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The Future, Energy Efficiency

Duct work testing

Duct Testing

A duct leakage performance test involves pressurizing or depressurizing the duct system with a calibrated fan and simultaneously measuring the air flow through the fan and its effect on the pressure within the duct system. The tighter the duct system, the less air you need from the fan to create a change in duct system pressure. Testing procedures can be set up to measure only duct leaks which are connected to the outside, or to measure total duct leakage (i.e. leaks connected to the outside and inside of the house). Duct leakage measurements are used to diagnose and demonstrate leakage problems, estimate efficiency losses from duct leakage, and certify the quality of duct system installation.

Duct Work Testing

A Duct Testing Fan System is used to directly pressure test the duct system for air leaks, much the same way a plumber pressure tests water pipes for leaks. The Duct Testing fan is first connected to the duct system at the air handler cabinet, or a return grille. After temporarily sealing all remaining registers and grills, the Duct Testing fan is turned on to force air through all holes and cracks in the ductwork. The fan speed is increased until a standard test pressure is achieved in the duct system. A precise leakage measurement is then made using an airflow and pressure gauge connected to the Duct Testing system. Estimates of efficiency losses from duct leakage can then be made from the leakage measurements.

A theatrical fog machine can be used along with the Duct Testing fan to inject a non-toxic fog into the duct system to visually demonstrate the location and extent of leakage in the ductwork.