Plumb the garage for compressed air

[LEVE]

My harebrained idea last week end was to plumb my three car garage with four areas to access compressed air. I have a 15 year old 25 gal 5 horse Craftsman upright compressor built into a sound-deadening compartment under my workbench. I hate having air hoses laying all over the floor. My solution has been to take that white 1" ABS pluming pipe and run it up and across the ceiling to the two garage door rail supports. Then the pipe runs down the pipe to air-hose bibs that hang down just low enough for me to attach a hose.

The ABS pipe has a 200psi rating and my compressor is only good up to 120psi. I normally run it at about 60psi. The weakest part of the project is the joints. I did a small experiment with a 3' section plumbed with input and outputs for hoses and pressurized it to 120psi for several hours. It held the air with no leaks or problems.

The pipe is being held to the wall and ceiling by making "clips" out of 3/4" ABS, drilled and screwed to the wall/ceiling. This lets me just snap the pipe into place. Works like a charm.

The downside? Well, if you're tall you may hit the hose-couplers if you're not looking... the pipe will be painted florescent orange as a warning. here's one shot of the middle drop, during construction. It should be finished this afternoon.

[zmotorsports]

I personally would be a little leary of the PVC's durability. I know it is rated @ 200 PSI but just not enough of a margin of safety for me. I have used copper tubing and gas pipe with great success. If you haven't completed it yet I would recommend using copper. Mike.

[LEVE]

Good call on the copper and gas pipe. I hadn't thought of that. I'm am a little leery of temperature, as I know the pipe can become brittle in the cold.

[Torque1st]

ABS pipe is black. PVC is white. Under NO circumstances should you use standard ABS or PVC for compressed air.

The "pressure rating" is for water or liquids under pressure which is ENTIRELY different from pressurized gasses like air.

There is one type of ABS that is allowed to be used with compressed air but it is very expensive and a special order product. It is clearly marked for use with compressed air. I have not seen any for years.

PVC is a big NO NO for compressed air. This has been discussed here ad nauseam because of harebrained ideas.

[larry_g]

What TQ! said. There are books and an internet full of the dangers of PVC in an air system.

lg
no neat sig line

[drmoonshine]

It's aesthetically pleasing by taking the hose out of eyesight but there is a big safety concern with ratings for PVC with compressed air. Good Luck on the project.

[fflintstone]

The general consensus is black pipe good, PVC (or other plastics) bad. I tend to agree. There are many examples of PVC working great for many years than having catastrophic failures. Since you have already done this I would think about replacing it in 5 years. (Less if your garage gets very cold in the winter). In a year or two you may want more or less outlets and a different layout.
ALWAYS use a short length of flexible hose between your compressor and your manifold system.

[ddawg16]

Leve.....the guys are being gently on you......do a search on PVC and you will see a ton of posts on the subject.

I did mine in copper....easier since I was puting mine in the walls and ceiling....easier to sweat pipe than thread it.

May I suggest that you raise the coupling up and use one of those yellow coiled hoses? I have one above my radial arm saw....up high enough to be out of the way...when I need it....I just reach up and take it off the hook....I'm thinking about putting a spring on it.

[LEVE]

Hi John, yeah, these guys are being civil aren't they!

Prior to starting the project I've did some research on the burst strength of the pipe, as well as the rating of the Schedule 40 and the relationship to the bust and the diameter. So far.. so good. I should have searched on this forum, but being basically lazy, I didn't.

I'll complete the project today and give it a try for a year, or so, and see what happens. I do like the idea of copper pipe, it's easy to work with and lasts forever. I do plan on using a coiled hose near the workbench... but at my height... the drops near the garage door will stay unless the Jeep or the Astro can't get under 'em.

[rickycobra]

I worry about putting compressed air through the walls because of two reason the pvc could break and damage the walls and leaks would be harder to find. What if you just had to air compressors or is that be too lazy? However, it will keep the garage organized.

[ddawg16]

Like the guys said above....a bigger issue is if you run into it....strength wise, yea....it can handle the pressure alone....but garage rash? It won't take much to break it...

To confirm....same Leve from SWB? If so....it's all your fault for me killing so much time over here......

[larry_g]

I bought some PVC the other day for a water project and it has printed right on it "not for compressed air" Its in the ground now but I did find the other pipe rated for water, see picture. In its out of focus it says 370psi PR WATER. What does it say on your piping LEVE. Read it and then go look up the spec it refers to. Make an informed decision as to why you are putting yourself and family at risk.

lg
no neat sig line

[Stuart in MN]

The pressure rating printed on the pipe is for noncompressible fluids, not gases. The big issue is PVC is not ductile, like copper or iron pipe - if it is damaged, the compressed air inside will rapidly expand, shattering the pipe and throwing shrapnel all over the room. If this happens to copper or iron, the pipe simply bends instead of breaking like PVC.

