Over the years, I have heard technicians say that refrigerant can wear out or “lose its blend” by sitting in a tank. Refrigerant does not wear out or “lose its blend”… at least not like that. What can and does happen is called “fractionation.” Refrigerant blends are composed of a mix of refrigerants with different […]

This article is based on HVAC School’s special video for 100k subscribers. The episode features Eric Mele, Andrew Greaves, and Sam Behncke as special guests. To celebrate HVAC School’s 100,000 YouTube subscribers milestone, we've released a video on a topic that applies to all sorts of HVAC techs. Customers don’t like making callbacks, and we […]

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 […]