When I first started in the trade, I used to advise customers with hot attics to install powered attic ventilators (PAVs) to “suck” that hot air out of the attic. It just made sense to me at the time; if the attic is hot, get the hot out! When I started learning more about design, […]

This article was written by Christopher Stephens. He is a commercial HVAC/R service manager in the greater Los Angeles area. Thanks, Chris. Let’s start by covering the three elements needed for a fire: fuel, air, and heat (spark). With those three elements in the right condition, you can start a fire. So, if we reduce […]

When I first started in the trade, we used to run into shielded control wires on the Carrier Comfort Zone 1 zoning systems and also on a Carrier VVT system I used to maintain at a bank. I knew it has something to do with electrical “noise” and that communicating systems often called for it, […]