Air line ran underground?

[jarhead]

My compressor is in a shed attached to my garage. I have a pole building about 15 feet away from the shed.

Is it possible to run an airline underground to the pole barn?

I was contemplating it and was thinking moisture may get trapped in the line because it is lower and freeze in the winter,

Thoughts, solutions?

Thanks

 

[Gotcha640]

Water trap in the shed, with or without auto drain depending on your maintenance habits?

Relatively easy way to disconnect and (pour oil/antifreeze/something else) clear out?

Slope down one way or the other and have an underground service box at bottom of slope?

15 feet seems short enough you might be able to run a snake with a rag every so often.

Aside from the freezing issue, would it be worth running stainless or some other rust resistant pipe?

I'm thinking a good/easy/maybe auto drain on the tank, and robust water traps in the shed would be the way to go.

 

[rattle_snake]

Yes. It will collect water by design. Is that a problem for your application/ use?
A dryer before the underground run would solve ($$$).

 

[nh_yota]

Up here we blow out water/sprinkler lines with compressed air at the end of the season so they don't freeze. As long as you install shutoffs at each of the line and a dump valve on the far end I think you'd have no problem blowing out the condensate at the end of the season.

 

[gtr1999]

While not outside our air lines are in the concrete covering 65K sq ft. I have 1/2 taps in the floor, never had a rust issue the past 30 years.

 

[jarhead]

Thanks for comments

I am retiring in 3 months and will be in the shop most days. I need a solution that will not freeze.

I may need to move the compressor next to the shop instead. I just happen to like where it is out of the way.

I could possible bury copper and insulate it, not sure.

 

[Jeffksf]

What about running 2" conduit and just putting a hose in that, then you could easily remove the hose as needed.

 

[Gotcha640]

Finding a solution that won't freeze is different than a solution for keeping the line from bursting. How much would it be to heat trace the line?

I still think it would be interesting to do a cleanout at one end that you could open and confirm the line was dry.

 

[Red 17]

Can you go overhead? 15 feet wouldn't be a problem, and you could use galvanized pipe with air hose or copper inside it. Since it's high, drain legs at each end would be easy to deal with.

Serving suggestion....

 

[The Cobbler]

I was always going to bury a line from my shed ( compressor) to the shop. about 4' apart.
it's one of those things I've never got to yet, so I am using a 3/8 pvc airline between the 2 buildings, laying on the ground.
never once have I had a freeze. I don't think it's an issue to be concerned with

 

[larry_g]

If you go to advanced search and search the term underground and use my user name then select all threads you will find a dozen or so posts on this subject I have participated in.

lg
no neat sig line

 

[Wrench97]

I had a 3/4" copper pipe run under ground from outside compressor room to a new shop addition, we had no issues with it freezing here in Pa. If you use it daily the water won't accumulate if you are still concerned add a 1/2" water trap(less than $50) off the compressor and the line will be fine.
Another thing to consider when it's cold out there is not as much water in the air to accumulate in the compressor or the lines.

 

[Bigblockyeti]

I would bury pex and put a water separator before going under ground. Cheap & easy. If you're worried about froze water in the line, put a dryer on the line before it goes under ground.

 

[Verado1250]

I ran air to my machine shed from my shop, which is about 25 ft. I used 3/4" pex, inside 2" pvc conduit, with wide sweeps, all underground. I have a shut-off in the shop that is closed until I need air in the machine shed. If all I am doing is airing up tires, etc., then I just use it. If I'm going to use air tools, I put the nozzle on and just hold it open for a few seconds to ensure any water gets blown out. Works great. I elected not to put my compressor outside or in the machine shed due to the cold, wasp nests, mud daubers, etc.

 

[jdepiero]

Don't over think it. I ran 3/4 Black pipe 100' out to my back barn from my Main garage 35 years ago.
If i recall I trenched about 18" deep. No Issues with freezing or moisture issues. I did put a water trap in the barn. I am in North east Ohio and it gets cold here!
Semper Fi

 

[uscarry45]

All types of things are run underground water natural gas propane so it is definetly possible. I would consider the frost line in your area and soil type. I think the idea of running a hose within a pipe or conduit seems like a good idea

 

[Specracer]

If I was doing this (and I may if I get a shed for our larger blast cabinet getting it out of our building), I would use pex for the airline, and run that inside PVC conduit. And yes on water separators.

