# Testing 2" copper



## guyute65045 (Nov 23, 2006)

I have to test my 2" copper feed line to a water tank before a slab gets poured next week and the GC's foreman just told me that it had to be tested at 250psi for 2 hours with no leakage? I have never tested copper at that pressure before, I would be hesitant to trust the lower end compression fitting as it is in a finished basement. There is nothing mentioned in the spec book about testing of this line, and it will take weeks to get an answer from these engineers.
Anybody have experience with this pressure or is the guy just smokin crack? I tested the return line from the same tank using NFPA 13 code, but that was 6" ductile. Operating pressure will be 60psi, and there are 3 Mueller inline couplers from building to tank. 
Thanks,
John


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## Anti-wingnut (Mar 12, 2009)

Well, if you do go to 250 psi, water test it, not air. I used to work at a ASME pressure vessel fabricator, and we had to test all our tanks. A failure with air is really dangerous, because of the compressibility of air. Because water is not (really) compressible, a failure does not result in shrapnel.

A pressure washer is the tool of choice to bring the pipe up to head.

That said, I would want someone to prove that it needs 250 psi


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## griz (Nov 26, 2009)

guyute65045 said:


> I have to test my 2" copper feed line to a water tank before a slab gets poured next week and the GC's foreman just told me that it had to be tested at 250psi for 2 hours with no leakage? I have never tested copper at that pressure before, I would be hesitant to trust the lower end compression fitting as it is in a finished basement. There is nothing mentioned in the spec book about testing of this line, and it will take weeks to get an answer from these engineers.
> Anybody have experience with this pressure or is the guy just smokin crack? I tested the return line from the same tank using NFPA 13 code, but that was 6" ductile. Operating pressure will be 60psi, and there are 3 Mueller inline couplers from building to tank.
> Thanks,
> John


I would ask the foreman to show me the specs for the test and what method is to be used? He might not be smokin crack but it sure seems like he's nippin' on a flask. Never even tested gas or air lines at that pressure.


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## WC&T (Feb 22, 2010)

Usually you test domestic lines at 25-50psi over static pressure or at 115 psi whichever is greater. Even Fire line is only tested at 225 psi not 250. I wouldn't test anything over 120psi that is not restrained (rods, megalug,blocking or field lock gaskets). Make the QC show you in the specs that it has to be tested to 250 because i would bet that those compression fittings won't hold that high.


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## fireguy (Oct 29, 2006)

Anti-wingnut said:


> Well, if you do go to 250 psi, water test it, not air. I used to work at a ASME pressure vessel fabricator, and we had to test all our tanks. A failure with air is really dangerous, because of the compressibility of air. Because water is not (really) compressible, a failure does not result in shrapnel.
> 
> A pressure washer is the tool of choice to bring the pipe up to head.
> 
> That said, I would want someone to prove that it needs 250 psi


 
Your local fire sprinkler guy should be familiar with pressure testing, and he should have the proper tester, not a pressure washer.


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## Anti-wingnut (Mar 12, 2009)

The more I think about things, the more I realize that my suggestion may be a little unrealistic, as Fireguy pointed out. You will probably be dealing with a relatively small volume, and need to "sneak up on it".

That said, large gas powered pressure washers are the machine of choice for pressure testing ASME pressure vessels, unless a very large feed pump or similar is needed. We would replace the handle with NPT high pressure fittings, and pipe right into the vessel. Our vessels were large enough that we needed to run the machine up to 1/2 hour.

We had previously owned specialized test pump, but they broke down often. The use of pressure washers is common with companies certifying medium sized pressure vessels according our Hartford Steam Boiler inspector


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## dayexco (Mar 4, 2006)

i'd make him show me in the spec where it calls for a 250 psi test...if nothing is specified..i'd ask the local governing authority what their requirements are....we use a 3 HP 
$350 honda powered portable pressure washer for testing ALL the time, works slicker'n snot on a doorknob

for our longer mainline testing, "typical test here is 125 psi"....we have a 1500 gallon poly tank we put on a trailer, stick a 1 hp submersible pump like you'd use for a residential well....and tie that into a fire hydrant, fast, cheap


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## guyute65045 (Nov 23, 2006)

dayexco said:


> i'd make him show me in the spec where it calls for a 250 psi test...if nothing is specified..i'd ask the local governing authority what their requirements are


That's the problem, there is not a word on the plans or in the spec book about testing this line. I just want to make sure it doesn't leak before the slab gets poured over it. I like the gas pressure testers, they give great results.


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## Little (Jul 22, 2006)

thats absurd!! 250 pounds on a domestic line ha. Like everyone else has said that would be max psi on a fire line. I don't know what those compression fitting are capable of handling though.


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## cexcavation (Apr 17, 2008)

Around here, a test consists of holding actual service pressure overnight. I see no point in fatiguing the line beyond what it's actual usage will entail. I can understand the high test on fire lines, mainlines, etc. but a service line???? 

Realistically, a leak will show at a lower pressure, it simply won't be as "violent". 250psi seems like it would be excessive for something that is not "emergency" rated, etc. 

I typically sleeve all of my water line if it goes through concrete. In case of failure, you can just slide out the old and pull in the new.


