Symptom:
Vent Airflow Does Not Change
Condition
Airflow from the HVAC vents does not increase or decrease after changing the blower fan speed switch position.
Detection
The condition is most easily observed by placing a hand near one of the HVAC vents while changing the blower fan speed to feel for any changes in air movement.
Description
Airflow is produced by a blower motor located in the HVAC box. The motor is equipped with a two-wire connector for power and ground circuits. Both of these elements must be present for the motor to turn on. Depending on the system design, one of the two elements is removed to turn off the motor. Similarly, motor speed is controlled by placing a resistor or transistor into one of these two circuits.
Recommended Tests
No results found.
Similar Symptoms
Need More Help?
Don’t give up! Start a conversation in our Community Support forum!
