Blower Controls

VARIABLE SPEED MOTOR
The Blower Motor is a variable speed motor. The higher the voltage applied to the motor, the faster the speed.

BLOWER MOTOR OFF
With the HVAC Control Assembly in "OFF," voltage is applied to the Blower Motor Low Speed Relay coil. The relay is energized and voltage to the Blower Switch is removed. No voltage is supplied to the Blower Motor.

BLOWER MOTOR RESISTOR
When any other mode except "OFF" is selected, the Blower Motor Low Speed Relay is deenergized and voltage is applied to the Blower Switch and Blower Motor Resistor.

LOW SPEED
When the Blower Switch is in "LO," voltage is applied through the Blower Motor Resistor and the Blower Motor High Speed Relay to the Blower Motor. The Blower Motor runs at low speed.

MEDIUM SPEEDS
As the Blower Switch is moved through positions "M1" and "M2", the switch bypasses part of the Blower Motor Resistor, allowing more voltage to be applied to the Blower Motor, which will increase its speed.

HIGH SPEED
When the Blower Motor Switch is in "HI," voltage is applied to the coil of the Blower Motor High Speed Relay. The Blower Motor High Speed Relay is energized removing the Blower Motor Resistor from the circuit. Battery voltage is then applied directly to the Blower Motor though the Blower Motor High Speed Relay contacts. The motor runs at maximum speed.