This tech tip comes from our contributor, compressor decapitator, and super tech Ulises Palacios. Many ductless systems and some high-efficiency unitary systems have electronic expansion valves. If you find one that is stuck closed, you may be able to get it open temporarily by putting a strong magnet like the one shown above on the […]

First, let's get something straight: BRAZING is when you use a filler rod that isn't the same material as the base metal but melts ABOVE 840°F. Soldering is the same but at temperatures BELOW 840°F. With HVAC rods melting at around 1200°F, it confuses me why we usually call it “silver solder” but also often call it […]

It’s that time of year again—the furnace service calls are peaking. It’s a good idea to crack open Jason Obrzut’s book, Gas Heating: Furnaces, Boilers, Controls, Components, and listen to the many public podcasts and presentations by experts like Jim Bergmann. At HVAC School, we’re fortunate to have had some of the industry’s greatest minds […]