I heard a great presentation by Ron Auvil on VAV systems, and it got me thinking… Can you size a commercial system/perform a block load by the number of occupants? Yes!  No, I'm just kidding. That's crazy talk. There is way more to it than that. However, in a commercial environment, while the building's perimeter […]

Many HVAC/R technicians (including me) describe the compressor as the heart of the refrigeration cycle. It prepares the refrigerant for the condensing process, which is crucial for heat rejection.  However, some refrigeration methods don’t require a compressor. In this article, we’ll look at those methods and their applications.   Gas movement without compressors As you […]

If you are used to simple, straight-cool split systems, you know that the low voltage to the outdoor unit is usually VERY simple. In many cases, there's just a Y (contactor power) and a C (common) connected to the outdoor unit. When the condensing unit controls are strictly two-wire low voltage, there is no continuous […]