If you have acquired or purchased a smaller air compressor for your home or garage workshop, chances are it did not come equipped with a compressed air filter. Do you need a compressed air filter, then? If so, why?
In the market place drive to offer the consumer the cheapest possible off-shore manufactured air compressor, not including a compressed air filter saved the compressor company a few dollars per air compressor, and allows them to keep their wholesale prices, and ultimately the consumer sell price a little lower.
In so doing, for most users of air compressors, they have not done you any favors.
Water is generated right away
As soon as any air compressor starts pumping air into the tank, it is also pumping free water and water vapor into the tank too.
How much water ends up in your air compressor tank?
That is determined by a number of factors; how long the compressor is running at one time, how hot the compressor gets, the volume of compressed air being used, the ambient temperature and humidity of the air flowing into the air compressors intake port… many factors, few of which you have any control over.
Essentially, there could be lots of water pumped into the compressor tank along with the compressed air.
How do you use the compressed air?
What have you got hanging on the end of your air hose from the compressor? An air tool? A spray paint gun? Just a blow gun?
Regardless, whatever you are blowing compressed air into from the compressor will likely be negatively affected by the water coming from the compressor tank along with the air.
Do your equipment a favor and add a compressed air filter.
What size of compressed air filter?
A rule of thumb is that the intake port on the compressed air filter should be the same size as the air line that is feeding it. That will work for most small air compressors, as the capacity of even a mini-air filter easily outstrips the amount of air that a small air compressor can deliver.
If your air compressor is more than a couple of HP in motor size, rather than use a mini-filter similar to the one shown in the photo above, consider purchasing a regular sized air filter that has the flow capacity of your compressor.
What’s flow capacity? Well, typically an air compressor can pump out about 3-4 CFM of compressed air at 90 PSI for each HP of motor size. The compressed air regulator will have a flow capacity shown on the box or the documentation that comes with the filter.
Just make sure that the capacity of the filter exceeds the flow capacity of the compressor and you are fine.
And yes, periodically you want to replace the filter element in the compressor filter as it clogs up with crud brought down from the compressor by the flowing compressed air.
Got a question about compressed air filters? Ask it below.