Loose duct connections or poor sealing results in air loss and air quality issues. These can be repaired by identifying the leaks during an air leakage test, and subsequently patching the connection.
As well, un-insulated ducts can contribute to energy loss and increased condensation and mold growth. Return leaks can draw in polluted air from the attic or crawl space and cause condensation or lead to mold growth.
Pinched, crushed or broken duct work, as well as clogged filters, are also common problems leading to HVAC inefficiency. When possible, technicians will improve the duct system by using less turns and configurations to reduce air flow friction.
Most noticeably, supply leaks can depressurize areas and cause back-drifting. Imbalanced air supply throughout the dwelling leads to temperature variability and overall discomfort. This is why some rooms become colder or warmer than others.
Duct Leakage Test
A duct leakage performance test involves pressurizing 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. You need less air from the fan to create a change in duct system pressure, the tighter the duct system. Testing can be set up to measure leaks connected to the outside or can be set up to measure leaks connected to the outside and the inside of the house.