# Adding Copper Lines on Compressed Air Supply to Remove Water?



## Crashcup (Feb 11, 2015)

Hi, I was reading some forum posts about compressed air supply in the shop, and thinking ahead a bit on how I want to approach this in my basement shop.

I was considering two possible places to store the compressor to keep it out of the way - one under some steps, and the other in an adjacent utility room. When I read some posts about removing water from the air lines, I realized two things: One, the area I was considering in the utility room is close to a floor drain, which may be convenient for draining condensate. Two, I have scrap copper pipes - mostly 3/4" - from replacing our previous hot-water heat with a force-air system. I'm hanging on to the copper to sell for scrap, but if I can get some benefit out of re-using it myself, all the better!

The diagram attached is what I am envisioning. A series of 3/4" copper pipes going up the wall, where the air could cool and the condensed water run down to a drain. I would probably run the copper over the wall and into the shop, and then convert over to the Rapidair piping to distribute air around the shop.

Finally, my question. I'm wondering if someone here has done something similar and can comment on how effective this might be. If this just isn't going to remove much water, then I don't want to waste my time and the copper. Or, if just a couple of lengths of the copper would remove a good portion of the water, then something like the 9 lengths I showed in the diagram might be overkill. Without getting into a bunch of equations, I just don't know how to get an idea whether this would be worthwhile.

*One thing I just realized looking at the diagram again: I have to add a drip leg below the Tee shows, and have the valve off that. As shown, it wouldn't have anywhere for the liquid water to go and would be pushing it forward through the lines.*

Seems like there's a lot of variables to consider. Two things I can say is that this being a basement in an air-conditioned house, the air temp should always be in the 68 to 82 degree range, and the humidity should be in a reasonable range, probably 40-50%.

Anyone?

Thanks,
Keith


----------



## CecilD (Jan 6, 2009)

Most of the water will build up in the compressor tank so be sure to add a drain to the bottom of the tank. I put a tee at each outlet with a drop leg as well as at the compressor. I installed ball valves on each of the drops. So far no problems (3yr.) with the system. I am in mid Missouri and I do keep some heat on in the winter. (mid 40's to 50's)


----------



## tomsteve (Jan 23, 2015)

id suggest taking the zig zag down the wall and turning them 90 degrees with a drain at the bottom of each run like so


----------



## TheFridge (May 1, 2014)

Or buy a dryer.


----------



## johnstoneb (Jun 14, 2012)

Your moisture will be in the tank. you need to drain the tank often. and have traps and at each drop. If you are really hav ing trouble with moisture add a filter and dryer.


----------



## Crashcup (Feb 11, 2015)

> Most of the water will build up in the compressor tank so be sure to add a drain to the bottom of the tank. I put a tee at each outlet with a drop leg as well as at the compressor. I installed ball valves on each of the drops. So far no problems (3yr.) with the system. I am in mid Missouri and I do keep some heat on in the winter. (mid 40 s to 50 s)
> 
> - CecilD


Yeah, I have one of those auto-drain valves from Northern Tool. It opens when the unloader valve opens as the compressor shuts off. I'll be able to run a small line from the auto-drain valve to the floor drain. Never used one of those before, so we'll see how well this keeps water out of the tank.


----------



## Crashcup (Feb 11, 2015)

> id suggest taking the zig zag down the wall and turning them 90 degrees with a drain at the bottom of each run like so
> 
> 
> 
> ...


----------



## Crashcup (Feb 11, 2015)

> Your moisture will be in the tank. you need to drain the tank often. and have traps and at each drop. If you are really hav ing trouble with moisture add a filter and dryer.
> 
> - johnstoneb


Thanks for the replies. I should have mentioned that I've never done any spray finishing. I'm only thinking about removing some of the water thinking it'll be better in the long run for air nailers… brad nailer and pin nailer.

Someday if I want to try spraying finish, that'll be a whole different ball of wax. Then I might have to look into something like this + dryer.


----------



## MrUnix (May 18, 2012)

> Or buy a dryer.
> 
> - TheFridge


<grin>

That's what I did.. nothing fancy.. think it was about $8 or so. Includes a filter as well.

