The mineral oil contained in the working agent has hygroscopic properties, i.e. it absorbs moisture. The air dryer protects the AC system against excess moisture. Special filtering layers retain any metal filings, sediment, dirt and water, which may damage the compressor and the expansion valve. The AC system should be inspected on a regular basis.
What is the AC dryer filter?
The car air-conditioning system is equipped with a dryer. The dryer removes moisture from the AC system that could damage the AC compressor and the expansion valve. The mineral oil contained in the working agent has hygroscopic properties, i.e. it absorbs moisture. The dryer filter should be replaced if the AC system's performance is compromised.
How is the dryer filter replaced?
The dryer filter housing has a sight glass through which you can inspect its wear level. If clogged completely, the filter prevents AC from operating properly and may even cause a failure of the compressor and other system components. It should be changed every 2 or 3 years in order to ensure that it is in a good condition and protects the AC system in your car. Changing the filter requires removing the working agent from the AC system, unscrewing the filter together with its housing, and fitting a new filter in its place. Next, the system is checked for leaks and refilled with the working agent, frequently the one previously removed.
What else to keep in mind?
The filter should be changed in a specialized garage equipped with appropriate AC handling tools. Changing the filter is also a perfect opportunity to check the level of the working agent and the compressor oil, as well to apply a cleaning treatment to air ducts, and to fit a new cabin filter. This way you can be sure that your AC works properly and will continue to do so whenever you need it.