Static pressure is the airflow resistance in the ductwork. Standard air pressure is essential since too little or too high pressure will cause energy inefficiency and system failure. The homeowner or premises manager must understand the static pressure concept, but the professional HVAC must.

The fan doesn’t have to work out of its designed settings if the duct system is installed correctly. However, if the duct system is improperly installed, the fan will work harder outside its parameters.

How Static Pressure Occurs

To fully understand static pressure consider water flowing through a hose; if you impede the flow of water by placing a finger and the tip of the hose and changing the diameter of the hose, static pressure will increase. Water acts the same as air, so shrinking duct holes will improve the air’s speed. Most duct fans are rated for static pressure of 0.5 WC. The higher the static pressure, the higher the noise and vibration.

How Static Pressure Affects the System

High static pressure causes a noisier blower as the motor is forced to work harder, like a jet engine. On the other hand, if there is insufficient airflow, you might end up with hot or cold spots in the house. Your energy bills will rise as the systems will be forced to run longer since inadequate heat or cool air is blowing out of the vents.

Effects of static pressure:

• Leaking ducts
• HVAC systems running longer
• Noisy operation
• Parts of the systems wearing out faster

Fixing the Static Pressure Problem

Static pressure is mainly caused by poorly designed ductwork. You must address the supply side of the air or the inadequate return coming to the furnace. Hence building additional ductwork that provides more airflow to the room will provide sufficient air. Also, check the filters that might be clogged by dirt restricting return air, which will make the motor work harder.

Contact Shield Comfort Heating & Cooling for HVAC ductwork. We understand the ideal static pressure for your HVAC system that matches your needs. We serve Avon and the surrounding areas and provide everything from heat pumps and dryer vent cleaning to duct cleaning and indoor air quality checks. Contact us today!

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