Making sure your home has tight ducts also makes sure that warm, energy-efficient comfort reaches all rooms in the house this winter. Most residential ductwork doesn’t last as long as the house where it’s installed. Over time, air leaks develop at loosening joints and/or rust or corrosion occurs. In the typical home, the U.S. Department Of Energy estimates that at least 20 percent of heated or cooled air never reaches the rooms it’s supposed to keep comfortable. Instead, this conditioned air — along with the money you spend for heating and cooling costs — is lost through duct leakage into the attic, crawl space or the inside of wall voids.
Since most ductwork in the house is inaccessible to the average homeowner, how do you tell if your home has leaky, energy-wasting ducts? Only an inspection and pressure test by a qualified HVAC contractor can reveal the truth about what’s happening inside the dark recesses of your ductwork. Here’s what’s involved.
- A complete visual inspection of the entire span of household ductwork, inside and out, will give your contractor an accurate assessment of the system’s physical status. He’ll look for telltale signs of air leakage and rust or corrosion. Any segments of collapsed ductwork or kinked flexible duct will also be noted, as will other factors like contamination by moisture or presence of insects or vermin.
- After the visual checkup, the contractor will perform a pressure test to establish the exact extent of leakage. After closing all the vents, he or she will place pressure sensors inside the ductwork and utilize a blower fan to lightly pressurize the ductwork. A computer keeps track of the amount of air volume required to maintain pressure in the ducts and calculates that finding into a percentage that expresses the amount of air leakage relative to total airflow.
- If the numbers indicate leakage above recommended levels (in many locales, maximum allowable leakage is prescribed by local codes) the contractor can discuss duct repair and sealing options to restore proper airflow.
For more on keeping your home comfortable and efficient with tight ductwork, contact Davis Air Conditioning.
Our goal is to help educate our customers in the Lawton and Duncan, Oklahoma area about energy and home comfort issues (specific to HVAC systems).
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