underground air line

[bobcatdan]

Me thinking out loud here. I'm looking to move this spring and this idea popped in my head. Right now the plan is looking like looking for a place without a garage so I can build what I want. It would be basic car storage and used as a light duty shop until I build a real shop down the road. Anyways I own an 80 gallon IR compressor and what if I install in the garage and when the time comes, run a 3/4" pipe to the new building. This is northern Wisconsin so there would be frost. Is there a reason this wouldn't work? The added bonus would be I don't have to listen to it once in the new building.

 

[softailgarage]

It should work, there have been a couple of these threads in the past, I'll try to find them.

 

[2oolhound]

Yep, I remember seeing a thread on this with details, diagrams etc.

 

[OccupantRJ]

I ran 3/4" pex 100 feet to an outbuilding about six months ago. Doing great so far.

 

[sk farmer]

i wouldn't run steel pipe, corrosion and all. i would also make sure you stayed under the frostline. moisture collects in a low spot and no air til spring.

 

[jakemac]

I ran a poly line through the underground PVC electrical pipe out to my garage at my old house. I doubt that it was up to code, but it was fine for the 20yrs I lived there. As stated, as long as you stay below the frost line you should have no problems.

 

[b-body-bob]

I remember a time back when dinosaurs roamed the Earth and we had real gas stations with underground air lines to get air out to the pump islands.

I'd run it deep, like a water line.

Seems like black iron would work and last plenty long. I wouldn't be surprised if the underground natural gas line at this house (built in 1957) is black iron. Code now is to replace with plastic, but natural gas is low pressure so that won't work but surely they have a plastic alternative that would carry at least 200 psi.

 

[OccupantRJ]

i wouldn't run steel pipe, corrosion and all. i would also make sure you stayed under the frostline. moisture collects in a low spot and no air til spring.

For reference, the steel underground piping I replaced lasted for 35 years, but I decided to go with the pex to see if it will outlast me.

 

[Rookie2]

It will condense water out of the hot air from the compressor but as long as you blow it out at the far end you'll be ok.

 

[volleyball]

I'd put the compressor in the new building and run a line back if you need it. I have a 2 stage in my basement and with some isolators, you can barely hear it. I have exterior brass outlets. But I have short temp runs.
If you have it in the small building and the other building is far away, I'd go 1" or larger and a separator where it enters

 

[woody 73]

Bobcatdan I spent two years driving through your hometown and I don't miss the cold, be sure and bury it extra deep.

 

[littletoes]

When running air lines, either above or below grade, moisture must be considered, and galvanic corrosion.

Zinc is a great conductor of electricity, so it becomes an anode and corrodes. Black iron rusts on the inside as well, due to the moisture content of compressed air-hence the reason engineers oversize black-iron one full size, because in a few years the internal cross-sectional area will be cut in half due to rust.

I spend quite a bit of time replacing rusted steel lines with the only corrosion on the outside (treated heating lines-with inhibitors that prevent internal corrosion).

If your going to do it, I'd use one of the newer plastic lines rated for such...

Oh, and natural gas lines that are buried are NOT low pressure. Most residential gas lines are a minimum of 54 psi, and several are 150 psi, with mains reaching 400 psi or more.......what folks didn't know.

 

[b-body-bob]

Oh, and natural gas lines that are buried are NOT low pressure. Most residential gas lines are a minimum of 54 psi, and several are 150 psi, with mains reaching 400 psi or more.......what folks didn't know.

The ones buried after the meter/regulator that are MY responsibility are what I was talking about. Those are low pressure according the the guy from the gas company who came out when I was having what I thought was a delivery problem. IIRC he said it's about 7psi.

They came through < 10 years ago and replaced the mains in this neighborhood with plastic so I know those aren't black iron.

 

[vga]

Black iron will degrade/ rust from both inside and outside. Copper pipe, 304 or 316 stainless steel pipe would be my choice for materials. The copper piping joints will need to be brazed together to ensure being pressure rated for a compressed gas. A 30 / 60 psi blow out can kill you so its worth the time and cost to do it right. Its ok to bury threaded fittings if they are sealed correctly but never for any reason flanged connections as there is a gasket involved that will blow one day for sure. I do this for a living( design and operate 150/ 300 psi cda systems) and these are the only 3 materials I trust for HP CDA systems. Good luck with this project and be safe.

 

[DieselSaves]

We're considering mounting our compressor in an adjacent cold storage to mitigate the noise and plumbing lines into the shop. Some one told us we would have extra condensation issues because of running the air from one temp (cold storage in the winter) to the warm shop. Is this something to consider?

 

[softailgarage]

This may help a little...
http://garagejournal.com/forum/showthread.php?t=206723

 

[bobcatdan]

Thanks for the link and the suggestions. This the reason I thought of this. I was planning on just parking my big compressor for the time being and picking up a 20 gallon model. The first garage is going to be basic storage for the car, truck, mower, atv and **** like that. Overall air need is going to be very low. I would have a work bench in there and my home tools along one wall so I have a place to change oil or dink with the mower. No real hard work would be done in there. I have plans to heat the garage. I was just thinking, well what if I install the big one in the corner and down the road when I build the main shop instead of moving it and reinstalling, just run a line. This is all a thought right now since I havn't even bought a place yet to know if placement of the two buildings would make this doable. Pretty much wanted to know if this a real crazy idea before I day dream about it more.

 

[volleyball]

Has no one done anything to quiet their compressor? I have mine on a wood platform and I use a short loop of reinforced vinyl hose to isolate it. I also have convoluted foam on the wall. I've worked next to it many a time. It doesn't run long so that helps a lot.

 

[bobcatdan]

My compressor is currently in a separate room of my shop. It is mounted on rubber pucks. There is an insulted wall between the rooms and I can only hear it if the radio is off. I'm not really concern noise, it is a 24 cfm unit and runs very little. Just saw the no noise as an added bonus, not a main goal.

 

[vga]

Diesel, If you install a dryer or a coalescing filter on the outlet of your receiver the moisture within the compressed air will be removed. Without a dryer/ filter of some type downstream of the tank you will have moisture not only from dew point fallout within the run of piping due to temp changes taking place but also moisture carryover from the tank / receiver. Install a timer or float controlled auto drain onto the tanks lowest point and if possible have the air outlet connection as near the top of the tank as possible.

 

[9C1]

Some years back I returned from a vacation to find water welling up on my front lawn. My house was then about 100 years old. I thought surely it would be lead pipe and I dug it up expecting to find a way to patch it. I was surprised to find iron pipe. I am pretty sure it was original to the house and it survived nearly 100 years. I cannot tell you if it was black iron or galvanized. There wasn't enough solid to tell, but it had lasted nearly 100 years.
Terry

 

[astroracer]

My thoughts on this are: You will spending enough money to dig a trench, run air lines, put on coalescing filters and get this line plumbed, etc., etc., that you could probably buy three small compressors to do the job in your storage garage. Once you get your place bought, then have the real shop built, just move the big dude and buy a small one to fill the void.
Easy Peasy.

 

[May Pop]

The 3/4 black pipe between my 2 garages has been in the ground about a foot down over 20 years and still not leaking.