Home » HVAC Motor Failure – Is Airflow To Blame? Assessing HVAC Equipment Problems

Hvac Motor Failure

HVAC Motor Failure – Is Airflow To Blame? Assessing HVAC Equipment Problems

Although HVAC equipment issues are often blamed on faulty motors, the motor is often not the cause of the problem. As an HVAC parts distributor, CE has the experience and HVAC supplies online to restore comfort and efficiency to your customers’ homes.

Motor Models

The first step in diagnosing motor failure is to determine whether you use a PSC or ECM motor. PSC, or permanent-split capacitor, motors create electrical phase shifts with a capacitor that is not polarized. ECMs, or electronically-communicated motors, use an electronic control module to power a brushless permanent magnet motor. In general, ECM motors are more precise and energy-efficient, resulting in greater use among HVAC equipment.

Determining your motor type lets us assess the conditions necessary for your HVAC parts and supplies to function properly. We can then understand and solve the root cause of the damage. If the motor itself is broken, we must replace it with another motor of the same type. Combining a PSC motor with HVAC equipment designed for ECM motors is technically possible, but will violate the HVAC equipment’s regulatory licensing.

Common Causes

Although a motor replacement is sometimes necessary, HVAC equipment problems are more often due to insufficient airflow. According to a 2010 study, more than three-fifths of the problems we encounter are the result of improper ducting design and installation. Undersized ducting results in high static pressure. If the pressure climbs above 0.65’’ wc, it will cause the ECM motor module’s wattage to double. Not only does this draw excess energy and increase your electric bill, but it will wear the motor down more quickly, reducing the motor’s lifespan.

  • Airflow issues create a variety of secondary problems, including:
  • Cold and hot spots throughout your home
  • Refrigerant charge issues
  • Failed heat exchangers and compressors
  • Sweating on grilles and ducts
  • Suction lines flooded with refrigerants
  • Inefficient use of electricity, leading to higher gas and electric charges
  • Excessive levels of vibration

As an experienced HVAC parts distributor, we know how to select the right HVAC equipment, parts and supplies to keep these issues to a minimum. For more information on assessing motors, restoring airflow, and obtaining HVAC supplies online, contact CE today.


    • Richard Gambaro says:

      Good article but I would correct you on one thing. It is not a communicated motor, it is a commutated motor.

      ECM = Electronically Commutated Motor
      It is the commutation feature that gives the motor its three phase DC Voltage alternating sine wave.

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