Circuit/System Description

The HVAC control assembly applies a ground to the blower motor control circuit that corresponds to the selected blower speed. The resistors and the blower motor are in a series circuit. The following list represents the number of resistors in series with the blower motor per particular speed request:

• Low speed, 3 resistors
• Medium 1 speed, 2 resistors
• Medium 2 speed, 1 resistors

When the operator requests high speed, the HVAC control assembly applies ground to the high speed blower relay control circuit. When the relay contacts close, ground is applied directly to the blower motor through the blower motor resistor.