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 […]

Enthalpy is easy. It's just a state function that depends only on the prevailing equilibrium state identified by the system's internal energy, pressure, and volume. It is an extensive quantity. Simple. Like most things, the scientific definition is as clear as mud. In HVAC/R, we use enthalpy measurement to come up with the total heat […]

This article was written by senior furnace tech Benoît (Ben) Mongeau. Ben hails from the frozen tundra of Ontario, Canada, where high-efficiency gas furnaces are commonplace. While some codes and practices may be different from the US, I find that most of it is common sense and translates pretty well. One glaring difference between Canada […]