How to test 25mm mdpe pipe

[Canal Navvy]

that set up needs a tap between the compressor line and the plumbing ... or a schrader valve and disconnect once pressurised ... will leak back through the compressor Giles

If it held for an hour it held for an hour, no reason to look for any leaks in either the pipework or the test kit.

On Vinpetrols problem he needs to be sure that his pipe is not leaking outside of what is normally acceptable. If he pressurised it, isolated it and came back in an hour and the pressure was gone it could look like a problem when no problem exists. If the pipe is totally filled with water the compressible part is so small that it tells you nothing.
Ideally he needs to isolate his part, take it up to a test pressure from one end using a pressure vessel and a tee with a tap and a pressure gauge. Pump it up to say 4 bar, give it a while for it to settle and then note the pressure on the gauge, leave it for an hour and check the pressure. If it is the same it is a definite pass, if not stage two is to pump it back up to the original pressure and then using the tap run the water out into a measuring jug until it matches the lower pressure and you have the leakage rate

 

[Giles]

that set up needs a tap between the compressor line and the plumbing ... or a schrader valve and disconnect once pressurised ... will leak back through the compressor Giles

The test clock is 1 way you have to unscrew the valve fitting out of it to release the pressure

Has a Schrader valve in it

 

[pettsy]

I was always taught to test 1.5 x working pressure

 

[DaveDCB]

The test clock is 1 way you have to unscrew the valve fitting out of it to release the pressure

Has a Schrader valve in it

That’s neat, the one I have just goes on the end of a standard tap 3/4” .
Only really use it to check preassure before specifying type of heating system.

 

[Vinpetrol]

If it held for an hour it held for an hour, no reason to look for any leaks in either the pipework or the test kit.

On Vinpetrols problem he needs to be sure that his pipe is not leaking outside of what is normally acceptable. If he pressurised it, isolated it and came back in an hour and the pressure was gone it could look like a problem when no problem exists. If the pipe is totally filled with water the compressible part is so small that it tells you nothing.
Ideally he needs to isolate his part, take it up to a test pressure from one end using a pressure vessel and a tee with a tap and a pressure gauge. Pump it up to say 4 bar, give it a while for it to settle and then note the pressure on the gauge, leave it for an hour and check the pressure. If it is the same it is a definite pass, if not stage two is to pump it back up to the original pressure and then using the tap run the water out into a measuring jug until it matches the lower pressure and you have the leakage rate

If there is a leak it should be apparent fairly quickly as the pump is cutting in and out all the time that the additional run of pipe is live . I think a test will tell me very quickly if I have a leak . I’m going to the job tomorrow and hope to rectify it . I’m taking the mini digger as well so if it fails the test I can look for the leak .

 

[Canal Navvy]

If there is a leak it should be apparent fairly quickly as the pump is cutting in and out all the time that the additional run of pipe is live . I think a test will tell me very quickly if I have a leak . I’m going to the job tomorrow and hope to rectify it . I’m taking the mini digger as well so if it fails the test I can look for the leak .

Be surprised if your work is all of the problem, even a missed insert/liner doesn't leak that badly.
The need for a booster pump on an incoming main would have me wondering if there are any low pressure ball valves in the system that are now not liking the increased pressure and the spur you are dealing with is just causing resonance that is making the pump cycle.

 

[V8Druid]

The test clock is 1 way you have to unscrew the valve fitting out of it to release the pressure

Has a Schrader valve in it

can see it in the original pic, now you say and I have the pic of the valve unit to see too

 

[Vinpetrol]

Be surprised if your work is all of the problem, even a missed insert/liner doesn't leak that badly.
The need for a booster pump on an incoming main would have me wondering if there are any low pressure ball valves in the system that are now not liking the increased pressure and the spur you are dealing with is just causing resonance that is making the pump cycle.

That’s what I’m wondering . This is one of the last of 10 plots and I know of 2 others with pumps

 

[Gecko]

~ if there are any low pressure ball valves in the system that are now not liking the increased pressure

Interesting point. I've actually got a float valve that would do that is it weren't for the pressure tank.
It's the header tank for the hot water tank - it squirts for half a second, then the incoming water gives the float extra buoyancy causing it to shut off.
If there were no pressure tank, then the pump would cycle with it.
If I simply turn down the control valve, the flow rate will decrease and the oscillation will stop (care factor is a bit lacking though)

 

[DaveDCB]

Always easier to blame the Groundworker / digger driver isn’t it?

