Duct Air Leak Test Procedure

Measure the airflow through the fan with the duct system at pressure.

Duct air leak test procedure.

To find the total duct leakage that s basically all you do. Ensure all valves are capped. Additional methods leakage to outside. If any supply or return duct chases flexible lines or air handler units are in these areas by iecc 2015 code a duct leakage test is required.

Another form of duct leakage to outside uses a blower door to measure the total amount of. Use the line tap to access the system to diagnose problem. Test apparatustest apparatus duct leakage test system consists of duct leakage test system consists of. This american national standard ansi smacna 016 2012 covers revised leakage criteria and builds on the proven methods for testing ductwork for air leaks from the first edition.

With all diffusers sealed as in the first test above this new test method simultaneously investigated air leakage through all major pathways from the underfloor plenum including not only leakage to the room but also leakage to the adjacent 6thfloor and to the outside. The only time duct testing is required is when parts of the hvac system are outside of the conditioned envelope. If the system is short of refrigerant decant the remainder of the charge and replace the line tap with a schrader before re processing the system. First you need to determine if a duct leakage test is required.

1 blower with speed control vfd to generate range of pressure flowrange of pressure flow 2 flow measuring devices flow grid flow station high flow flow grid flow station high flow orifice plate low flow. The hvac air duct leakage test manual provides practical and detailed procedures for conducting leakage tests. For more information see the real zero guide to the 13 most common leaks. This includes areas like unconditioned attics garages and crawlspaces.

Contains updates to the expected leakage rates for ductwork constructed to the smacna hvac duct construction standards metal flexible duct leakage test procedures recommendations on use of leakage testing types. A third test method. Leakage class can be calculated using equation 3 but needs to be specified if duct air leakage tests are required. Figure 5 1l from the 2012 smacna hvac air duct leakage test manual shows the allowable leakage as a function of duct leakage classification and static pressure in the duct.

The basic idea behind using a duct leakage tester to test for duct leakage is. Apparent differences of about ten percent between fan delivery and sum of airflow measurements at terminals do not necessarily mean poor sealing and excess leakage. Use a calibrated fan to pressurize the duct system. Total duct leakage test 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.