Receivers or driers are usually used in car A/C systems that use expansion valves. They are not so hard to identify as they resemble metal cans fitted with inlets and outlets in the high pressure section of the A/C. In Volvo models, they are located between the condenser outlet and the valve inlet. Some models may have theirs connected directly to the condenser, so examine your car to know exactly where the receiver is. So what exactly do they do and why are they important? Can your car A/C system run without a receiver? Read on to learn more.
Receivers are in very simple words, temporary storage units for oil and refrigerants. In fact, the term receiver is derived from this vital function mainly because they receive and store oil and refrigerants during random periods of low cooling demand. To make them work better, they are fitted with filters that trap debris inside the A/C system.
Receivers also contain desiccants which absorb moisture in the A/C system. This is an important function for a very simple reason. During assembly, moisture can easily get into other air conditioner components. The drier comes in to ensure that the entire system remains dry not just during assembly but at all times.
How Important Are Driers?
Excess moisture in your car A/C system cannot be absorbed any time the drier malfunctions. This means moisture will spread to other A/C components and cause more damage. Remember that when moisture comes in contact with the accumulator, the refrigerant will mix with air in the moisture. This will form corrosive acids within minutes. Before you know it, pipes and hoses leading to the refrigerant and oil will corrode and causes leakage.
Your compressor warranty most likely requires you to replace the drier anytime the A/C system is opened for service. Note that the desiccant inside the drier is deigned to absorb just a certain amount of moisture. So when the system is being serviced, it becomes exposed to moisture since it is completely opened. At this point, the desiccant becomes saturated and ceases to function. It simply becomes ineffective. Note too that the filter inside the drier will have accumulated some debris by the time you take the A/C system for servicing. This can damage the entire system by diminishing refrigerant and oil flow. With that in mind, take your car A/C system for servicing as often as you can. Only then can the drier be replaced on time.
Signs Of A Failing Drier
Your drier will not take you by surprise and fail when you least expect. It will first give you signs of failure. Take note of rattling noises. The noise comes about because driers are enclosed in a tight chamber. Rattling noise therefore means that the chamber is contaminated. It may also be a sign of a serious internal damage. Loose fittings can also cause the rattling noise. Have the problem assessed quickly to prevent further damage. The assessment and examination must be done a car A/C system expert.