Refrigerant Dryers for Compressed Air

A refrigerant air dryer is is used with compressed air for removing moisture from the compressed air system . Compressed air always contains water because your are taking in outside air which contains moisture. It is vital to have a compressed air dryer system in place to protect your equipment and tooling from damage. How does a refrigerant dryer work and why select this type of dryer system?

Refrigerant air dryers are commonly used as they are easy to operate, economical and low maintenance. Once installed it is likely that you may never have to think about it again. The system works by cooling the air to around 37 degrees Fahrenheit. At this point all the water vapor condenses into water. The water can then be removed by a simple water trap. Once the liquid water has been removed the air gets reheated to room temperature. Since most of the water has been condensed and removed the reheated air will be significantly dryer than from before.

Fundamental Schematic of a Refrigerant-Type Dryer

The cooling process of refrigerated dryers is the same process used in refrigerators and freezers. The liquid refrigerant is evaporated in a separate circuit and used to cool down the compressed air. As the air cools the refrigerant gets warmer. The refrigerant moves into a compressor and gets re-cooled in a condenser, this process is a continuous cycle as more air is introduced into the compressor.

Here a few items to consider when making your purchase:

Maximum pressure: The dryers max pressure should be the same or higher than your compressor.

Inlet Temperature: If you exceed maximum inlet temperature you are at risk of damaging parts of your equipment. Some refrigerated dryers have an after cooler making sure your compressed air stays within acceptable temperature ranges.

Maximum Flow: Make sure your dryer has the capacity needed to there are no drops in air pressure.

Maximum Room Temperature: If you are placing your refrigerated dryer into a room with a hot environment there is a change that it could overheat, Make sure that your max operating temperature for the dryer is able to accommodate the max temperatures in the room where it will be operating.

EXAIR wants you to be successful in every aspect of your compressed air system. If you have a need for any of EXAIRS Intelligent Compressed Air Systems please give any of our Application Engineers a call or contact us through our TecHelp.

Eric Kuhnash
Application Engineer
E-mail: EricKuhnash@exair.com
Twitter: Twitter: @EXAIR_EK