Old Fittings Fight Back

[btibuzz]

I am attempting to bring hot water to a bath tap via the tee in the attached pic.

I've got it working sort of using a push-fit reducer, but although it's on straight it appears to be weeping a bit. I think the cause may be the pipe its going onto.

The issue is that whilst it is old, I don't think it's imperial (3/4") I think it's 22mm but an old 22mm (although you can't see it in the pic it actually says 22 on the compression nuts).

I was able to put a new piece of 22mm pipe, with a new olive on the vertical tee and use the new 22mm compression nut to do it up (threads matched etc).

However it never did up enough to compress the olive and create a seal. (pipe was still loose in the fitting)

Comparing it with the old piece of pipe - it appears the old olive is bigger, also the pipe itself appears a little smaller (new 22mm pipe will not go into the old compression nut)

Questions...

1) Is there an old 22mm that is incompatible with new 22mm or am I just missing something?

The continuation of the tee is now dead so I could replace with an elbow. However given that the old pipe appears to be slightly smaller diameter than new 22mm pipe...

2) would a new 22m end feed fitting work?
3) would a new 22mm compression fitting deal with a the smaller pipe better?
4) would PTFE/Loctite xx be of any use to me here to bulk up the pipe/olive to help seal?

5) Am I going mad and actually looking at 3/4" pipe and there's a simple imperial-metric connector that would do the job?

Once in new fittings, I think I know what I'm doing - any help greatly appreciated.

Cheers

Paul

 

[stevew451]

go to a plumbing outlet ask for an 3/4 imperial olive for 22mm pipe and try that

 

[Bernie2]

Yes as Steve says, often it was just a case of swapping the ring in a 22mm fitting for a 3/4" imperial for it too work. Must admit I never liked it much, the imperial pipe swam around a bit loose and sometimes you could see the imperial ring nearly coming out the back of a 22mm backnut.

I preferred a soldered 22 x 3/4 coupler and change over to 22mm. But as you say its not always possible to do.

 

[btibuzz]

Well after a trip to plumb centre and toolstation I've now got..

3/4" - 22mm end fit couplers
22mm compression coupler and a pack of 3/4" olives
22mm elbows
15mm elbows
22mm pipe
15mm pipe.

Something's bound to fit! Wish me luck.

Paul

 

[danielp]

if you use a copper olive that works , never really has a problem just need to tighten more

 

[REDSAW]

the pipe could also be niether 3/4 or 22mm,
it could be gas thread / 20 thread, in which case it will need a brass conversion socket.

 

[Mbear]

I've had this issue with joining old steel pipe to new copper. My fix at the time was to wrap the smaller pipe with ptfe so the olive would sit over the ptfe if you get the idea then put the nut and olive over the ptfe on the smaller pipe and proceed to wrap the olive with loads and loads (don't be shy with the tape) of 'gas' ptfe tape. The gas tape is obviously thicker and more suited to this than the water tape. Proceeded to tighten(give it some beans as my old tradesman used to say lol) it as much as possible and it sealed no probs. I defo believe the gas tape was the key to a good seal on it though.

Hope thats helpful

best of luck

 

[justlead1]

Hi. You would not be a plumber if you did not pull a few strokes when time restraints apply , but using nut and olives to connect copper to iron is not a good practice under normal conditions. Or perhaps i am reading it wrong?

 

[btibuzz]

Well what worked in the end was...

left old 3/4" tee in situ
used New 3/4" olive in one end of 22mm compression coupler and fitted to the vertical 3/4" pipe.

Fitted male 22mm end of 22mm-15mm end fit reducer to the other side of the 22mm compression coupler.

Soldered in small length of 15mm pipe to the female 15mm end of the reducer
push fit flexible tap tail to 15mm pipe

It might not be the prettiest job in the world but I think the individual connections are 'as designed', it's not bodged up with tape and it ain't leaking (at the moment).

(Have advised my mate not to put back the bath panel for a week or so to keep an eye out for leaks)

Thanks all for the advice.

Paul