Replacing a Furnace Motor: Deciding Between ECM and PSCFacing a furnace motor replacement may not seem like it would make much difference in home comfort, but if you upgrade it with an ECM (electronically commutated motor), you’ll have plenty of reasons to be glad you did. Most furnaces and air conditioners use PSC (permanent split capacitor) motors for the blower, and while they’re durable, they’re limited in other ways.

How They Work

A PSC motor runs on high speed only. When the HVAC system turns on, the blower motor starts distributing the conditioned air and it stops the moment the thermostat reaches the temperature setting.

ECMs use advanced circuitry that controls how fast they run. They start the heating cycle slowly, speed up when it reaches mid-cycle, and slowly ramp down before they stop.

Comfort Advantages of an ECM

  • Increased indoor comfort. A system that uses an ECM runs longer at lower speeds that give it more time to circulate the conditioned air. Rooms that were otherwise uncomfortable will have time to heat or cool.
  • Reduced noise levels. ECMs start slowly, minimizing the sudden onset of noise in rooms closer to the blower compartment. The gradual increase in running speed isn’t as noticeable as the noise a PSC motor makes when it runs.
  • Better humidity removal. Selecting an ECM as a furnace motor replacement increases indoor comfort in the summer because this type of motor increases the amount of humidity the A/C removes.
  • Better air quality. Since the HVAC system runs longer at lower speeds, the air filter removes more airborne particulates, which helps anyone suffering from allergies or asthma breathe easier.

Mechanical Advantages of an ECM

  • Lower energy consumption. ECMs use nearly 80% less electricity than a PSC does.
  • Longer lifetime. The estimated motor life for an ECM is approximately 90,000 hours, compared to 40,000 for a PSC.

Opting for a furnace motor replacement with an ECM offers substantial advantages over the PSC motor. If you’d like to learn more, contact Team Bob’s Heating Cooling Plumbing, providing trusted HVAC services for homeowners in Grand Traverse County and the surrounding areas.

Our goal is to help educate our customers in Traverse City, Michigan and surrounding areas about energy and home comfort issues (specific to HVAC systems). For more information about furnace motors and other HVAC topics, download our free Home Comfort Guide or call us at 231-714-6196.

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