Furnaces

Furnace Motor Replacement: ECM or PSC

Furnace Motor Replacement: ECM or PSC

If you're replacing a heating system with a standard blower motor, it's worthwhile investigating different furnace motor replacement options such as an electronically commutated motor (ECM). Here's a look at how standard permanent split capacitor motors compare to more technologically-advanced ECM motors.

Permanent Split Capacitor Motors (PSC)

Standard PSC motors have just two operating modes: off and on. When signaled by the thermostat, these single-speed motors start up and run on high, then cycle off when the temperature setting is reached.

Electronically Commutated Motors (ECM)

An ECM motor can vary its speed in response to changes in your home's heating needs. The motor cycles on slowly and runs for longer periods on the lowest speed necessary to maintain comfort. When more warm air output is needed, it speeds automatically.

PSC Vs. ECM Motors

Here are some additional factors to consider so you can compare how PSC and ECM motors perform and make a more informed decision on which type is the best choice for your home:

  • Energy consumption. A furnace blower unit equipped with a variable-speed ECM motor uses up to 75 percent less electricity than a blower that's powered by a PSC motor.

  • Maintenance needs. An ECM motor has "true" bearings that don't need lubrication, it starts, ramps up and stops "softly" and runs on low speed most of the time. Because an ECM motor is under less strain and subject to less wear than a PSC unit, it requires less maintenance.

  • Temperature control. With its longer cycling and variable-speed operation, an ECM motor can provide more consistent temperatures and better humidity control than a one-speed PSC unit that cycles on and off frequently.

  • Equipment lifespan. ECM motors have an expected lifespan of about 90,000 hours, compared to PSC motors that typically last for 40,000–50,000 hours.

  • Air filtration. The prolonged cycling of an ECM motor also means that the indoor air gets pulled through the furnace filter more often, so it's able to remove more debris from your air supply.

To learn more about different furnace motor replacement options for your Broken Arrow home, contact us at Air Assurance.

Our goal is to help educate our customers in the Tulsa and Broken Arrow, Oklahoma area about energy and home comfort issues (specific to HVAC systems). For more information about motor replacement and other HVAC topics, call us at 918-217-8273. Credit/Copyright Attribution: “feng-yu/Shutterstock”