All fuel-burning appliances require oxygen to burn. They require sufficient oxygen to burn clean and safely, without soot and CO (carbon monoxide). I live and work in Florida, where most of our fuel-burning appliances are 80% efficient with open combustion. (You can learn more about the basics of combustion on a podcast with Benoit Mongeau.) […]

I was fresh out of school, working as an apprentice at my first real HVAC job, and I was listening in on a shop conversation between a few techs. They were talking about finding so many overcharged systems. One of the techs turns to me and says, “I had a unit yesterday that was so […]

A while back, I had a tech who was having some trouble finding a 35 PSI (2.41 bar) make-on-fall pressure switch. One adjustable switch in the catalog said (SPDT), but he didn't quite understand what that meant. In that case, it means single-pole, double-throw, and the “double-throw” part means that the switch has terminals in both the […]