The accumulator, also known as a receiver-drier, is an essential component found in some air conditioning (AC) units, particularly in automotive AC systems and certain heat pump systems. Its primary purpose is to ensure the efficient and reliable operation of the AC system by performing two critical functions:
Moisture and Contaminant Removal: The accumulator acts as a moisture and contaminant trap in the AC system. When the refrigerant circulates through the system, it can sometimes carry small amounts of moisture and contaminants like dirt, debris, and oil. These impurities can be detrimental to the proper functioning of the AC system. The accumulator contains a desiccant material, which absorbs and traps moisture, as well as filters to catch contaminants, preventing them from circulating further in the system.
Refrigerant Storage and Regulation: In certain AC systems, especially those equipped with a fixed orifice tube as a metering device, the accumulator helps regulate the flow of refrigerant. The accumulator acts as a storage reservoir for excess refrigerant that may not be needed at the evaporator coil. It ensures that only vaporized refrigerant reaches the compressor, preventing any liquid refrigerant from entering the compressor, which can cause damage or compressor failure. This is particularly crucial during low-load or low-temperature conditions when the system operates at lower capacity.
During normal operation, the accumulator is installed on the low-pressure side of the AC system, usually between the evaporator coil and the compressor. It is typically a cylindrical or can-shaped container, and you may find it hanging with the compressor or somewhere in the vicinity of the evaporator coil.
It's important to note that not all AC systems require an accumulator. Some modern AC systems utilize alternative designs or components to achieve similar functions. The presence of an accumulator depends on the specific design and requirements of the AC system in question.