I've used my compressor for spraying all types of finishes, sand blasting, pneumatic tools and just about everything else you can use a compressor for - and never had a moisture problem. And I'm in FL where on a good day we might get down to 70% RH 

Cheers,
Brad


----------



## tomsteve (Jan 23, 2015)

> id suggest taking the zig zag down the wall and turning them 90 degrees with a drain at the bottom of each run like so
> 
> 
> 
> ...


i got into auto body repair and was running a lot of air tools along with spray guns. thatsetup, plus this at the end

http://www.autobodytoolmart.com/devilbiss-finishline-120cfm-air-line-filter-50cfm-regulator-har-602-p-14418.aspx

kept my air not only moisture free but also cool. this was off of a 60 gal compressor. only difference was i ran down the wall and back up with 4 runs so filter was at the top of last run.. i used 3/4" copper.
when clearing out id have moisture at the first 2 and the last would only have moisture if i wa working on warm humid days or forgot to drain them for a while. the devilbiss filter did a great job,too. i never had a moisture problem in paint.

you might alsowant to look up "franzinator" for another option.


----------



## tomsteve (Jan 23, 2015)

oh, each verticle run was 3'4"(3 runs from a 10' piece) and middle horizontals were long enough for the drain, short sections of 3/4" to hook to elbows.


----------



## Crashcup (Feb 11, 2015)

Thanks Tom. I think I have a plan now. I guess it makes sense that the vertical runs would work better - using gravity to help pull the liquid water down.

How long are the drops between the tees and the drain valves?









I also may use some of these instead of bare pipe. These are the cores of the radiators from the hydronic heat system we took out. With the extra surface area of the fins, it may be even better at transferring heat out of the compressed air.

I think I'll just start with the "aftercooler" - that will remove a lot of the water and should fine just for using a nailer. Plus I plan to have air to 3 different places in the shop so I don't have to run long hoses, and that would triple the cost of filter/driers if I want them at point of use. Later, if I start spraying finishes, I can re-evaluate.

Keith


----------



## tomsteve (Jan 23, 2015)

ive seen people use those. say they work great. gotta get the heat out along with the moisture.
on mine the verticles were only 40" to get 3 from a 10' section of pipe. i dont think theres a set length they need to be. whatever works for ya.

one thing i also did when spraying vehicles-when the compressor would run a bit long- was leave the drain on the compressor cracked open justa bit to drain any moisture from the tank.

reads like ya have a good plan going.

helluva drill press ya have!


----------



## Redoak49 (Dec 15, 2012)

I would be cautious about reusing copper pipe fora pressure system. Water pipe is is typically thin wall and not rated for compressed air.


----------



## Crashcup (Feb 11, 2015)

> I would be cautious about reusing copper pipe fora pressure system. Water pipe is is typically thin wall and not rated for compressed air.
> 
> - Redoak49


I was wondering about that. I googled pressure ratings, and found this:
http://www.copper.org/publications/pub_list/pdf/copper_tube_handbook.pdf
Even the thinnest drawn pipe, type M, is rated for 680 psi according to this.

As long as the pipe doesn't have any pinholes should be good. But if it fails, it would split, right? Wouldn't shatter like pvc.


----------



## tomsteve (Jan 23, 2015)

your compressor shouldnt be more that 150 psi. it will split if it fails.


----------



## tomsteve (Jan 23, 2015)

i will add it would be wise to inspect the inside of the piping. copper pipe can corrode internally. if theres a buildup of any kind in them id be leary of using them.


----------



## sawdust703 (Jul 6, 2014)

Well, first off, I don't see the need for all the zigzag design in your thinking. The straighter line air can run, the better. IMO. Moisture will settle to the lowest point in the system, & depending on your weather conditions, meaning humid or dry, etc., you're going to have more moisture in humid conditions than you will in a drier climate. Moisture will prevail in any air system because of the heating & cooling of the air in the system. Our brake systems on our semis, for instance, use air. And yes, there is an inline dryer at the lowest point possible. Usually mounted on the frame on the left front side, below the compressor. You've heard the air valve pop on trucks when pressure is reached in the system, I'm sure. That air you're hearing is coming from the relief valve at the dryer. The reason for that is to keep the dryer emptied thru that pop off valve. Now, there are 3 - 5 other air tanks in the same system, all with drains. Whether it be a turn valve, or a pull valve on a cable. Those will all collect moisture daily. Simply because of their location. They can be drained at anytime, & you'll see moisture on the ground. The air lines we use are steel & high pressure rubber lines, with brass fittings. My point of all this is, were I you, I'd avoid using copper at all cost. It corrodes easily, has a short work life, & even though your system is running 125 - 150 psi max, if there's a weak spot inline, it will explode. Were I you, depending on how far you're going to run air line, I would could consider PVC pipe. It seals at every joint, & is easier to work with. And lasts longer, too. My airline is 3/8" air line run directly from the compressor, up the wall, & along the ceiling in the shop for about 30', & drops right down to my work area. I don't feel I need anything any bigger because of the distance, and I've got all the pressure I need at the work end of the hose. I've got longer hose add ons if I need them. And they are made of 1/2" rubber hose. JMHO.


