Plumbed for Air

Here, I've plumbed the aircraft factory (garage) for compressed air. It's both a convenience to have air outlets in more places and important to condition the air. Air compressors heat the air when compressing it. That causes problems because when the air cools, it condenses moisture which ends up inside tools or paint guns.

My solution to the moisture problem was to pipe the air through steel pipe which allows the air to cool and then give it a place to go before getting to the tools. I've got risers like the one pictured here that send the air up and the water down to a drain. Not real interesting but important for keeping rust out of your tools or spots out of your paint.

I promised my friend John that I'd help him with his layout for his garage so I annotated the pictures below and added an abbreviated description of what I did.

1. I used 3/4" galvanized steel piping for the perimeter and 1/2" for each drop leg. I tried to slope the pipe toward every drop to help control moisture. Water goes down, air goes up. On some of the drops, I just used a 3/4" Tee.

2. I used several unions in the perimeter piping. Unions allow you to disconnect the two pipes on either side of the union without turning either pipe to unscrew it. I was able to build the system in sections and put them up one section at a time. It really made it easier to trouble shoot leaks since I could just remove one section and work on it while leaving the rest in place.

3. The basic set-up of each drop is shown above. I used 1/2" unions on each branch-off from the drop to allow me to remove it without having to twist pipe. I used brass ball valves on the bottom of each drop as that's where the water will collect. On some of the drops, I added a male air fitting after the ball valve which allows me to add another compressor to the system. If you have a different size filter (3/8" is common), just change the reducer bushing and nipple coming out of the union to that size. On the branch above, I have an oiler in addition to the filter/regulator because this is the place I run most of my air tools. That saves me from having to remember to add oil drops to every tool before use. The other drops don't have an oiler.

4. I used Rector Seal #5 pipe thread sealant from Home Depot and teflon tape for every joint. I first wrapped the threads with teflon tape and then "painted" the Rector Seal over the teflon tape. I tried several variations and this way works best for me. I used a spray bottle with slightly soapy water to test all the joints and I don't get any leaks.

5. For my compressor hook-up, I just have a drop like shown above but instead of a filter, I have a short length of air hose that attaches to the reducer bushing on the union. By keeping all the drops standard, I can move the compressor or any fitting like the one with the oiler to any location in the garage I want by just disconnecting the union.

6. I have 5 drops in my system. I put the drop I plan on painting from on the last leg. My tool drop is the next to the last. When I bleed each drop, I get very little moisture after the first drop from the compressor which is the way it's supposed to work. There are fancier ways to do this but it works well for me. Some folks have a loop type arrangement at each drop where the pipe first goes up and then back around and down but I didn't have enough room against the wall plus it would add several additional joints for each drop.

Hope this helps, John.