The Difference Between Variable-Speed and X13 Motors
First, let's cover the basics. X13 is a brand name for the Regal Beloit/Genteq brand of constant torque motors; there are other manufacturers that make them, but the term “X13” has become pretty much synonymous with the fractional horsepower HVAC constant torque motor. Also, this article specifically discusses common residential/light commercial motors. There are other […]
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Diagnosing ECM & X13 Motors
First, let's give proper credit. Most of the best practices and tools for diagnosing ECM and X13 motors come from Regal/Genteq and their site, thedealertoolbox.com, and their app, The Dealer Toolbelt (available on the App Store and Google Play). Your best bet is to follow the practices shown there and use their TECInspect diagnostic tool […]
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Capacitor Testing and Replacement Procedure
❶ Understand What a Run Capacitor Does The run capacitor provides continuous phase-shifted current to the motor start winding, allowing the motor to run: With the design efficiency In the right direction With the appropriate torque With near “unity” power factor (power factor near 1.0) If the run capacitor is failed, the motor often won't […]
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Potential for Good and Evil (The Hard Start & Potential Relay)
I have spent most of my career being afraid of hard start kits; I heard too many horror stories of start caps exploding and sales technicians telling every customer they need one. It dawned on me recently that it may be time for me to take a more mature look at start capacitors, potential relays, […]
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Motor Speed – The Basics
How does a typical single phase motor know how fast to run? Typical induction motors are dependent of the electrical cycle rate of the entering 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 […]
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Tech Question – Why Do ECM Motors Trip a GFCI?
This question was submitted on the site in response to the recent GFCI tip. It's a good question with several possible answers. What do you think? Hey Bryan, I have had a few instances where we are firing off a furnace in a new build with a temporary power pole outside with gfci outlets installed […]
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Aftermarket Motor Selection & Considerations
This article was written by technician and HVAC School community star Kenneth Casebier. Thanks, Kenneth! When looking at replacing a single-phase A/C motor with an aftermarket motor from your van, there are a few things you should know and pay attention to. First, the factory OEM motor will always be the best option, especially when […]
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HP, Motor HP, BHP, Motor Watts
Brake horsepower (BHP), motor nameplate HP, and the actual electrical power (watts) a motor will consume are different but related concepts. They can get confusing. So, we will tackle them one at a time. Let us start with simple definitions of work, power, and horsepower. Work = distance in feet x force in pounds, both […]
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Motor Types
In residential and light commercial HVAC, we work primarily with PSC (permanent split capacitor) motors. However, it is good to be aware of some other types. PSC (Permanent Split Capacitor) A common medium torque single phase motor with a run capacitor always in the circuit. This type makes up the majority of HVAC motors (condenser […]
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