Also known as driers, receivers are critical in Porsche A/C systems that have expansion valves. They typically look like metal cans containing an inlet and an outlet and are commonly located on the system's high-pressure section. It is basically located just between the condenser outlet and the expansion valve inlet. There are some models where the receivers are connected directly to condensers.
What are their Functions?
Driers are called receivers basically because they function to receive and store refrigerant when there is low cooling demand in the system. It filters any debris or dirt that has been trapped in the air conditioning system. It contains a desiccant which is responsible for absorbing moisture that may get in the A/C system. It assures that the system is dry at all times during manufacture, assembly, or service.
What if the Receiver Malfunctions?
With such an integral role to play, your concern will be what will happen in case it malfunctions. It follows that it will not be able to absorb excess moisture. This will then allow that same moisture to easily spread to the A/C system and its components. This will then result in damages. Since corrosive acids are formed as moisture mixes with the refrigerants, pipes and hoses will corrode thus resulting to leaks.
Does this Mean You Need to Replace it?
Receivers have to be replaced once the A/C system has been opened for service because this is what most compressor warranties recommend. Remember that there is a desiccant in the drier which is responsible for trapping moisture and when the system has been opened for service, the entire unit will be exposed to moisture as well. This will compromise the function of the desiccant because it becomes saturated thus rendering it ineffective. The receiver's filter will also accumulate dirt and grime which will prevent it from protecting the A/C in the future. The oil and refrigerant flow will also be compromised in the process.
What are the Signs that the Receiver is Malfunctioning?
The receiver is already malfunctioning once you notice problems arising in many parts of the air conditioning system. These problems will require that you make the necessary inspection. You can take notice that there are noises that seem to be rattling from the engine. Since receivers are enclosed in a chamber, a malfunctioning receiver will often mean that the chambers have been contaminated with and the rattling noise is an indication of that. Loose fittings may also lead to that noise. It is best to inspect the receiver and have the problem addressed as soon as possible.
A malfunctioning receiver can also come with a moldy smell. This bad smell is an indication that moisture has not been removed by the receiver from the system. The foul smell results from mold and bacteria caused by moisture which is an obvious sign that the receiver no longer does its task of absorbing moisture.
You should never take any of these signs for granted. Once you have established that something is wrong with the receiver, you must have the worn out part replaced right away. Make sure you get the part suited for your Porsche car model.