Programmer

DESCRIPTION

The programmer converts electrical signals from the heater and A/C control assembly into vacuum commands which position the mode, A/C-defrost, and outside air valves in the air distributor assembly.

OPERATION

Vacuum is constantly applied to the programmer check valve which distributes the vacuum to four solenoid-controlled valves in the programmer. When the heater and A/C control signals the programmer to change an air distributor valve position, the associated solenoid energizes and vacuum is applied to the proper actuator.

The programmer also utilizes a bi-directional DC motor. This motor operates on signals from the heater and A/C control assembly that result from inputs from the in-vehicle and outside air temperature sensors and the set temperature. As the motor turns, it moves a link rod connected to the temperature valve in the heater and A/C module to obtain the correct blend of heated air from the heater and cooled air from the A/C evaporator. The motor is the only replaceable component in the programmer.