With increasing numbers of customers making green and energy-efficient decisions, it’s becoming even more important for HVAC contractors to pay attention to their customers’ air quality. “Adequate fresh air should be an equal priority to energy savings,” said Allen Rathey, president of the Healthy House Institute (HHI).

When we last visited with lead installer John and his helper Charlie, they had learned how to measure external static pressure on a new system. They were shocked to measure a high 0.98 inches of water column - and surprised when their trainer asserted the airflow through the unit was probably OK.

Measuring duct static pressure is a fundamental part of diagnosing how a duct system is performing. It’s kind of like getting your blood pressure tested when you go to the doctor.

John Logue was stumped. The contractor designs and installs 55 to 80 HVAC systems a year, but he had never run into this situation - a customer complaining that water was coming out of the homeowner's supply grilles.

Many building codes in the southeastern United States call for increased attic and crawl space ventilation to fight moisture and related IAQ problems. Craig DeWitt, Ph.D., P.E., challenged that notion at the South Carolina Association of Heating and Air Conditioning Contractors' (SCAHACC's) 2003 Indoor Comfort Science Conference.

Sometimes it's all in the tools you use.