Have you heard the term 'dry-ship R-22 unit' yet? No? Well, let me tell you a dirty little secret of the EPA and the HVAC industry. It involves the environment, the costs that homeowners pay to buy and maintain air…
Apparently, I haven't written a single article this summer about oversized air conditioners. Shame on me! I've written several in previous summers, mostly about how HVAC contractors bypass the HVAC design process by using rules of thumb and how they…
This is the story of a happy family that got too hot and sweaty. They'd lived in their house for a while, and everything was fine at first. The central air conditioning system kept them nice and cool. Over the…
Mini-split heat pumps and ductless go together like peanut butter and jelly. Or do they? If all mini-splits were ductless, then why were those rigid elbows sitting on a jobsite I visited recently? That home is going to be heated…
You've heard of mini-split heat pumps, haven't you? That term often has the word 'ductless' in front of it because most mini-splits have no ducts. There's just the 'head,' which contains the evaporator coil and blower and is usually mounted…
Rod had a major duct failure going on in his crawl space. It was summertime when I visited and took the photos you see in this article, and the ducts had four serious problems that robbed his air conditioner of…
Last month, the Today Show ran a little sting to see if HVAC contractors would do the right thing when brought to a home to diagnose an air conditioner problem that they'd set up. As it turned out, 6 out…
One talk at the 2012 Building Science Summer Camp stood out above all the others. The last speaker on Tuesday was Henry Gifford. (Yes, that Henry Gifford!) When he was done, the majority of the audience stood and applauded. The…
We went through a record-setting heat wave recently in the US. Here in Atlanta, we set an all-time record of 106° F. Homes with properly-sized air conditioners—yeah, yeah, I know they're few and far between—are sized for our design temperature…
Heating, ventilating, and air conditioning (HVAC) systems have undergone great development since our cavemen ancestors huddled around the fire in winter and fanned themselves with palmetto leaves in summer. The rapid development of efficiency and performance experienced by other industries,…