This tech tip video comes from my friend Andrew Greaves of AK HVAC and HVAC Comedy on Youtube and the HVAC Vehicle Layouts group on Facebook. Many residential techs get confused when they see these multi-position valves in larger equipment, and Andrew does a great job of demonstrating the basics in this video. In the […]

Air conditioning was about humidity control from the very start. Willis Carrier's very first air conditioning system was all about controlling the humidity with the side effect that it also could reduce the sensible temperature. Theaters caught on that this newfangled contraption could lead to big summer numbers when they installed it to keep patrons […]

I recently received a message asking for a discussion of relative humidity (RH), wet-bulb (WB), and dry-bulb (DB). Time and time again, I hear techs say that condensation occurs when “hot meets cold,” which may be true in some cases. However, that is only a shorthand way to describe it and doesn't really address what […]