Air Conditioner

Easy to understand guide on how automotive air conditioner systems work, this information pertains to most vehicles.

An air conditioner or climate control panel is designed to operate the various settings to improve occupant comfort, these controls may differ in appearance but perform the same basic tasks.

Climate Control Panel
When a command is given to prompt the air conditioner system to activate, an electrical signal is sent to the engagement clutch coil or internal valve of the compressor.

Refrigerant (134a) is then circulated throughout the system as it is compressed. Once compressed, the 134a travels to the condenser where it is cooled and transformed into a liquid state.

The low pressure port is connected to the low side of the evaporator, a serpentine belt is used to utilize engine power to rotate the internal workings of the compressor. High pressure ports are always smaller is size than low pressure ports. To replace the compressor visit - Air Conditioner Replacement

Air Conditioner Compressor
Once the compressed (heated gas state) refrigerant has left the compressor it is transferred to the condenser via a high side hose were it is cooled and condensed back into liquid form.

Some condensers are designed with a receiver dryer attached which acts as a refrigerant cleaner/moisture remover. To recharge your air conditioner visit - How to Recharge Your Air Conditioner

Air Conditioner Condenser (Removed)
After the compressed refrigerant is cooled by the condenser it enters a high side hose in liquid form which is attached to the expansion valve or orifice tube which releases the refrigerant as low pressure into the evaporator.

This release causes the liquid to turn into a gas inside of the evaporator core, this expansion creates the absence of heat (coldness). The evaporator core is located inside the passenger compartment or just outside the firewall. After completing its journey through the evaporator, the refrigerant is returned to the compressor via the low side hose where the cycle begins again. If your air conditioner is not working visit - Air Conditioner Troubleshooting

Evaporator Core (Heater Plenum Removed)
The climate control blower motor is used to push air through the evaporator core which delivers the cold air flow into the venting system and onto the occupants of the vehicle.

Blower Motor
This diagram shows the system and refrigerant flow, these systems are closed (sealed) which continuously re-circulates the refrigerant. After the system has been repaired it must be vacuumed down and recharged visit - Vacuum Down and Recharge Your Air Conditioner

Air Conditioner System
Helpful Information

Hoses and components should be checked for deterioration, bubbles, cracks, hardening or oily residue which could be signs of leakage. Visit - Air conditioner condenser replacement

Leaking Condenser
Proper refrigerant levels should always be maintained, low system refrigerant charge is a common cause of a weak AC system. Odors can developed in the air conditioning system when a fungus has grown on the evaporator core, aerosol disinfectants can be used to remedy this condition. Refrigerant charging kits are available at many auto parts stores. Leaves and dust particles can get logged in the condenser hindering its performance, use a garden hose or compressed air to clean the condenser in front of the radiator regularly.

(Note: An air conditioning system is under high pressure, until the system is discharged completely, no repairs should be performed. Eye protection should always be worn when working with an air conditioner.)

If further assistance is needed, our certified car repair technicians are ready to answer car repair questions for free.

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