Duct Air Leak Test Procedure

First you need to determine if a duct leakage test is required.

Duct air leak test procedure.

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

The basic idea behind using a duct leakage tester to test for duct leakage is. 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. Another form of duct leakage to outside uses a blower door to measure the total amount of.

Leakage class can be calculated using equation 3 but needs to be specified if duct air leakage tests are required. A third test method. 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. 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.

Test apparatustest apparatus duct leakage test system consists of duct leakage test system consists of. 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. 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. This includes areas like unconditioned attics garages and crawlspaces.

The above test procedure describes how to determine total duct leakage or how much leakage there is. To find the total duct leakage that s basically all you do. For more information see the real zero guide to the 13 most common leaks. Use the line tap to access the system to diagnose problem.

Potential accuracy of flow measurements should be evaluated. Conduct multi zone pressurization leakage test. 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. Use a calibrated fan to pressurize the duct system.