Thermal switches are used on both the low and high side of AC systems. A Thermal switch may be connected in series with the compressor clutch.
A thermostatic switch de-energizes the clutch and stops the compressor to keep the evaporator from freezing up. When the temperature of the evaporator approaches the freezing point (or the low setting of the switch), the thermostatic switch opens the circuit and disengages the compressor clutch. The compressor remains inoperative until the evaporator temperature rises to the preset temperature, at which time the switch closes and compressor operation resumes.
A thermal limit switch may be mounted on or near the compressor and is used to stop compressor operation before the temperature of the compressor reaches a point of damage.
The air delivery system controls the movement of heated and cooled air into and throughout the passenger compartment. The Hvac housing is the plenum unit located and beneath the instrument panel. It contains the evaporator, heater core, the blower motor assembly, blower speed control device and the vacuum controlled door actuators.
The plenum houses the air doors and door actuators that direct airflow to the correct ductwork. The doors may be controlled by cables, vacuum, or electrical actuators. Single zone systems are usually equipped with three doors.
Automotive ac climate control panel levers may operate a rotary switch to select the various vacuum or air routings to the motors that control A/C modes. The main fault experienced with vacuum-controlled door actuators is vacuum leaks.
We have auto ac mechanics in your area in Miami-Dade County. Some ac door actuators may be located underneath the dashboard of the vehicle and to get access to them could be labor intensive. Give Us a Call Today!