Receiver Dryer: Description and Operation

Suction Accumulator/Drier

The suction accumulator/drier is mounted on the front of the A/C evaporator core and attaches directly to the outlet tube. A suction service access gauge port valve is mounted on top of the suction accumulator/drier. Its purpose is to provide service access to the suction side of the refrigeration system for pressure reading and system diagnosis.

As refrigerant enters the suction accumulator/drier when charging or during air conditioning system operation, the liquid portion of the refrigerant and the system lubricating oil fall to the bottom of the accumulator can. A small diameter oil bleed hole, approximately 8mm (3/10 inch) above the bottom of the can in the J-shaped outlet tube, allows the accumulated heavier liquid refrigerant and oil mixture to re-enter the evaporator to compressor suction line at a controlled rate. As the heavier liquid refrigeration and oil mixture passes through the A/C compressor without causing A/C compressor damage due to liquid slugging. The gaseous portion of the refrigerant is drawn out of the accumulator can tat the upper end of the J-shaped tube by compressor suction.

A fine mesh screened filter fits tightly around the oil bleed tube to prevent contaminants from plugging the oil bleed hole.

A desiccant bag is mounted inside the suction accumulator/drier to absorb moisture which may be in the refrigerant system.









A fitting on the top of the suction accumulator/drier is used to mount the A/C cycling switch. It has a long travel Schrader-type valve stem core installed in the fitting opening to prevent refrigerant loss when the A/C cycling switch is removed. Use only the correct service replacement part which has a standard short travel valve. That will prevent the A/C cycling switch from seating when installed, causing refrigerant to leak from the system or causing damage to the A/C cycling switch.