leaking joints or not??

[jb1468]

Hi Folks,

I need reassurance and/or guidance. Completing several plumbing jobs at the moment and I have exposed (not replaced floor boards etc) copper pipes and joints all over the house. Reluctant to cover over/complete second fixes until I'm sure that they are water tight as It will cost a lot of money to rip up floors/tiles etc if i discover too late they are not.

Ok - so I am testing by attaching/connecting temporarily various devices. I have run them for 10 - 30 mins and the problem is this. I have inspected carefully and altho there is definitely no obvious leeks (i.e signs of water or drips from any place) when I run my fingers gently over the joints my fingers/hands at times are a little damp. By damp I mean the very slightest signs of wetness.

Is this normal?...does it take time to settle? or is it likely to develop into a more obvious leak?

I would appreciate any help on this as I need to get on with the rest of the job.

Many thanks

 

[Goldspoon]

Wipe your joint with tissue paper so it is 100% dry everywhere when you touch it. If you touch it later and you get any wetness at all then I would, without doubt, see that as a problem that can get worse. It is either 100% watertight or not satisfactory in my opinion. One thing I have learned with plumbing is that if there is any doubt, any doubt whatsoever (or any tiny smear of water on a finger)... then that's your warning.

The above is more usually relevant to compression joints as I've never had a soldered joint weep - have had water hissing out or it's fine... no in between for me.

If compression joint has wetness then tighten it a little and test again. If already at max tightness then undo nut and add some PTFE tape to olive and then retighten.

 

[kevplumb]

did you clean the flux off properly

 

[mogget]

It's possible to get a little condensation if the pipe is filled with very cold water, in this instance the pipe and joint would be affected equally.

Quite often when I check a joint, it feels slightly damp but actually is just cold.
If I need to check I fill the pipe, wait a little while, give the joint a wipe with kitchen roll, and check again a few minutes later.

edit: Just noticed that goldspoon uses a similar method, that'll teach me to reply without reading through

 

[Goldspoon]

did you clean the flux off properly

Are you thinking that the OP is mistaking flux for water?

 

[jb1468]

did you clean the flux off properly

Are you thinking that the OP is mistaking flux for water?

thanks, no I'm not mistaking water for flux....but i will try advice above to see if condensation thanks

 

[Master of None]

Are you saying you are testing by running mains water for 20 - 30 mins to an open tap or other outlet? If so it will probably be condensation.
You should really test the system with a gauge with all taps/outlets closed and vented.

I am just a diyer but i thought the others may have misunderstood your testing procedure.

 

[Goldspoon]

Are you saying you are testing by running mains water for 20 - 30 mins to an open tap or other outlet? If so it will probably be condensation.
You should really test the system with a gauge with all taps/outlets closed and vented.

I am just a diyer but i thought the others may have misunderstood your testing procedure.

No misunderstanding here.

 

[swidders]

If you're not sure, drain it down and get an air pressure guage. Has the advantage of not getting anything wet, especially any joints that you may need to resolder possibly without having to dismantle.

 

[Softus]

If you're not sure, drain it down and get an air pressure guage.

No.

No no no.

No no no no no no no no no no no no no.

Has the advantage of not getting anything wet

Has the disadvantage of embedding shrapnel in your brain and nethers if something goes wrong.

Never, ever, ever, EVER, test with compressed air.

 

[Slugbabydotcom]

So you won't be needing one of THESE then.
I have seen the truck force safety video regarding the safe inflation of tyres. They are at about 120 psi and can cause a lot of damage when they go. I think we all heard about the guy who got splattered on a ceiling when a tractor tyre exploded so lets try to get this into persperpective.
If it wasn't 'safe' then screwfix wouldn't be selling those kits. You will note that the pressure they recommend is 60 psi. I am sure the normal protocol for testing anything is 1.5 times the normal working pressure. A quick calc in my head says that roughly 65psi is equivalent to 4.5 bar allowing for the fact that the PRV should kick in at 3 bar then I would be happy with 60 psi.
Now when a wagon tyre blows the escaping air is all in one place which can propel the wheel in a violent manner. The 'lads' told me about a recent blast where a wheel jumped into and totally trashed the inside of a new van as it blew.
In a system I suspect that a rupture would occur on the seam of a pipe or a fitting could fly off. Most fittings are in the line of a pipe so if one joint breaks then the fitting is still attached to the other. Remember that the volume of air in a system is likely to be much lower than a large tyre in the majority of cases
Personally I would say that the dry tester is fine for occasional or one off use and more suited to your situation, but dont forget what is now known as risk assessment but used to be called common sense.

 

[Softus]

...lets try to get this into persperpective.
If it wasn't 'safe' then screwfix wouldn't be selling those kits.

Oh that's all OK then.

So you'll be buying your kids one of these next Christmas:

Click here to order online:

http://www.screwfix.com/prods/85530...s/Chainsaws/Makita-45cm-3-5hp-Petrol-Chainsaw

A quick calc in my head...roughly ...I suspect...likely to be...in the majority of cases...Personally I would say...

It's so lucky that safety is an exact science.

 

[jb1468]

interesting debate.......im sure i will stick with the old tissue paper........i get paranoid enough on working with water. by the way I am not doing the work....a plumber is....just i like to be sure before i start tiling etc

thanks all