Crankcase Heaters and Single-Pole Contactors
We keep two-pole, 40-amp 24v coil contactors on all of our vans. They are versatile and reliable, and you can replace most residential A/C contactors with them. There are a few things to watch for, though, especially when you have a crankcase heater. Many brands power the crankcase heater constantly and shut it on and […]
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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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Compressor Performance Analysis
This article is written by a regular contributor, experienced rack refrigeration tech, and RSES CM Jeremy Smith. Thanks, Jeremy. Also, there is a podcast out about what kills compressors HERE. A technique that you can use to diagnose compressor problems and help differentiate them from other possible issues is compressor performance analysis. Manufacturers do extensive […]
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Ever Hear of Copper Plating Inside the Compressor?
First off, I want to thank Ulises Palacios for taking these photos. He is in the habit of cutting open the compressors he replaces to see why they failed (when possible). I think that’s pretty boss. So, why would the compressor have copper plating on the inside? They certainly aren’t manufactured that way. The short […]
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Commercial Refrigeration Compressor Operation
Basic Compressor Functions The compressor’s job is to circulate refrigerant through the system by means of vapor compression, similar to the way your heart moves blood through your circulatory system. Refrigerant circulation is measured in lbs/min or lbs/hour; this is called mass flow rate—the mass flow rate changes depending on the density of the refrigerant […]
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The Dangers of the “Diesel Effect” (Compressor Explosion)
My friend Ami Slavin requested that I write about this important topic in response to the horrifying videos showing up online of death and gore associated with compressors exploding. He pointed out that the “diesel effect” can be the cause, so let’s explore what may be—and likely is—leading to these horrible incidents. In a diesel […]
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