[jeffk14]

Flame suit on: I have a PVC line run from my compressor that's in the basement (which is not subject to freezing) to the garage. It's about a 40 foot run. The PVC terminates just inside the heated space and regular air hose runs through the sill, out into the garage. The PVC runs along the bottom of the floor joists at the top of a 9 foot unfinished basement. The line never sees over 90 PSI.

It's been there for 17 years. Works fine. If you're nervous and want to use PVC, wrap it in heavy foam pipe insulation. That way, if it shatters, the "schrapnel" won't fly everywhere. I would not use PVC where freezing is a concern though. The stuff does get brittle when cold.

I will edit to add that I'm also using an oil-less compressor, so there's no oil residue in the line to potentially attack the PVC chemically over time. I'll also add that the PVC is isolated from the compressor vibration-wise by a short run of regular air hose that runs from the compressor to where the PVC commences. My PVC run is also in a place where it is not subject to mechanical damage. YMMV.

[Torque1st]

Jeff-

PVC is always brittle regardless of the temperature. That is why it should not be used for compressed gas. Even the manufacturers (which would love to sell more PVC) state that it must not be used for compressed gasses. They do not even allow leak testing with compressed air. Check their websites and technical literature (LEVE should have done this). Foam will not prevent shrapnel from flying when the pipe explodes. 17 years or not, -you have a ticking time bomb in your garage.

[jeffk14]

Originally Posted by Torque1st

Jeff-

PVC is always brittle regardless of the temperature. That is why it should not be used for compressed gas. Even the manufacturers (which would love to sell more PVC) state that it must not be used for compressed gasses. They do not even allow leak testing with compressed air. Check their websites and technical literature (LEVE should have done this). Foam will not prevent shrapnel from flying when the pipe explodes. 17 years or not, -you have a ticking time bomb in your garage.

I'll give you a little history. Originally, the PVC ran all the way through the sill into the garage. One day, I was in the (freezing cold at the time) garage and bumped into the QD fitting hanging off of the end of the PVC. It was under pressure and did shatter, but it was not a bomb by any means. It startled me and I would not have wanted my eyeball up against it but nothing flew very far or launched in a ballistic manner.

My fix was to terminate the PVC on the other side of the sill where it couldn't be bumped and wouldn't be exposed to freezing temps.

I know PVC is not rated for compressed gases. I know it MAY fail. I also know that in MY installation, there is no safety risk if it DOES fail.

[Torque1st]

You got lucky. Don't push your luck.

I have seen it explode and throw slivers of plastic all over a shop. Some were embedded in walls. There was nothing to mechanically damage the pipe. It happened in the middle of the night in a warm shop and the compressor was not even on. It just had residual pressure in the line.

Do NOT use PVC for compressed air unless it is buried in the ground and protected by encasing in steel pipe in exposed locations.

Some people feel they are safe. -Unfortunately the wife & kids, neighbors and friends are also at risk. Lawyers just love to sue people for negligence.

[jeffk14]

Originally Posted by Torque1st

You got lucky. Don't push your luck.

I have seen it explode and throw slivers of plastic all over a shop. Some were embedded in walls. There was nothing to mechanically damage the pipe. It happened in the middle of the night in a warm shop and the compressor was not even on. It just had residual pressure in the line.

Do NOT use PVC for compressed air unless it is buried in the ground and protected by encasing in steel pipe in exposed locations.

Some people feel they are safe. -Unfortunately the wife & kids, neighbors and friends are also at risk. Lawyers just love to sue people for negligence.

What kind of pressure was on that pipe? I'm not saying it didn't happen, it's just hard to believe that 90 PSI (which is what I run) could do anywhere near that much damage.

[Grigg]

Try this link
http://www.osha.gov/dts/hib/hib_data/hib19880520.html

I know many folks don't care for OSHA, but when the manufacturer(s) of the pipe and OSHA both agree that it's not to be used for compressed air we should listen.

Grigg

[PontiacFan]

Transair-usa.com
PM to me if you need some, I've done many projects out here with it & love it.
Not nearly as cost effective as PVC, (Which really isn't legal.), but you cna install in a matter of hours!

(Yes, private labeled also as Garage-Pak, but I don't deal that tradename. You can buy it online there tho.)