Underground air line to barn

[sawduster98]

Has anyone run compressed air underground? My barn is 85' from my shop where the compressor is and since I'm about to run electric out there I figured I'd ask the question. I don't know if it's feasible and I don't remember hearing of anyone that's done it. Thanks

 

[MotorSeven]

I don't see why you couldn't...air line is cheap enough. I think I'd sleeve it into a 1" pvc pipe. That way if it ever fails just pull it out and slide a new one in. You could use the cheaper lightweight schedule 40 stuff.

 

[MillWeld]

I agree with Motor. Also install a secondary tank in the barn so you don't get a huge pressure drop. But you probably already know that.

 

[MotorSeven]

MW I don't think 85' would show any drop. I've used up to 300' of line on a pancake compressor air nailing fence...no issues at all.

 

[RickB]

Probably more trouble and cost than it's worth. Condensation will collect in the low spots. For the cost of the line (and certainly a line that is sleeved) you can buy a small compressor to have in the barn for tire inflation, etc. If you do run a line, 3/4" is the minumum I would consider and you won't sleeve that with 1" anything.

 

[MotorSeven]

Good point on condensation, but if he get's a 100 foot hose it will have no connectors to rust/corrode. He doesn't have to sleeve it, could just chuck it into the trench and I bet it would last for a decade or more.

 

[RickB]

Good point on condensation, but if he get's a 100 foot hose it will have no connectors to rust/corrode. He doesn't have to sleeve it, could just chuck it into the trench and I bet it would last for a decade or more.

100' of 3/4" hose or 1/2" hose with a balance tank will still cost as much or more than a small oil-type compressor.

There's all kinds of ways to do what the OP is asking. Some of us think it is a good idea, it just happens that I don't. You bury $150-$200 worth of lines & fittings, that's pretty much the only place you can use it. A small 110V compressor can sit in the barn and inflate tires, etc. and when it is needed somewhere else, it can go.

 

[Kays Supply]

For what it's worth, 3\4" PEX is .75 a foot. It is only rated to 100# @ 100+ degrees. But PVC isn't rated that high at that temp.

 

[sawduster98]

Good points brought up...I hadn't considered condensation even though I'd trap and filter the line at the barn. I already have a small portable unit but it won't handle sanders and HVLP sprayers. It sounds like it's probably not worth the cost for the amount of time I'd really need it so maybe I'm better off buying a long hose or 2 to reach out there when needed.

 

[mwb]

I would bury a 4" Big-O (tile drain stuff) and pull a line through. You would also have room for other services, alarm wire, phone, water. It would be so easy to have a shut off valve at the source, leave the buried line unused until you need it. The only additional cost would be the cost of the Big-O. Be aware that the larger line would also be a conduit for mice, etc so plug the ends.

If you want to run impact or other high volume tools then you would need a tank at your barn. For your HVLP you could run full pressure in standard 3/8 line to the barn and use a regulator there to give you the pressure you want, you wouldn't need a ballast tank. Probably cost you $60 for the drain + airline, and a shut off valve - $100 total? You are ONLY going 85 feet, my air line is 100' and I have painted cars with no problem. For $60 you could bury the pipe, if you opted not to use it then you are out $60. While you have an open trench I think you would be crazy not to install it!

 

[Travelover]

I'd just pop for a small compressor like this one. Goes on sale for less than $100 all the time.

Portable Air Compressor - 2 HP, 8 Gallon, 125 PSI

 

[EddieWalker]

How often do you need air at that location? I have a hundred foot hose that I keep outside on a garden hose real that I just unwind when I need it. Depending on where I'm working, I just unroll it and leave it lay on the ground until I'm done with it. Sometimes it's just a minute that I need it, other times, it's laying on the ground for a week or more.

If it ever breaks or needs replacing, I just buy a new one. No trenches, nothing to mess with and I'm ready to go in minutes.

Eddie

 

[hizoot]

Years ago, I buried 3/4 " heavy wall pipe from my storage shed to my shop,about 80-100'. I did this mainly to get rid of the noise.Also, installed a 3 way switch that I could turn it on remotely. It turned out,the condensation was too much. Line filled with water regularly. I tried all kinds of ways to cool the air before going underground,but it didnt work. I guess the ground being cool would invariably condense the air,especially in winter. I gave up,moved the compressor into my shop and built a sound deadening enclosure.

 

[BeezFun]

You could put in 1" poly plastic line like they use for wells. I just bought 100' for $25 at Tractor Supply, it's rated 160 psi. Menards also sells it. Easy to step down at each end to standard pipe fittings. Wouldn't be any pressure drop over that distance, and it's made to be buried. They also make 200psi for a bit more money. I think there's even less expensive stuff that isn't approved for drinking water.

 

[dex3361]

I ran a 1.5' black PE pipe from the house to the garage fortunately my pipe is downhill all the way and the condensate is easy to drain off. I think the PE pipe is rated for 160# and is cheap. if you force a low spot and install a tee with a valve to blow off the condensate then you could keep it drained. Probably more trouble than its worth but it can be done.

 

[rjmack]

i have a compressor on a 60 gallon tank. i just left the shipping pallet attached. it's easy to move with forks on the loader bucket. all that's needed is a 240v plug in whatever building you want to use it.

 

[ultrarunner]

A few years ago I ran coiled copper 3/4 a few hundred feet underground and condensation has not been a problem because the air goes through a dryer first.

I also added an automatic condensate valve to the compressor that cycles every couple of hours...

 

[mjncad]

A few years ago I ran coiled copper 3/4 a few hundred feet underground and condensation has not been a problem because the air goes through a dryer first.

I also added an automatic condensate valve to the compressor that cycles every couple of hours...

I was going to suggest 3/4" type K soft copper pipe. Type K is the heaviest wall of the three grades of copper.

I guess it depends on whether the OP wants to wrestle with a hose on a reel now and then, have a second compressor, or have something buried.

 

[hizoot]

A few years ago I ran coiled copper 3/4 a few hundred feet underground and condensation has not been a problem because the air goes through a dryer first.

I also added an automatic condensate valve to the compressor that cycles every couple of hours...

Is the drier a refrigerated air cooler? What is the typical humidity in your area? 3/4" heavy wall copper is approximately 200.oo+ for 50' now....At least the refrigeration tubing is,haven't priced heavy walled water copper.

 

[ultrarunner]

Is the drier a refrigerated air cooler? What is the typical humidity in your area? 3/4" heavy wall copper is approximately 200.oo+ for 50' now....At least the refrigeration tubing is,haven't priced heavy walled water copper.

Humidity varies... average is about 50%... can be much drier for short periods or much more humid when the fog comes in.

I picked the drier and compressor up together from Grainger in 1998...

I has refrigeration coils and and a float condensation valve and the compressor has an automatic tank drain.

The only time I had any moisture at the end of the line was when the drier float froze and preventing the condensate from draining.

Copper has never been cheap... best guess was about $1.40 a foot...

I think the coils were 60' lengths.