Plumbing
      Compressed Air ..2



The first page of information on compressed air plumbing is found here, and talks about the plumbing of a home workshop type portable compressor. Plumbing compressed air is continued on this page.

This page discussed the fixed compressor installation.

While hard-piping of an industrial air compressor is normal, some folks opt to have a portable compressor able to be connected to fixed plumbing in the shop, and then use the portable plumbing when they have moved the compressor elsewhere.

The concepts for both heavy duty industrial compressor and home shop compressor plumbing are essentially the same. It is the cost that will vary substantially as industrial compressed air plumbing is more complex, parts are larger, and as a result are far more expensive.

What Pipe When Plumbing Compressor


It occurred to me that, so far, I have not talked about what air pipe to use when plumbing compressed air runs.

If you want to read about it now here is in-depth information on compressed air piping materials.

Fixed Compressor Installation


Filter First: First off, you will want a general purpose filter installed at the discharge of the compressor. That filter port size must be either the same pipe size as the discharge line, or bigger. If the filter is installed right at the outlet for a large compressor air tank, for example, using a filter with a smaller port size may result in inadvertent restriction of the air flow from the compressor tank to your plant air mains.

What compressed air filters do and how they operate can be found here. There is not much point in rewriting all the info and adding it to this page. Go to the filters section first, if you are not sure about them, please.

Air Regulators Next: While small portable air compressors come with a regulator installed on the compressor discharge as a norm, there is generally no need to install one on the discharge from a larger, fixed installation compressor discharge unless the air is going to just one station. Then using the regulator on the discharge from the compressor tank to reduce the output pressure to the sole air use station makes sense.

I am a strong proponent of throttling down air pressure at the point of use to the minimum air pressure necessary for the air tool. This will reduce compressed air use and wear and tear on both the air compressor and air tool.

Install an air regulator at every point-of-use in the shop. Adjust the pressure to the optimal setting for that piece of equipment. This will help reduce air waste and save money.

Here is in-depth information on air regulators.

After Cooler: In the drawing I show the compressed air passing through a compressed air cooler, one of which you will need if your plant is consuming a lot of compressed air.

High consumption of air means higher air temperature entering the plant mains. That typically means more water will end up in the air mains. Here is why!

The drawing also shows a drop leg and drop leg drain (very important) as the air line from the compressor tank heads up to the ceiling mains in the plant or shop.

Plumbing Compressed Air

If you are plumbing compressed air from the compressor for plant use, plumb the air in a similar fashion to what is shown in the sketch above.

If it is a home shop you are plumbing air for and you want a hard-plumbed-station into which you can plug the air from your portable air compressor, then this is the right way to plumb that station, particularly if you are going to be using the compressor in the fixed-installation a lot.

You have now plumbed properly from the compressor discharge or from the air tank, through to the air filter, perhaps through cooler or drier, and then to a Tee.

Below the Tee there is a section of drop line, at the end of which is a drain. This could be a manual drain, or an automatic float drain. If you use an lot of air, make this an auto drain, so maintenance does not have to worry about remembering to drain it regularly.

Now you want to make the connection from the riser air pipe into the ceiling air mains.

Compressor Plumbing At The Ceiling:


Plumbing Compressed Air

The line that goes up to the ceiling, whether supplying air up to the main, or bringing air from the main back down to an application, loops over the pipe and connects where shown in the photo.

Any water that is in the air line already will tend to stay in the riser, dripping down to the auto drain at the bottom. Any water that condenses in the air main, will tend to stay in the main, rather than following the air drops down to the air using equipment. Installed this way the water can flow along the air mains to a drop leg with an auto drain.

Do you plumb this way for your home workshop? Entirely up to yourself and the amount of air you expect to be using and the expense involved. If your air use is measured in hours rather than minutes, it is probably a good idea to install your air supply lines properly.

Here is more on plumbing compressed air.