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A/C Duct Tests

A/C Duct


An A/C duct test is another energy test for a home, where a small duct blaster fan is installed to the main return of the a/c system, along with covers placed on all supply and returns. Then a negative or positive pressure of 25 pascals is placed on the duct work, and calculated out. Once the calculation is done, the energy auditor can determine how loose or tight the duct work is.

The best time to perform a test is before drywall is installed, however the test can be performed after completion of home as well.

Some building departments require this test before issuing a Certificate of Occupancy. If the duct work is in conditioned attic space a duct test is not required.

In some cases, air losses of 20-30% can occur before air enters through supply grills, in turn, increasing energy bills and discomfort in the home. Pressure buildup in unconditioned space can also promote mold growth, and create more air leakage in the home. Also, air conditioners running constantly can be a sign that you may need a duct leakage test performed. 

Information provided by the U.S. Energy Information Administration in 2015, tells us that the average American household uses roughly 50 percent of its energy for heating and/or cooling. Duct leakage helps to make up for 20 % of annual energy costs. This does not even account for air losses from the drywall envelope which can add an additional 25-40% to heating and cooling costs.

Furthermore, a leaky system can shorten the life of your air handler and condensing unit, costing a homeowner thousands in replacement and repair costs in shorter spans. 

If you're thinking about getting a duct test done, please don't hesitate to give us a call!


How it Works

By pressurizing a homes duct work to 25 pascals, the machine is able to determine the amount of air leakage in the A/C system. Usual problems of poor workmanship can fortunately be quickly remedied typically with tape and mastic. 

Frequently Asked Questions
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