Joe Shearer

Joe Shearer

Tech Tips written:

Motor Speed – The Basics
How does a typical single-phase motor know how fast to run? Typical induction motors depend on the electrical cycle rate of the incoming power (measured in hertz) for their speed. Our power in the US makes one complete rotation from positive electrical peak to positive peak 60 times per second, or 60hz (50hz, or 50 […]
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Understanding Relays With the 90-340
Relays can be used for many different control applications, including controlling fans, blowers, other relays, contactors, valves, dampers, pumps, and much more. A 90-340 is a very common, versatile relay that many techs have on their truck, so we will use it as an example. A relay is just a remotely controlled switch that opens […]
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Heat Doesn’t Rise
We’ve all heard some version of the phrase “heat rises,” but is that really true? First, we need to remember that heat is energy, not matter. Heat is a force, not a thing. While heat may result in changes to matter (stuff), it isn’t matter itself. When we add heat to stuff, the molecules inside […]
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Video guest:

Podcast guest:

Expansion Valves – What Does and Doesn’t Matter?
   This podcast features a lively discussion on expansion valves, particularly thermostatic expansion valves (TXVs or TEVs), with a panel of expert guests – Corey Cruz (a market refrigeration tech), Matthew Taylor (head of refrigeration service at Kalos), and Joe Shearer (with Precision Air Conditioning). The conversation kicks off by busting some common myths […]
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Non-Condensibles
Eric Mele and Joe Shearer join Bryan to discuss the challenging issue of diagnosing and rectifying non-condensibles in the circuit. Non-condensibles are gases that don’t condense, including nitrogen. These are NOT moisture or contaminants, and they can be tricky to diagnose; the pressure readings will likely be normal, but the charge will actually be quite […]
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