Compressors and Pumps
Let’s go with dictionary definitions of each one first. pump noun 1. A mechanical device using suction or pressure to raise or move liquids, compress gases, or force air into inflatable objects such as tires. compressor noun 1. an instrument or device for compressing something. Both compressors and pumps move fluids, and a fluid: Yields or […]
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Liquid Line Solenoid Valves: Long Line Applications
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 […]
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The Ductless Dehumidification Conundrum
This tech tip was a COMMENT on a Facebook question about how ductless systems achieve some of their high-efficiency numbers at the expense of dehumidification. This was the question: Bryan Orr mentioned that multi-stage mini splits often do very little latent cooling (dehumidification) because on low speed the manufacturers all “let the evaporator float, which […]
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Trades and the Skills Gap – A Manifesto
This article is a year old, and I’m recycling it because it’s on my mind today. I had a fun conversation with Richard Trethewey on the podcast that has me thinking along these lines today. The link is HERE if the player isn’t showing up. I have a confession to make. I’m a bit of […]
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Using Power Factor to Check Capacitors Under Load
Capacitors are traditionally tested with a capacitance meter (commonly found as a function within a multimeter), with the component taken entirely out of the circuit. “Bench testing,” as this method is referred to, is hands-down the safest method of checking capacitance in microfarads. All other methods require the capacitor to be wired into the circuit […]
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Checking the Charge on a Heat Pump in the Winter
When you ask many people nowadays how to check the charge on a heat pump during low outdoor temps, they will say that you need to “weigh in and weigh out” the charge. While this may be an effective method, it isn’t always practical. Now, if you are making a refrigerant circuit repair, weighing out […]
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The Learning Mindset – Trial & Error
I’m far from a country boy, but I did grow up in a rural area with animals, playing in the woods, and cleaning out chicken coops. Like many of you, we would play most of the day outside without our parents knowing or worrying about where we were. Was that an “unsafe” way to grow […]
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The Learning Mindset – It Isn’t Obvious Until It Is
Note: This short series is on the mindset of learning (and teaching), not really a “tech tip,” per se. We will be back to the tech tips in a few days.  I’ve heard and repeated these phrases countless times over the years, both at home and work: That should be obvious. It’s just common sense. […]
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Balanced Port TXV
  I walked into a supply house the other day and looked at a “universal” expansion valve on the shelf. The friendly guy behind the counter saw me and walked over. After saying hello, he said: “That’s a great valve; it’s even balanced port.” Now, I am a bit of a troublemaker. I should have […]
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