Total Leakage Duct Pressurization Test

Watch this 5 minute video for a quick look at how to use the tec duct blaster to conduct a total leakage duct pressurization test.

Total leakage duct pressurization test.

Duct leakage measurements of flow requirements problem. Smacna 2012 hvac leakage test manual shows the recommended leakage class. Test pressure higher than duct design. Both the 2009 and 2012 iecc require duct tightness to be verified.

The amount of air flow in cubic feet per minute required to pressurize the ducts to 25 pa of pressure. The only other thing you need to make sure you do is keep the spaces where the ducts are at the same pressure as the outdoors as much as you can anyway. The result of a total duct leakage test is a measurement of cfm25. Leaky ducts will require a higher flow rate to achieve this pressure than tight ducts.

A duct leakage tester is a diagnostic tool designed to measure the airtightness of forced air heating ventilating and air conditioning hvac ductwork. For our example with a seal class of c for the low pressure duc t the leakage would be about 2 cfm. In the previous page on the basic duct leakage testing procedure we said that you pressurize the duct system and measure the airflow through the fan. The fan speed is increased to attain a pressure of 25 pa in the ducts.

To find the total duct leakage that s basically all you do. Total leakage measured with a pressure differential of 0 1 inch w g. If the test is at 6 static pressure for leakage class 3 compliance i e 9 6 cfm per 100 s f with 6 orifice differential and 6 duct test pressure the meter could only indicate 24 cfm. Total leakage measured with a pressure differential of 0 1 inch w g.

Disregards size of ductwork static pressure i e. Thus it is not worth the cost of testing the low pressure duct for leakage. 25 pa across the system including manufacturer s air handler enclosure all registers taped or otherwise sealed post construction test. Verification can take place via either a post construction test or a rough in test for the post construction test leakage measurement must be made across the entire system including the manufacturer s air handler enclosure with all register boots taped or sealed at a test pressure of 0 1 inches w g.

Ducts shall be pressure tested to determine air leakage by either of the following. However the blower for the test apparatus would have to produce 24 cfm at 10 to 12 static.