PTFE round olives

[Softus]

The thread? Of a compression fitting? Why?

in a compression fitting seems to me there's 3 lines of defence....

Stop right there - you're wrong.

The olive forms a seal between the fitting and the pipe. That's it. No other sealing opportunities exist.

...the seal between the top of the olive and the female fitting. If that happens to fail there's 2 other places where water could weep out, where the bottom of the olive meets the nut and then the thread.

No. If the olive doesn't seal the fitting to the pipe, then water will comes out, no matter where you put sealant or tape.

To all those who advocate using nothing and are in the 'if the joint is done properly you don't need anything' brigade then I assume you've never had a weeping joint? and every time it's perfect?

No, they all use jointing compound.

When I do a fitting I like to make sure it never leaks, EVER, especially if it's being boxed in and hard to get at.

You box in compressions fittings?

It takes seconds to wrap around some PTFE so the argument about wasting time doesn't cut it.

It does when you do thousands of them.

 

[markwm]

No, they all use jointing compound.

NO, they don't!! As some have already said they don't use anything.

You box in compressions fittings?

Hard not to when installing a concealed shower, for example.

 

[swidders]

markwm

you seem to have made your mind up to carry on doing what you are doing regardless of what others have said.

 

[KeithM]

Reading the manufactures instructions might shut us all up about this one!

 

[bengasman]

in a compression fitting seems to me there's 3 lines of defence.

like i said before, lack of skill or lack of training.

a compression fitting has one seal; between the olive and the seat.
you clearly have no idea how things work, nor how they should be applied.
that means you have, a justified, lack of confidence in what you are doing.

it is not so much that it is particularly bad or risky, it is simply a display of ignorance. but if it makes you happy, stick teflon tape above the olive, around it, under it, on the thread and wrap a few turns around the pipe for good measure.

 

[Softus]

No, they all use jointing compound.

NO, they don't!!

Yes, they do.

As some have already said they don't use anything.

Please show me one single poster on this topic who has said that they use nothing.

You box in compressions fittings?

Hard not to when installing a concealed shower, for example.

I've never had to, and it's very easy not to.

 

[Norcon]

Agree with markwm.
You can get a weep through the threads if the contact face between the inner bevel is damaged or just through the surfaces not mating properly.
ptfe will prevent this . Belt and braces approach and I would highly recommend it when fitting concealed cisterns or other compression joints in inaccessible places especially if you are not pressure testing.
Most manufacturers recommend a light smearing of lubricant as do the UK copper board.
On plastic the UK copper board recommend PTFE, fibre washers or rubber O rings as oil based lubricants or sealing compounds may react with the plastic compound.
Have just fitted 4 CC's in a property encased in solid stone. Will cost about £200 per cistern to fix a failure.

 

[ChrisR]

delete

 

[Norcon]

 

[roguetrader]

for added piece of mind i generally wrap ptfe round my head like a turban, far more useful than on a compression fitting.