The Receiver Drier
Receiver driers are used on (TXV) thermal expansion valve systems. They are similar in operation to the accumulator used on fixed orifice tube systems because they both remove moisture from the system. There are some key differences though; the receiver drier is located on the high side of the system, between the condenser and the evaporator. The accumulator is located on the low side, between the evaporator and the compressor on fixed orifice tube systems.
The receiver drier is a liquid storage tank for the refrigerant flowing from the condenser. This insures that the necessary liquid refrigerant is consistently supplied to the expansion valve under all operating conditions. At the most demanding times of the day, the opening expansion valve relies on this storage tank to provide the evaporator core its full supply of liquid refrigerant.
Refrigerant from the condenser enters the receiver drier through the inlet port. The vapor rises to the top, while the heavier liquid refrigerant drops to the bottom. It passes through the filter and desiccant and is then stored in the bottom of the tank. As the expansion valve opens and closes, the liquid refrigerant is drawn into the outlet port tube of the receiver drier, through the high pressure line, and onto the expansion valve.