Help... Compression joint... Tiny bit leaky...

[John Rumm]

In which case, undo, thin wipe of LS-X over the olive and do it up again. ;-)

[Tim Watts]

No. I managed to take the old pipe off with just a towel :) There's only

2.5m of pipe above that, then it goes down again.

[Tim Watts]

Water...

OK - I will try.

[Tim Watts]

I have some Hawk White (Potable) - run out of non dead LS-X

[Tim Watts]

OK - undid the nut 1/6 turn and did it back up, slightly harder.

This is the extent of the weep after exactly 10 minutes:

What does the jury reckon - leave to self heal with mineral deposits?

I was thinking of some Hawk but I'll obviously have to pull the joint apart - sleeping dogs and all...

[Tim Watts]

Just under 30 minutes:

About a raindrop's worth...

[Jeremy Nicoll - news posts]

So when you did it up "slightly harder" what stopped you from doing it up "slightly more than slightly harder"?

Presumably each time you tighten it (more) you see less water... Am I being naive in thinking you just keep tightening it until the leaks stop?

[Tim Watts]

There seems to come a point where the resistance goes exponential rather than just being "a little harder".

It is possible to distort the olive - and it was getting hard enough that my Bahco adjustable was reaching it's limit where it's liable to slip the corners of the nut. This damn fitting of course does not match my 22mm open ring spanner!

Anyway, I said sod it and disassembled it with the aid of a big towel.

(Andy) I admit a draincock might have been helpful, but it was not too bad - 3 pints or so.

I have applied a smear of Hawk compound[1] around the olive and 1/2cm down the pipe - which looked prefect as did the valve seat, and bolted it back up.

I guess there must have just been a tiny nick in the seat or a sratch on the pipe or something.

It had bloody well better not leak now!!!

[1] OK LS-X might be a little kinder to the poor bugger who has to undo this in the future (hopefully not me) - but as I mentioned, my LS-X is dead and I happen to have fresh Hawk :) I was pretty sparing so hopefully it should come apart again. Only the top joint so I guess they can always change the valve, which is probably why they would be taking it apart anyway!

[Tim Watts]

****! I *think* I have finally managed to shut the bugger up...

Just.

Had to give it 1/12 of a turn which is all my spanners will stand.

At least now, after 15-20 mins I can not feel any wet around the thread.

It's always the most awkward one (awkward because I need to KNOW this is dry in a week when it gets a cupboard shoved in front).

On the plus side, all the other joints seem to be well behaved... Which I suppose isn't too bad 24 odd compression joints and only 2 gave me jip.

Plumbing - on my hate list...

[0845.86.86.888]

Done that myself a few times. :)

I've also had a detectable air hiss on pressurising pipes to find that water being "thicker" doesn't get through spaces that air can.

Testing with gas leak fluid is a bit extreme for plain old water pipes though.

:)

[John Rumm]

Oh yes... last time I had a compression that would not seal:

[Tim Watts]

I remember that...

At least mine is accessible - for the moment!

The trouble with DIY is the more I do, the less I feel I know...

I've done stuff to rescue concrete floors that no builder would ever attempt. But I still get caught out by silly shit :(

Remember I said "what's this blue-green deposit on this here main water valve thread?" "Maybe it was plaster being chucked about?

I wonder in retrospect if my original joints had a bit of trouble and weeped for a while... I did not care back then - I just gave it a cursory look.

[Tim Watts]

An hour later - damp threads, no drip.

I guess I'm just going to have to leave this to seal itself...

I think taking it apart *again* to try say PTFE tape is just going to make it worse...

[Bill]

That reminds me of a flood in my parents lounge ceiling in about 1965. We had just, the week before had central heating fitted. One evening the lights started to flicker, not uncommon out in the wilds in those days. Then the lights finally went out and while we were checking the fuse, a large ceramic one in a very large metal box in the most inaccessible corner of the kitchen, part of the lounge ceiling collapsed. It was rather flimsy plaster and lath the had seen better days. It didn't help that a year or so before I had set fire to the lounge and the ceiling hadn't been quite the same since.

