Brendan Reid is President of the Comfort Institute (CI), Bellingham, Wash. CI provides building science training and instruments for whole-house and air-distribution diagnostics and repair. He can be reached at 360-420-5049.
If the fact that the latest U.S. Department of Energy (DOE) and Energy Star programs now require a whole-system approach to HVAC installation and maintenance is any indication…
If there’s an indoor mold problem, all authorities agree that the mold needs to be cleaned up. However, mold problems can be traced to moisture problems. No moisture, no mold growth. Identifying and eliminating the underlying moisture source - or other cause of excess humidity - is just as important as mold cleanup. What does this have to do with HVAC? A lot.
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.
In this article, two techs find out that there's more to fixing a duct system than meets the eye. They found this out after a battery of leakage, airflow, and pressure tests were performed on the house and duct system on which they'd just finished working on.
HVAC replacement contractors across the nation are now embracing duct system performance testing and renovation as a value-added service that differentiates them from the 13 SEER pack. Whether you do it voluntarily or are forced into it by code, your company is going to need to get more proficient at selling and delivering duct-repair services.
