While often overlooked in comparison to the compressor, the accumulator also plays a critical role in maintaining the A/C system's health, serving as an equalizer and reservoir for the refrigerant and oil necessary to protect the compressor. In fact, just think of it as the compressor's personal bodyguard.
Same as the accumulator dehydrator, the receiver drier is the compressor's watchguard, making sure it has enough refrigerant and oil circulating throughout the system for optimal performance. The only difference from the AD? Where it is located in the A/C system flow and the vehicle application.
The Delphi Difference
Lightweight in size, this heavyweight of compressor protection features aluminum construction
Calibrated oil return in the outlet tube for effective separation of liquid and vapor
A molecular sieve desiccant effectively controls moisture and helps protect the entire system against corrosion
You can trust you will get an exact fit every time due to its OE quality standards
Receiver driers are there to absorb corrosion-causing moisture and to filter any particulates that are circulating around the system, such as:
If moisture has been present in a system for a period of time, rust could form on any metal parts. This rust can flake and be transported around the system by the refrigerant.
If the compressor seizes and fails, it could start to break up internally and these bits could find their way around the system.
Silica gel granules
Once totally saturated, the drying agent in the drier turns to mush and circulates around the system.
Grease and general debris
If a system has been opened for a repair and the drier has not been replaced, general workshop debris could enter the system.
Designed and manufactured to OE specifications, Delphi offers an extensive range of receiver driers. Its OE-designed internal components provide improved separation of liquid and vapor, while a molecular sieve desiccant effectively controls moisture and helps protect the entire system against corrosion. They also feature lightweight aluminum construction and a calibrated oil return in the outlet tube for enhanced lubrication.
Delphi Service Centre garages are trained in the very latest air conditioning technology. They have access to a wide range of OE quality parts, as well as the tools and knowledge to service these systems.
The receiver drier is located after the condenser on the “high pressure” side of the system. It has a filter and desiccant sealed in a container. Its job is to temporarily store refrigerant that has been liquefied by the condenser and to remove dirt and moisture that could cause damage to the refrigeration system.
Sometimes there is a glass window on the top of the receiver drier which allows technicians to check the condition of the refrigerant, but this has been phased out now on most vehicles. It is referred to as a “sight glass.”
The big fact about receiver driers is that they are a serviceable item. They are a filter and should be viewed as such. All the other filters on a vehicle such as the oil filter, air filter and fuel filter are regularly replaced – if not, then the vehicle will not operate correctly. The same is the case with the receiver drier. If it is not replaced, it will become clogged and potentially release the debris around the system, causing blockages and damage. It is cheaper in the long run to replace the receiver drier regularly than flush the blockages out of the system and/or replace major failed components such as the compressor.
Sometimes on small vehicles, the receiver drier is fitted into a tube on the end of the condenser, making it difficult to spot.
A receiver drier is fitted with a thermal expansion valve. If you cannot find either, it means that the system is fitted with an orifice tube and a
Essentially the job of the accumulator is very similar to that of the receiver drier. It collects water, dust, dirt and debris from the system and stores them in desiccant. It is also a serviceable item – just like the receiver drier.
The difference is that the accumulator is fitted after the evaporator. This means it filters a gas, not a liquid refrigerant, and it is on the low pressure side of the system, not the high.
The accumulator therefore is very important. It is the last component before the compressor. Accumulators are noticeably larger than receiver driers. This is because they have a large volume to reduce the pressure of the gas even further – ensuring that there will be no liquid entering the compressor. As mentioned before, low pressure means low temperature. It is often therefore referred to as a reservoir.
Accumulator Dehydrator (A/D)
Separates liquid and vapor refrigerant.
It stores liquid refrigerant and lubricant.
Contains drying agent (desiccant).
Removes moisture from refrigerant as it passes over the drying agent.
Has lubricant bleed hole to provide a lubricant return path to compressor.
Replace the accumulator dehydrator (A/D) or receiver drier (R/D) when replacing the compressor, when the system has been open for an extended period of time or when sealant or other system debris is present. On condensers with an integral R/D where the desiccant is removable, replace the desiccant only, not the condenser. If the desiccant cannot be replaced, condenser replacement is required.
Our Tech Tips for Accumulator Dehydrators
Do keep shipping caps on the A/D or R/D at all times except when adding oil to the part, or when ready to install to refrigerant lines.
Reason: Open units will absorb humidity from the air, reducing or eliminating the internal desiccant’s ability to capture system moisture.
Do finger start the attaching line set nuts.
Reason: This will help ensure that the fitting threads do not become cross threaded.
Do not spin the A/D or R/D on the mating line set in an attempt to assemble the joint.
Reason: Spinning the A/