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.
AC vacuum-controlled door actuator main fault
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.
Do you need assistance with the ac vacuum-controlled door in your vehicle?
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!
There is a vital relationship between the ambient temperature and the ac air temperature coming out of the vents. The hotter the outside ambient temperature the harder it will be for the vehicle air conditioning system to cool down the inside of the vehicle. In hot and humid weather we need the vehicle cooling system operating at 100 % efficiency as well as a clean condenser with no missing or bent fins.
Auto ac condenser. Subcooling and superheat process.
In range normal auto ac vent temperature according to manufacturer specifications will greatly depend on the subcooling and superheat processes. The refrigerant in a vapor state coming from the ac compressor needs to be de-superheated, condensed from vapor to liquid and subcooled before leaving the air conditioning condenser to the metering device (TXV or FOT).The more the radiator fan assembly is able to cool down the ac condenser improving the condenser subcooling process the better liquid refrigerant will go through the expansion metering device minimizing the flash gas and inefficiencies.
Auto A/C superheat. Evaporator core and air vent temperature.
Well subcooled liquid refrigerant going through the thermal expansion valve or fixed orifice tube and expanding in the evaporator core will be in charge of carrying the heat out of the vehicle cabin. The heat inside the vehicle will be carried out of the vehicle by the refrigerant superheated in the evaporator core and changing state from liquid back to vapor. To reach normal auto a/c vent temperature we need the evaporator core free from debris and a well maintained ac cabin air filter (If the vehicle has one installed).
Auto A/C compressor and proper refrigerant charge.
The auto a/c refrigerant is the vehicle to move the heat from inside the vehicle to another place outside of the vehicle. This movement or refrigerant flow will depend on good automotive a/c compressor to take care of that and the specific amount of refrigerant and oil circulating in the system according to manufacturer specifications.
Do you need assistance checking the Normal auto A/C vent temperature in your vehicle ?
The car ac should be as cold as the manufacturer design specifications according to the heat load, humidity, and other conditions of the vehicle at the time of the performance test. There is a relationship between Humidity, ambient air temperature, pressures and the type of refrigerant used in the auto a/c system that will ultimately dictate what the center duct air temperature in your car should be. In this chart of Relative humidity/ambient air temperature/pressure for r134a we can determine what should be the car ac temperature at the vents. If the vehicle is under these specific conditions of ambient outside air temperature and humidity and the Center Duct air temperature is not close to these values, there is a problem with the car a/c system that must be fixed.
Ambient Air Temp (F)
Max Gauge Pres Low Side (psi)
Max Gauge Pres High Side (psi)
Center Duct Air Temp (F)
Temperature /Humidity/Pressure Relationships for R134a.
Do you need assistance checking your auto ac system up ?