Automatic Temperature Control: Components: COMPENSATOR
The compensator regulates the amount of vacuum applied to the vacuum motor by venting the engine vacuum supply. In-car air from the grille at the top of the instrument panel is drawn into the in-car air inlet port on the compensator. Ambient air is supplied to the compensator at the air inlet port from the blower. This ambient air is then split and a portion of it is blown through the bottom of the horizontal tube in the compensator to create aspiration which causes the in-car air to be drawn into the compensator.
The other portion of the ambient air is forced through the aluminum compensator tube located in the upper horizontal tube of the compensator.
The in-car air that is drawn into the compensator passes over the outer surface of the aluminum compensator tube which has been warmed or cooled by the ambient air passing through it. This tempered in-car air then passes through the bimetal sensor coil. The sensor coil applies a force against a rubber diaphragm which seats against a vacuum port which regulates the supply of vacuum to the vacuum motor.
When the control panel temperature lever is moved, the temperature control cable moves a lever attached to the sensor coil. When the lever attached to the sensor coil is moved, sensor coil tension is changed to provide control of comfort level at the selected temperature lever position.