 

[OccupantRJ]

Just install a tee with a full flow ball valve where the piping enters the second building. Occasionally open the ball valve to clear out the line, and use a water separator at the air use point. If you want to get fancy, use a soleniod on a timer to blow off the line on a regular schedule.

 

[CraigStu]

It's only 15 feet so I'd be tempted to just run an air hose and lay on the ground. You could rig a quick connect that sticks out of the wall on the pole building. Have another on the side of the shed where the compressor lives along w/ a garden hose hanger. When you go out there, pull the hose off the hanger and connect it to the pole building. When you are done for the day, disconnect it and hang it on the hose hanger.

 

[coljar]

Mine runs overhead between the buildings in a steel line. It also functions as a cable tray for the Cat5/6 cable and electricity.

 

[May Pop]

Mine has been buried from house to garage for over 20 years. In Illinois it freezes and Ive never had a problem. About 20-30 feet. Galvanized 3/4 water pipe. I do wonder when it will rust away. If I had to do it again I might sleeve it with 2" electrical plastic conduit and pull in a 3/4 soft copper line. The radias of the bends should make it easy to pull.

 

[jarhead]

thanks for all the great suggestions!

it appears i was overthinking and it won't be an issue.

I will post some pictures when i get to it, i think i am going to go with the soft copper in conduit.

Thanks!

 

[bad_idea]

Might I suggest - run the line at a downward slope from the attached garage to the shed under the frost line. Where it enters the shed (underground) have it enter a sump pit. Thread a tee onto the end of the pipe in the sump pit - straight out to a ball valve for draining and straight up to go to your distribution piping. Drain the line with the ball valve into the sump pit as needed where the water can soak into the soil.

 

[BruceAz]

I’m running 1-1/4 pvc well pipe and snaking a plastic line inside it
Zero corrosion and it’s buried below the frost line

 

[Monza Harry]

JH, It will not freeze if you are below the frost line. And then that air will be cold when it exits the transfer pipe, near perfect for water separation! Just sayin' That is a plan that I executed poorly and couldn't use due to a faulty material choice [PVC (1") before I knew better, so it remains buried and never used]. That would create a nice air chiller, for water separation. For no additional cost as you need to move your air, and you want it out of sight. At 15' I would bump up one size of pipe to slow the air for additional cooling time. If you encase in conduit your cooling effect would be lost. Harry

 

[TomC750]

My underground run in upstate NY was 60'. Only had a moisture separator at the end in my shop. Nice to not hear compressor run. No problem with freezing. Line was PEX, 3/4.
Tom

 

[Firebrick43]

Second Monza Harry. Below frost depth your golden.

 

[jonesg]

i bought a rapidair kit with manifold and 3 outlets for the garage, buried the pipe 3 inches down, no conduit, no air dryer, the manifold in the garage has a blow-off valve to blast it out. 3 years no problem. it gets cold in northern maine. 9F last night.
keep it simple.

 

[jarhead]

thanks for all the great suggestions!

it appears i was overthinking and it won't be an issue.

I will post some pictures when i get to it, i think i am going to go with the soft copper in conduit.

Thanks!

well i totally forgot about this question. Since it came back up here is what i did, i ran copper.

 

[Renegade1LI]

I'd run 1" sch 40 black, domestic, bury it 24" , tee and valve to blow off. Keep it simple, avoid running copper in steel conduit.

 

[Renegade1LI]

If you decide to use copper don't forget to use dielectric fittings where you connect back to steel.

 

[speed bump]

All of our shop buildings at work are fed by steel lines buried two feet down. Never had an issue with the lines freezing even in the nastiest winters.

Lines not buried definitely have more issues even with heat tracing and insulation.

 

[sparkness]

I used pex pipe and ran it thru sprinkler poly pipe and trap the water before it gets into my tank,

 

[The Cobbler]

I've had a 3/8" PVC air line laying on the ground from my compressor in the shed to the garage for several years with no problems

 

[GrayFlattop]

I ran 1/2" DOT air brake tubing inside of 1-1/2 PVC in case I ever had to replace the line.

Never a failure in 30+ years.