The duct and valve assembly which regulates the air flow from the cool and heated air sources is attached to the air cleaner. The flow is regulated by means of a door that is operated by a vacuum motor. The operation of the motor is controlled by the bimetal sensor.
- If the duct door is in the "closed to fresh air" position, remove the hose from the air cleaner vacuum motor.
- The door should go to the "open to fresh air" position. If it sticks or binds, service or replace, as required.
- If the door is in the "open to fresh air" position, check the door by applying 8 in. Hg or greater of vacuum to the vacuum motor.
- The door should move freely to the "closed to fresh air" position. If it binds or sticks, service or replace, as required.
Make sure the vacuum motor is functional before changing the duct and valve assembly.
REMOVAL & INSTALLATION
- Disconnect the vacuum hose from the vacuum motor.
- Separate the vacuum motor from the vacuum operated door and remove the vacuum motor.
- Installation is the reverse of the removal procedure.