affects your HVAC system. Low static pressure isn’t a concern. With low static pressure, the fan will be able to easily push – as well as pull – air throughout your home. But high static pressure can lead to other problems.

You may notice hot and cold spots in your home with high static pressure. Static pressure represents how much work your HVAC system’s fan must perform to circulate air. If it’s too high, the fan may struggle to circulate air. It may blow conditioned air into some rooms but not others. Any room that receives little or no conditioned air will suffer from hot or cold spots.

Your HVAC system may require more frequent maintenance with high static pressure. It will strain many of your HVAC system’s parts, including the fan and compressor. When left unchecked, these parts may fail. To protect your HVAC system from premature failure, you need to ensure that the static pressure is low.

High static pressure will make your HVAC system less efficient. Fans consume energy. With high static pressure, the fan will have to run for a longer period. Whether you’re trying to cool or warm your home, high static pressure will make your HVAC system less efficient.