Any way, the problem was tracked down to a plumber having slid a length of 1/2" copper over a bit of lead covered wiring that fed the light and worn through the lead, the inner rubber had finally given way and merrily arced a hole through the pipe.

A few morals from this.

Use a better plumber. MCBs are worth the while. RCDs/RCBOs even more so. Fit smoke detectors. Don't let 5 year olds play with the open coal fire.

Luckily most of these problems would not occur these days.

[John Rumm]

If your water is anything like as hard as ours, then it won't take long.

Could it be you had a dodgy batch of fittings?

Unless there is something particularly odd with the technique, I would expect failures on compression joints to be very rare on new pipe, even if used without sealants etc.

[John Rumm]

So was mine - slowly!

That might actually be the nub of the problem - over thinking some of these jobs. If you stress over them, it quite possibly disrupts the job. Bit like my dripping fitting - perhaps the extra pressure of "its really important this does not leak" because of its location and the difficulty of getting to it etc, causes the subconscious to do it up just a bit tighter than normal "to be sure" and snatch defeat from the jaws of victory?

[Tim Watts]

This is a 6 year old Peglar 22mm lever valve. It's been OK (unless it weeped the first time and I didn't notice).

I was super careful with this one - fresh bit of pipe, checked for scratches, new olive etc.

Started with 1/2 turn then 1/12 increments so as to not over tighten. Now at 3/4 turn.

Well, overnight (7 hours) it did not actually run any drips down the side, but the threads were wet - about 3 drops of water.

Hmm - still not happy given it's going to be harder to access than many other joints. If I went back 6 years, I'd have bought the main in 18" to the right under the house, but I did not know the kitchen layout then.

Know what - I'm out of time and ideas - I'll admit defeat call one of the CH plumbers who are giving me quotes...

[Tricky Dicky]

Tim I would not be scared of giving the fitting a bit more tightening but w ould use spanners rather than pliers unless you have used Konex types where you do not have much choice. I have recently repositioned a lot of pipe wo rk to facilitate insulating this involved a lot of cutting out sections and rejoining the same pipes. Due to the difficulty of getting every bit of wa ter out I was limited how much I could solder so had to use a number of com pression joints. I never use the likes of Boss White except in desperation and I have never had a joint fail as a result of overtightening. On this la st job only two joints showed any leaks, one an existing joint that had sla ckened with all the raunching of the pipe work and was soon sorted with a r e-tighten. The only other problem was an isolating valve that kept weeping at one end and needed a bit more than usual tightening but even that eventu ally got sorted with a bit more tightening. You do get some rogue joints th at seem to need a bit more effort and sometimes replacing them is less stre ssful than trying to make it happen. Having put in 2 CH systems and re-plum bed one house entirely I have never had a compression joint that could not be sealed usually by further tightening or the use of a sealant in desperat ion. Neither have I had a joint fail as a result of over-tightening.

Richard

[stuart noble]

Now that is interesting, particularly the last sentence, which contradicts everything I've ever read in DIY books. I don't think it's any coincidence that plumbers seem to be the most unreliable of all the trades. If every job has a snag, the day gets longer and longer

[Tim Watts]

True - I wish I had spanners for the "other" type of nut. I have a lovely 12" long open ring that fits most 15 and 22, but not Peglar!

We are firmly in the desperation stage now :(

Odd you should say that... I was going to swap the whole valve out as it's an 8 quid part and I'd be leaving a 6 year younger valve in.

However, Mr Sod made sure the street stop c*ck would not shut off properly. That's a new-ish ( Having put in 2 CH systems and re-plumbed one house entirely

Thank you for the vote of confidence Richard.

I tell you, fixing this bloody house is really getting on my nerves now. In hindsight, it was too big a job. But we are nearing the end. Just some electrics to do properly, a shower room the dormer upstairs...

I've called in one of the plumbers who's doing me a CH quote - he's popping around tomorrow morning. At least he has a little incentive and whilst I'm not as good at stuff as lots of people here, I do know when to give up...

Oddly enough I have a tiny drip on another valve round the back, but that does not bother me because it's not getting blocked in and I have not even tried to do that up yet.