Auto A/C Terms - Glossary
Evaporator Equalized Valves in Receiver - EEVIR- VIR

A design change made on General Motors A/C systems in the early 1970s incorporated the expansion valve, suction valve and receiver drier into one unit known as a VIR assembly or Valves in Receiver. A slight design change to that was the EEVIR unit or Evaporator Equalized Valves in Receiver assembly.

As for appearance, the EEVIR looked identical to the VIR assembly. It also performed all the same functions, incorporating the receiver drier into the assembly. In fact, the VIR assembly was the only receiver drier on automotive systems that allowed the desiccant alone to be changed. It was a cost effective design.

Mounted at the outlet of the evaporator, the EEVIR modification was nothing more than the addition of an internal port between the chamber that held the suction valve and the one that held the expansion valve. The addition of that equalizer port allowed for a faster and more accurate reaction of the expansion valve.

With the addition of the equalizing port, the expansion valve could better regulate the flow of liquid refrigerant into the bottom of the evaporator and provide overall better cooling performance. When servicing these assemblies, it was important to understand that the entire assembly was interchangeable with the VIR assembly, but components of the EEVIR were specific to that assembly.