Service & TroubleshootingQuestion 91 of 110
An ECM (electronically commutated motor) blower offers what advantage over a standard PSC motor?
a.It requires no electricity
b.Variable speed operation and improved energy efficiency
c.It eliminates the need for ductwork
d.It removes refrigerant charge
Explanation
ECM blower motors can vary speed to maintain target airflow across changing static pressure and generally use less energy than fixed-speed PSC motors. This improves comfort and efficiency and supports California energy goals. They are diagnosed differently, often through control signals and modules.
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