How to Test Your Cold Air Return Ductwork | Direct Energy Blog

How to Test Your Cold Air Return Ductwork

When most homeowners think about their ductwork, they concentrate on how much hot or cool air is blowing out. Many have spent a lot of time sealing and insulating the ductwork leading away from the HVAC blower, thinking that is all they need to do improve their system’s efficiency. Unfortunately, they are only half done.

Why is Sealing Ductwork Important?

The cold air return ductwork is as important to your home’s heating and air conditioning as the lines coming out. While insulating the cold air return might not be important, sealing it is, for two reasons. One is that you want air recycled from the rooms you are heating or cooling. This way, they don’t feel stuffy and are easier to heat or cool. Let’s say you have crawl space under your home where some of the return ductwork passes through. If there is a break in that return ductwork, it could suck up mold, mildew, fungus, and moisture and pass all that into your home. Not only will it make your HVAC system work harder, it could also make you or your family members sick. Sealing the return ductwork helps keep the air in your home clean and breathable.

Improved Efficiency

The other reason is that by sealing both the outflow and return ductwork, you improve the efficiency in circulating air through your home. Your blower motor will not need to work as hard or run as hot. Most importantly, it will take less energy to heat or cool the air in your home because it will be running in a more tightly closed loop. By running more efficiently, especially during this hot summer, you’ll pay a lot less to keep your home comfortable.

Test Your System

So how well does your ductwork suck? Try this simple test when your HVAC system is running: get a piece of tissue paper and dangle it about six inches from one of the return vents. You should be able to see it being gently pulled towards the vent. Next, place it up against return vent and see if the air suction holds it in place. If the tissue is held firmly in place, your return ductwork has adequate sealing. If the tissue slides or falls off, there’s probably a hole or blockage somewhere.

By sealing your HVAC ductwork at both the blown and return lines, you can save money and improve your home’s comfort.

Related Posts

About 

Vernon Trollinger is a writer with a background in home improvement, electronics, fiction writing, and archaeology. He now writes about green energy technology, home energy efficiency, the natural gas industry, and the electrical grid.