Chris Harris

Chris Harris

Tech Tips written:

It Has a Flat For a Reason
When tightening down a blower wheel or a fan blade on a motor shaft, ONLY tighten it on the flat of the shaft. That flat is machined into the shaft on purpose. It gives the set screw a face to bite into instead of a curve to slide off of. On most residential motors, it […]
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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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Podcast guest:

Committing to HVACR Education w/ Copeland
 This podcast episode focuses on the critical shortage of HVACR technicians and installers across the industry. The hosts discuss the massive gap that exists, with estimates of nearly 200,000 open roles expected in the next few years. They are joined by Lenny Diaddario from Copeland’s contractor services department and Chris Harris from the educational […]
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