Plumbing help. Plastic pipe and compression fittings

Simon

Simon

Simon

Caporegime
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Hi.

I've had a nightmare just now. I have replumbed my bath with 22mm speedfit pipe and compression fittings.

I have turned the water on and most of fittings are leaking where I used plastic. The copper fittings are fine and so are the speedfits in the system.

I did the fittings up pretty tight but was slightly wary of breaking the inserts.

So what have I done wrong ? Even though they were all tight some would spin and some came off with a yank. On inspection the olives have bitten in to the plastic a bit. The olives are brass rather than copper.

PTFE time ? :( or just tighten them up even more ?
 
You are using pipe inserts in the plastic pipe, & the fittings are normally grip & seal.

Also you should use copper olives NOT brass as it's to hard to compress properly, the connection should not need more than 2 full turns after the olive has gripped the pipe.
 
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Thanks.

Plastic is cut square and using the standard inserts without o ring as recommended. Pipe is 22mm speed fit. I have 2 90 deg elbows for the bath tap manifold and also the manifold 22mm to 1/2 inch fitting all having plastic pipes.

The T pieces off the old bath circuit ( now feeding sink are a mix of copper and plastic).

Looks like brass olives and maybe some JetBlue sealant are my friend ?
 
Yeh they came with the fittings :( I was careful to avoid over tightening so hopefully I can just swap brass for copper ? Is ptfe worth adding?

No water in my house :( fail
 
Are you using copper compression fitting to speedfit, I always found it easier to use speedfit straight joiner or reducing straight to join plastic & copper.

Link: http://www.jgspeedfit.com/Home/Tech...al-Downloads/118/DIY-Installation-Manual.aspx

Don't use much plastic myself, I'm old school copper pipe & solder user.:eek:

EDIT: Shouldn't need ptfe.

Yes, you can swap brass olives for copper olives.

Brass olives are for copper pipe, use them in plastic pipe & you will never get a water tight seal.
 
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Seldom use ptfe tape, I tend to use Fernox Water Hawk jointing compound if needed on copper compression fittings.
One benefit it's approved for drinking water pipework as well.
 
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Thanks for the help, I lifted the tank stop cocks and turned on the mains only to at least have some water.

I am using copper compressions to speedfit, mainly for the smaller size and what I thought, more robust fitting as they will be difficult to get to.

Will be off to get some copper olives and jointing compound later.
 
Before, due to installign marmox boards I would have to tweak the piping and also its only 15mm at moment. 22mm runs to where bath was.

37E21057-1EF6-4CDD-B09D-17A854149D2A-711-0000006DBAE4E147_zps5f13563b.jpg


I replumbed with 22mm and chased into wall. I used compression thinking they were more robust - and benefit from being more compact

AA8B5F0A-30E1-45B6-9654-C52D063DF2DC-711-0000006D988755F4_zpsb611f8ea.jpg
 
Simon said:
Before, due to installign marmox boards I would have to tweak the piping and also its only 15mm at moment. 22mm runs to where bath was.

37E21057-1EF6-4CDD-B09D-17A854149D2A-711-0000006DBAE4E147_zps5f13563b.jpg
Click to expand...

Wow! what a mess of copper pipework.

Ah,I see what you done now, using copper compression fitting to join two plastic pipes.:(
You install Speedfit correctly you will not have a problem, work I did 10 years ago with HepO2 is still solid, shower I got here was done 3 years ago with Speedfit is still perfect.

Better off buying two speedfit Eblows, two speedfit tap connectors I think, if everything is leaking & you can't salvage it with copper olives.

When I've been faced with similar situation, I always make the chase cutout slightly deeper to accommodate the fitting, easier than mixing & matching.
 
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Yeah the airing cupboard is at top of the pic and boiler is underneath, also the piping to a radiator goes that way too.

How I left it last night:
8D8366F4-DED8-495C-AE45-9FF2ECF4C9C8-971-00000093A1F512D8_zpsbae5cc0d.jpg
 
I can see that now, lets see how copper olives go. I still need to fit into the tap manifold with some sort of fitting as I don't really want the speed fittings in the wall.

I though having plastic pipes does away with the need for earth bonding? The metal taps etc are now isolated from earth.

I guess if it all goes wrong I can go for speed fits and new pipe - the current stuff will be affected by the olive, although i guess it does go deeper into the speed fits than the compressions.

I honestly thought compressions would be better, easier to fit and more durable :(
 
Simon said:
I can see that now, lets see how copper olives go. I still need to fit into the tap manifold with some sort of fitting as I don't really want the speed fittings in the wall.

I though having plastic pipes does away with the need for earth bonding? The metal taps etc are now isolated from earth.
Click to expand...

Looking at your pic, you have used a plastic tee from copper to plastic, back to copper, you should install a bonding conductor across the fitting to maintain the conductivity.
 
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