----------



## tomsteve (Jan 23, 2015)

DO NOT USE PVC!!!!

http://www.aircompressorworks.com/blog/index.php?mode=post&id=34

http://forum.eastwood.com/showthread.php?5861-PVC-air-lines-are-deadly!!

MANY instances out there of pvc explosions causing serious injuries.

COPPER AND COPPER ALLOYS are widely used in many environments and applications because of their excellent corrosion resistance, which is coupled with combinations of other desirable properties, such as superior electrical and thermal conductivity, ease of fabricating and joining, wide range of attainable mechanical properties, and resistance to biofouling.

Copper corrodes at negligible rates in unpolluted air, water, and deaerated nonoxidizing acids. Copper alloy artifacts have been found in nearly pristine condition after having been buried in the earth for thousands of years, and copper roofing in rural atmospheres has been found to corrode at rates of less than 0.4 mm in 200 years.


----------



## Knothead62 (Apr 17, 2010)

I recall seeing a water trap like the old cars had- a sediment bowl that was glass. Of course, you didn't have high pressures that you are looking at. You removed the sediment bowl and cleaned out the water and crud. I think heavy equipment and farm equipment still use them. They are better than the inline filters we have now. No matter what you do, good luck. Let us know how you tackled the problem.


----------



## Capefisherman (Dec 23, 2020)

Ive worked and designed hydraulic ans pneumatic systems for years. The only way to remove moisture is a dryer. I guess the question is: What is the end use of the air? Spraying or nailers? Most likey you can just use a simple in-line filter. They are cheap and work well. Get one with an auto drain. Place as close to the end of the line as possible. DO NOT USE PVC PIPING!!!! And, I'd stay away from using copper. Pipe with black iron pipe. And drain your tanks daily.


----------



## ibewjon (Oct 2, 2010)

I would buy a drier. Cheap and small. Save the wall space and scrap the copper to pay for the drier and some more shop supplies. Why did you replace the hydronic heat? It is the best system out there.


----------



## them700project (Aug 12, 2015)

Dryer would be best but keeping to your original sketch. You could use a hot water coil Baseboard radiant is not great it is super thin wall but most heating coils are thicker with brazed joints. (probably find at the scrapyard.) feed the top of it then all your back and forth action would be completed by the coil.


----------



## PCDub (Sep 24, 2017)

[guys… 6 year old post. The OP has already done whatever he did!]


----------



## kelvancra (May 4, 2010)

I'd always been taught to run lines at a slight down angle away from the compressor, and to add a simple drop at each outlet, with a valve, to bleed moisture.

My system will have a trap on each outlet. After all, if you're putting a real compressed air system in, you're already nearly broke, so you might as well spend what little you have left on traps.

ALL THAT SAID, I like the design I've seen above. I think I could switch in a still (condensation) system and REALLY have fun in the shop.


----------



## tvrgeek (Nov 19, 2013)

It is called a "condenser" Works well. Do be careful to get pipe schedule with enough safety margin. 
This would make a great one: 
https://www.homedepot.com/p/Everbilt-1-2-in-x-20-ft-Type-L-Soft-Copper-Coil-Tubing-1-2-L-20RE/203654563
Does not to be spread much, just enough to drain.

High end shops have heat-pump driers to really chill the air. You get the moisture out BY reducing the temperature. Physics 101. 
The most effective location is between the pump and the tank as the air is the hottest. Then the tank can be the accumulator and it has the drain cock. You still should use an inline desiccant when spraying finishes.


----------

