Residential duct systems leak 20% or more of conditioned air according to some national studies. This means that 20% of cooling capacity, heating capacity, and utility dollars are going into unconditioned space due to air loss alone. Poorly insulated ducts also cause the air inside the ducts to heat up in summer and cool off in winter before the air reaches the living space inside the home increasing utility costs. Duct leaks also cause pressure imbalances inside the home causing indoor air quality problems.
We find many duct systems to be poorly designed and installed. A sure sign of duct a design problems is rooms that heat or cool unevenly. Other duct design problems that result in lower equipment effeciency and poor indoor air quality are not so obvious.
Dust streaks around supply vents are often thought to be caused by a dirty duct system. Most of the time dust streaks around supply vents are caused by leaks in the duct system between the “bucket”, the sheet rock, and the supply vent cover. A venture effect caused by the moving air sucks dirt, humidity and heat directly from the attic. This type of problem is the result of poor duct construction or a duct system that is comming apart.
Poorly insulated points or sections of ducting can cause moisture and microbial growth to occur. Air is then circulated past the molds growing in the duct system, distributing mold spores thru out your home. Since these spores are created after the filter; even the best filtration system can’t fix this kind of indoor air quality problem. In this case the duct sustem is the problem and must be repaired to achieve better IAQ.
Proper duct design is also important in achieving and maintaining proper system operation and efficiency. Many homes have supply air outlets placed near the interior walls of the home. This poor duct installation practice creates a need to run high duct static pressures in order to push air all the way from the interior wall to the exterior wall where the majority of the heat enters your home. This one poor duct design feature creates noise at the vents, excesssive static pressure inside the duct, and a host of potential problems.
Consult an AirOne® technician about the potential duct problems in your home. They have the knowledge and experience to help you do what is best for you and your home … call 512-392-0022