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## Blas (Jan 29, 2008)

The guy is on crack period!!!! This is the most absurd thing I have ever heard of in my life. If you test it out at 250 psi you will most likely be tearing it out and starting over. We have never tested a line over 125 PSI for *6" main line*. I would check with your city inspector requirements and call this guy out on this test. Make him show you in the contract documents where it says a test at 250 PSI is required and if he finds it tell him to have that verified because it is a TYPO>>>>>>:thumbsup::thumbsup:


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## PipeGuy (Oct 8, 2004)

guyute65045 said:


> I have to test my 2" copper...at 250psi for 2 hours with no leakage? I have never tested copper at that pressure before, I would be hesitant to trust the....compression fitting. There is nothing mentioned in the spec book about testing.
> Anybody have experience with this pressure or is the guy just smokin crack?


I test copper all the [email protected] 125PSI for 2 hours - never 250 PSI. If a needle gauge is used then no leakage is allowed. If a recording gauge is used then the maximum amount of allowable leakage in gallons per hours = (the product of the square root of the average test pressure developed in the test segment in PSI and (the product of length of the copper in feet and its nominal diameter in inches)) divided by 133,200. As an example, 1000' of 2" copper tested for 2 hours at 125 PSI has an allowable leakage of not more than 43 ounces.When you're dealing with those kind of nominal leakage volumes you gotta be pretty careful to have a good means of measuring how much water you re-introduce over the test period.
I don't think the 250 PSI spec is a big deal provided all the joints are restrained - but it's definitely overkill. If it were me I'd be pushing for use of the AWWA recommended testing procedure as the standard for acceptance testing; its tied to the prevailing working pressure.


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## waldrop (Jan 3, 2010)

have done 200psi for two hours for years. but 250psi is a little crazy seeing that working psi is 60 ,so 3x60 =180 psi should be the test


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## The Coastal Craftsman (Jun 29, 2009)

We used to wet test at 10 bar which is about 150psi on almost all new builds 1/2"-2" lines mostly. I have had the tester upto 20 bar many times just to stress the system. I have had Speedfit fittings at 20 bar with no issues so a 2" copper line should have zero problem with 250psi but it is over kill.

This is what we used. a RP50


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## Kgmz (Feb 9, 2007)

What kind type of copper is this? 

Also drawn or annealed?

And are there any joints, and if so what were they soldered or brazed?

If soft soldered, a 2" soldered joint is only rated at 175 psi. 


Edit:

Just reread your post and saw the part about a compression fitting.

If this fitting will be underground it is not allowed around here. Any fittings underground have to be brazed or hard soldered as I call it. Also if the underground run is over 50' normal length for a roll of annealed or soft copper, then you have to use drawn or hard copper with brazed joints and end fittings.


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## The Coastal Craftsman (Jun 29, 2009)

I would guess type L or M. Even type M has taken 20 bar tests without issue for me and this is with soldered endfeed. Off course the system never gets to them pressure so you rarely have to worry about it. You also have to remember that like everything that has a rating they are normally rated way below what they can take. My truck says it rated to carry only 900lbs but i have had almost 2000lbs in there with zero issues.


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## dayexco (Mar 4, 2006)

BCConstruction said:


> We used to wet test at 10 bar which is about 150psi on almost all new builds 1/2"-2" lines mostly. I have had the tester upto 20 bar many times just to stress the system. I have had Speedfit fittings at 20 bar with no issues so a 2" copper line should have zero problem with 250psi but it is over kill.
> 
> This is what we used. a RP50


a new, clean grease gun works well on small diameter/short lines if it's full also. take the back cap off, hold vertical, fill with water/pump


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## Kgmz (Feb 9, 2007)

BCConstruction said:


> I would guess type L or M. Even type M has taken 20 bar tests without issue for me and this is with soldered endfeed. Off course the system never gets to them pressure so you rarely have to worry about it. You also have to remember that like everything that has a rating they are normally rated way below what they can take. My truck says it rated to carry only 900lbs but i have had almost 2000lbs in there with zero issues.


 
My post was for the OP.

If the pipe you have says is rated for 900 lbs then is must be type L or above. Actual burst pressure for all types 1 1/2" and smaller are above 2000 lbs. But you have to derate on how any jioints/fittings are soldered or brazed.

Many years ago I learned how to silbraze copper from my dad when I was in high school and then installed high pressure and refrigeration lnes for a couple of years after, and still do for any of our projects that need them. Nothing like getting 3" or larger hard copper up to brazing temp with 2 torches and then pressure testing the system with nitrogen after.

For some good info on copper pipe, go to copper.org and download the copper tube handbook.

http://www.copper.org/publications/pub_list/pdf/copper_tube_handbook.pdf


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## guyute65045 (Nov 23, 2006)

OMFG! 
This $h!tshow actually pushed me today over this water test what a 
tool. 

I used my pressure washer and to quote Day, "slicker then snot on a doorknob.


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## The Coastal Craftsman (Jun 29, 2009)

How do you go about doing it with a pressure washer? Never seen it done like this before. How to you regulate the pressure. Def wouldnt want to connect mine to a copper pipe at 3000psi!


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