Pump down solenoid valves are commonplace for any refrigeration technician. They are energized with the compressor still running, shutting off flow in the liquid line so that the refrigerant is pumped into the condenser and receiver. The compressor will then shut off once a low-pressure switch opens the circuit when the pressure falls below a […]

As we have mentioned in several previous articles (such as this one HERE), many blended refrigerants have glide, which simply means they boil and condense over a range of temperatures instead of just one temperature. As an example, consider refrigerant R407c. It is a zeotropic blend, which means it has enough glide to make a […]

This article is written by longtime tech Shaun McCann sharing his experiences with a big problem in our trade. Thanks for this, Shaun.  I started in the HVAC business working for a small commercial union shop in the late '80s. I left that job within a year and worked in the bar and restaurant business […]