Expansion Valves for Car A/C Systems | Valeo Service

The expansion valve is a component of the automotive air conditioning loop and helps to control the system.

The expansion valve for car A/C has a few different roles:

• It controls the drop in pressure in the A/C system needed to evaporate the refrigerant and generate cold
• It controls the flow rate of the fluid in the evaporator
• It controls the evaporator output temperature (superheating)

The expansion valve is located downstream of the receiver drier in the A/C loop. The expansion valve receives the refrigerant fluid in an already-filtered, 100% liquid state. It then reduces the refrigerant fluid pressure before it enters the evaporator. This pressure drop cools the fluid, which is then sprayed into the evaporator. The expansion valve for car A/C is always attached to the evaporator.

The expansion valve is a precision component, it is complex and sensitive to any residues and acids circulating in the air conditioning loop. A blocked expansion valve may cause either a notable lack of cold or the destruction of the compressor (a failure of flow regulation leads to fluid entering the compressor in a liquid state).

Valeo OE Expertise

Valeo is a world reference in components for automotive air conditioning and has been a pioneer in manufacturing parts for car A/C systems since 1950. As a manufacturer of original equipment for automakers, Valeo produces high-precision expansion valves, ensuring efficient and safe operation of the entire A/C loop.

Valeo Info

• Regularly checking the proper functioning of the receiver drier and changing it when necessary are essential to guaranteeing its longevity. 
• If you detect any iron filings when replacing the compressor, replace the expansion valve.