 

[Steve]

Always easier to blame the Groundworker / digger driver isn’t it?

That’s what usually happens & it should be chargeable when ground worker/digger driver proves otherwise.

 

[Giles]

How did the test go?

 

[Vinpetrol]

How did the test go?

We put the test on the outside tap that was teed into the run and it tested fine . Then we realised that the tap has a non return valve so we were only testing the tap. We gouged out the valve of an old tap and fitted it on and tested again and still the test was good . I had installed a boundary box for the outside tap though so it could be shut down in winter and I realised that this also had a non return valve so I was only testing from the boundary box .
I then exposed the boundary box as I know that they can be a bit awkward to push the pipes into but all was fine and dry .
We then switched the testing tap to a point in the garage which we knew wasn’t covered by a non return valve. It was dropping slowly.
We then exposed the tee that split the supply to the outside tap from the garage . It was really wet in the ground so we suspected this was the issue . The only thing was , when we turned the water on It didn’t leak !
We took the tee apart and fitted the outside tap to the supply from the house and this tested fine .
When we inspected the tee one of the rubbers that sealed it was actually cut right through. We couldn’t figure out though why it didn’t leak when we exposed it .
We replaced the tee with a new fitting and backfilled and tidied up the drive . All was good while we were there .
I checked in with the clients over the weekend and the pressure was still fine .
I can only assume that the tee was raxed under pressure from the backfill enough to let it leak but when we exposed it this pressure was relieved and it managed to hold .
Either way the system seems to be fine now and clients are happy .

 

[Stroppymonkey]

I’m surprised to read about a pump on the mains pipe? Under water regs you are only allowed to fit crappy little 12lpm inline boost pumps to mains pipework. Maybe that’s what OP has? If it’s a conventional pump set with vessel connected direct to supply then it a contravention

 

[Stroppymonkey]

We put the test on the outside tap that was teed into the run and it tested fine . Then we realised that the tap has a non return valve so we were only testing the tap. We gouged out the valve of an old tap and fitted it on and tested again and still the test was good . I had installed a boundary box for the outside tap though so it could be shut down in winter and I realised that this also had a non return valve so I was only testing from the boundary box .
I then exposed the boundary box as I know that they can be a bit awkward to push the pipes into but all was fine and dry .
We then switched the testing tap to a point in the garage which we knew wasn’t covered by a non return valve. It was dropping slowly.
We then exposed the tee that split the supply to the outside tap from the garage . It was really wet in the ground so we suspected this was the issue . The only thing was , when we turned the water on It didn’t leak !
We took the tee apart and fitted the outside tap to the supply from the house and this tested fine .
When we inspected the tee one of the rubbers that sealed it was actually cut right through. We couldn’t figure out though why it didn’t leak when we exposed it .
We replaced the tee with a new fitting and backfilled and tidied up the drive . All was good while we were there .
I checked in with the clients over the weekend and the pressure was still fine .
I can only assume that the tee was raxed under pressure from the backfill enough to let it leak but when we exposed it this pressure was relieved and it managed to hold .
Either way the system seems to be fine now and clients are happy .

When fitting HU Bib taps always choose ones with out DCV (double check valve) (or remove them) and fit correct check valve and isolation indoors or in a chamber. First frost you get and the tap will cease working as the little spring loaded valves push out and jam up

 

[Bucket on wheels]

In Norway, a frost-proof outdoor tap is a requirement

 

[V8Druid]

In Norway, a frost-proof outdoor tap is a requirement

View attachment 50211

have seen those installed in some of the youtube vid.s I watch of 'off gridders' in the states ... looks a clever set up with the actual valve indoors

 

[DaveDCB]

have seen those installed in some of the youtube vid.s I watch of 'off gridders' in the states ... looks a clever set up with the actual valve indoors

I always fit them back to the wall with a iso valve inside, just got to remember to turn it off and open up the outside tap lol

 

[pettsy]

I do outside taps with just a female iron so no exposed pipework.

 

[Vinpetrol]

I’m surprised to read about a pump on the mains pipe? Under water regs you are only allowed to fit crappy little 12lpm inline boost pumps to mains pipework. Maybe that’s what OP has? If it’s a conventional pump set with vessel connected direct to supply then it a contravention

It’s a tank approx 500l with a pump in it. I didn’t do the install the plumbers did it so I can’t comment on the legality off it but all the houses in the wee development have them as mains water pressure is a bit low