Compressor Air Filter

Choosing the Right Filter

Filters are essential part of any air compressor. Choosing the right filter will ensure that your system will have fewer problems. This will save you hours of down time and the cost of replacement parts over the lifetime of your system.

Air compressor filters consist of the following parts.

Air goes through the inlet. There is a cap plumbed internally that forces the air to go downwards and whirls into the filter bowl. This action resembles the movement of a cyclone, and it will force water and trash that is sometimes in the air against the sides of the bowl and eventually down to the bottom.

2. The filter cap may be made of plastic or metal. This depends on the maker.

Proper air filter functioning is dependent on the air running through the piece in the right direction from the supply line that stems from the filter discharge. By looking at the cap of the filter, you will be able to tell the right direction of air flow. There is most often an arrow on the cap that points in the proper direction. If you happen to reverse the air flow, your air filter won’t work right.

3. There is a dotted line that reveals the course of the air that has been compressed as it moves to the filter discharge. If the compressed air is to leave the filter through this course, it must have been through the phase of cyclonic action, and then gone through the filter element, which makes the airstream more pure.

4. The filter discharge lets the stream of compressed air go through the filter and pass through the airline to your product. Fitting sizes for the discharge port and the inlet port are usually the same. Many manufacturers of filters make adapters that let you alter the fitting size of the port. It is possible to use a bigger filter unit on a small air line, doing the opposite can interfere with air flow. If you use an air filter that is undersized, expect a choke point.

5. The filter element can become clogged and cut off the supply of air. You can try cleaning or replacing it, but this depends on what type it is.

Many manufactures include a Delta P gauge in their assembly. This lets you know if the pressure decreases across the filter. An increase in the pressure drop means that the element is working fine.

Filter elements for general use are 30 or 40 micron sized. Some uses will require a 5 micron element, but if your air quality is poor, the element may rapidly. You want to use a general purpose filter with a five Micron element. When you move on to the nicer components like coalescing filter types, first use the general purpose, a Micron 5, and at the end, a coalescing filter.