Copper Air Lines?

looch · Dec 13, 2001

I'm trying to save some space in my garage by moving my air compressor to the second floor. At the same time, I would like install some plumbing - basically just 2 or three couplers at convenient locations. What material could I use for the plumbing? I was thinking of using copper pipe - just not sure of what grade. I think this would be the simplest solution as far as tools go. How would you do it?

Mike_Dumond · Dec 13, 2001

1/2 inch 'L' copper pipe, not tubing, should get you what you need. Don't use the 'M' pipe, it has a thin wall.

Keep the greasy side down.
Mike

Youare · Dec 13, 2001

As Mike has said "L" grade copper tubing. Someone installed steel pipe where I work years ago. When a little moisture got in the lines when our air drier died we ended up with rust flakes in the lines. Copper is the way to go.

Randy

Bird · Dec 13, 2001

Paul, I'll agree with the other guys. And of course, all the "experts" say to not use PVC, but schedule 40 half inch PVC is what I (and a lot of other people) used.

PitbullMidwest · Dec 13, 2001

We used schedule 40 as air lines at work and they worked fine until the pressure relief failed on the compressor and exploded the line. Everyone was at lunch, luckily and no one was injured. If production was running the shrapnel could have very easily killed someone.

IMHO no one should use schedule 40 as air line.

Jeff396 · Dec 13, 2001

I installed steel pipe at the last two houses I lived in and would like to avoid that nightmare if I can in my new house. I'm not familar with copper "L" pipe. How do you put it together and is it somewhat flexible eliminating all of the elbows during installation? What kinda pressure can you put through it? I'm looking to do this in the spring and would definatly like an easier installation process.

Jeff

MJB · Dec 13, 2001

I have seen type L copper, also known around here as ACR copper, in both soft and hard types. The soft variety can be easily bent with a tubing bender or by hand if you are not too fussy about appearance. We use large quantities of copper tubing here at work for building air conditioning compressor load test stands and calorimeters. I don't have the data right here in front of me but I am sure that ACR copper can handle several hundred PSI without any trouble. The smaller sizes have burst ratings in the several thousand PSI range. You should use silver solder to sweat the fittings together for maximum strength. Any air-conditioning and refrigeration supply house can provide you with the necessary materials. Hope this helps.

72% of all statistics are made up./w3tcompact/icons/smile.gif

looch · Dec 13, 2001

Thanks guys. Should I be able to pick up L grade at the local home centre?

rdln · Dec 13, 2001

check out http://www.sharpe1.com/dr-pipe.htm
for helpful diagrams.

The farmers at another forum I frequent are always
debating PVC/CU air lines, one of them said OSHA shuts down
shops with exposed PVC lines.

Steve
Champagne Taste, Beer Budget

DocHeb · Dec 13, 2001

I usually overdo things, but copper over PVC is not overkill. The PVC will fracture with explosive force with minimal trauma when it is under pressure, especially if it is cold. The L type is connected with the typical solder/sweat fittings found at the store.

My compressor is in the basement, with copper lines in the workshop and out to the garage. I wired a pair of three way switches in the shop and garage that run to a motor contacter (a 120vAC coil driving a "Normally Open" 240vAC, 20Amp relay) that allows me to turn the compressor off and on from either location. I also plumbed a "Normally Open" solenoid in place of the drain valve so the air is let out of the tank when the AC is disconnected by the three way switches. This drains out the compressed air and the accumulated water that can rust the tank and lead to premature failure. I got the motor contacter and the solenoid from Grainger. The nice thing is this distant location is really quiet since the compressor is not in the work area, but in a side room.

dummy · Dec 14, 2001

Great idea on using the normally open solenoid for the drain line. Thanks

Boondox · Dec 14, 2001

DocHeb has some great ideas! I shoulda done that! One thing I did do right is hanging the copper with a slight slope so all moisture condensed and ran away from the compressor to a drain valve.

Pete

www.GatewayToVermont.com

Anonymous Poster · Dec 14, 2001

Refridgeration copper is built to withstand far greater shock loads than your air lines will ever see. Use soft silver solder on the fittings and you're good to 400psi.
When using copper for compressed air, make damn sure your lines have plenty of pitch and are thoroughly drained when conditions go below freezing, or you'll find plenty of buldges and splits.
Also make sure to use vibration mounts on the compressor if it's in the attic, or learn to like drum music.
An outside air intake will also reduce noise in the shop, and compressor life will be extended.

frank_f15 · Dec 16, 2001

a little late on this thread but, here is my .02 worth. if u are going to use copper, then type L at min. type k if u really want to be safe. use silver solder or phos copper as soldering medium and be sure to use a condensate drain at point of use. water will paly havoc with certain air operated tools.also use a fexible connector bet, compressor and pipeing, a ruptured air line can be very dangerous, just the sound can hurt your hearing.

Paul_in_CT · Dec 16, 2001

Guys I`m getting ready to install radiant floor heat in my first floor.When I went to pick up the tubing I notticed some blue tubing they had. They use it for air lines also can be used for water lines. Not sure on the spec but could find out. I just used some of the orange radiant tubing to pipe in my buddy`s radiators. Much easier and quicker than copper. If I ever build my garage I planned on looking into it further. Here`s the link to the stuff. American radiant is who I bought from they are down to earth guys and have always been honest when answering any questions.
http://www.americanradiant.com/kitec.htm

Anonymous Poster · Dec 17, 2001

Plastic has been used for just about every air line on every truck made in America for the last 20 years. The big bugaboo about plastic air lines got started cause some fool used cheap plastic from some home center, and blew the line.
Like anything, the skill ain't in the material, it's in the mechanic. Fittings for plastic tubing usually run the cost above using copper and soldering it. R-22 runs at head pressures of 300# and has thermal shock to contend with that make an air system look like a kids baloon, yet R-22 systems run every day in copper with silflos joynts.
Seems like most air systems I see are plumbed with undersize pipe cause the guy who installed it never heard of fluid resistance in a line.
Bottom line, if you don't know what you're doing, leave the job alone.

jdrotert · Dec 17, 2001

I've been lurking in the wings on this thread just trying to pick up some info. I purchased a house with a detached 3-bay shed last May. The shed came with a 60-gallon compressor (woo hoo!!!). There's all but no plumbing for air in the shed. I'd like to run piping for 3 or 4 outlets around the shed along with one outside. Copper seems the way to go. What would a good rule of thumb be for pipe size. It looks like I'll need at least the type L kind, but what size. My longest run will be around 100 feet. Would 1/2 inch be good enough for this kind of run?

Bird · Dec 17, 2001

I'm going to guess you don't have any really BIG air tools that require a lot of volume and since most use 3/8" inlets, then 1/2" lines should be plenty. I don't have any runs with my permanent 1/2" air lines more than about 30', but I sometimes hook up 150' of 3/8" air hoses to one of them./w3tcompact/icons/wink.gif

Boner · Dec 17, 2001

I have always used lead free solder (not sure of specific type) for plumbing H20. Does anybody know what is the max psi for for standard lead free solder joints?