I see a lot of techs and installers use tape over foam tubing insulation joints (Rubbatex, Armaflex, etc.) rather than using the glue that is designed for it. Some of them use tape because they don't know the glue exists; some use tape because it's what they happen to have on the truck, and others […]

I have been teaching at my local trade school as an HVAC instructor for the past year. It’s been a much different experience than training a technician on the job. Some of the students are already working in the field, and others have never been in an attic or crawl space. But regardless of experience […]

Why is it called single-phase 240 when there are two opposing phases (or legs)? I wondered why we called two 120v opposing legs “single-phase 240” for years. Then someone pointed out to me that a typical “single-phase” pole transformer only has one power leg entering and two coming out. That freaked me out. How can […]