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Blower Control Module

The blower control module is a solid-state device that operates the blower motor. The blower control module outputs a voltage that varies between 0 volts (blower motor OFF) and 12 volts (maximum blower motor speed).

To determine the appropriate output voltage, the blower control module monitors a varying voltage signal (between 2 and 8 volts) from the HVAC programmer. The module then amplifies the signal and applies voltage directly to the blower motor. Blower control module voltage is also monitored by the HVAC programmer.