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 […]

I don't do much in the way of “rack” refrigeration. However, I recently had a conversation with experienced rack refrigeration tech Jeremy Smith, and he got me thinking about EPR valves. I've heard EPR (evaporator pressure regulator) valves called suction regulators or hold back valves. In essence, they hold back against the suction line to […]

The Sleeper  The year was 2002, and I was 20 years old. I had a helper named Clay, and he was a really nice guy, probably 15 years my senior, already with streaks of grey in his hair with a way of making you feel at ease—so very at ease. OK, he was sleeping most […]