Manual A/C-heater system consists of heater core, blower motor, compressor, compressor clutch, condenser, evaporator, A/C cycling switch, A/C compressor relief valve, A/C clutch relay, A/C pressure transducer, vacuum controlled airflow control doors, pollen filter and ducting to distribute temperature controlled air. A/C system is a cycling clutch type with a fixed orifice tube. Manual A/C-heater system heats or cools vehicle interior depending on function selector position and temperature selected. See Fig. 1 .
BLOWER MOTOR RESISTOR
Blower motor resistor is located behind glove box, on evaporator housing. Blower speed is determined by current path through 3 resistor elements. During high speed blower operation, resistor elements are by-passed. A thermal limiter in blower motor resistor protects blower motor circuit. If resistor overheats due to excessive heat, thermal limiter opens, preventing current flow through resistor elements. Thermo limiter will open at approximately 250 F (121 C).