Author Topic: Push-fit Plumbing Fitting Innards  (Read 376 times)

Push-fit Plumbing Fitting Innards
« on: February 07, 2019, 06:28:43 pm »
This is for an Aqualisa shower, the body of which has elbows with push-fit connections to 15mm pipework.  Working out the installation of the pipework meant I needed to trial fit the shower body without its inner components, but now I need to check the assembly order and orientation f the three inner components.  Aqualisa are not being very helpful, referring me to the installation manual, which I already have and which does not give this information, and no exploded diagrams..

There's a metal ring with teeth, which I think must point inwards; there's a grey ring with a lip (not sure which way round this goes), and a rubber ring
Is there a standard orientation of these components for any push-fit connection?  The plastic elbows have outer rings to tighten, though, which other push-fit components I've used don't have.

Shimano-style exploded diagrams would be so easy!  Why don't they supply them? Grr..

Feanor

  • It's mostly downhill from here.
Re: Push-fit Plumbing Fitting Innards
« Reply #1 on: February 07, 2019, 06:55:58 pm »
Sounds like you have dismantled the actual pushfit coupling, without noting how it came apart.

Don't do that.

Pushfit couplings come in several flavours form different manufacturers.
Eg Speedfit and Hep2O.
They are all slightly different.
Some are demountable ( ie you can use a tool to release the pipe from it ) , and some are not.

A picture of the bits would help.

Yes, the ring with teeth points inwards, so it allows the pipe to be pushed in easily, but digs into it to prevent it pulling back out. Like a ratchet.
The rubber ring is the o-ring, then main sealing part.
It should be obvious where that goes.
The grey ring may be a de-mounting collar, which can be used to slide down and disengage the teeth on the metal ring, but I'm not sure.
There will be a threaded collar to hold the whole thing together.



Re: Push-fit Plumbing Fitting Innards
« Reply #2 on: February 07, 2019, 08:07:29 pm »
Thanks, Feanor.

I feel suitably humbled. :-[

When I'm back where the bits are, I'll take a picture.

The little grey ring is part of the assembly, and of course there's a threaded collar to hold the whole thing together.

Re: Push-fit Plumbing Fitting Innards
« Reply #3 on: February 07, 2019, 09:52:01 pm »
Order of rings from open end of pipe is toothed ring (teeth  pointing towards the open end of the pipe) plastic ring (withe the lip pointing towards the end of the pipe and sitting inside the metal ring) then the o ring then the cap.

So if you are re assembiling the fitting put the rings in the open end of the fitting in the above order (metal, plastic, o ring) then put on the cap.  Then insert the pipe.

Re: Push-fit Plumbing Fitting Innards
« Reply #4 on: February 08, 2019, 06:32:50 am »
 push-fit designs do vary a bit. This is one



cheers

Re: Push-fit Plumbing Fitting Innards
« Reply #5 on: February 08, 2019, 09:39:42 am »
Agreed, but Speedfit doesn't have a loose metal toothed ring and the teeth in the plastic gripping part don't act until the pipe is pulled away from the fitting (or oushed by the water pressure).  The loose metal gripper has to be in board of the o ring as it can score the pipe on insertion which doesn't play nicely with an o ring seal.

Re: Push-fit Plumbing Fitting Innards
« Reply #6 on: February 08, 2019, 10:04:50 am »
I would also just point out that some of these do not work after being used once/disassembled.  you may want to be very careful the first time you turn the water on.  personally I would never re-use a pushfit connection but I am not a plumber and professional advice may differ.

Re: Push-fit Plumbing Fitting Innards
« Reply #7 on: February 08, 2019, 10:26:32 am »
You must use the insert in the end of the pipe.

This is not usually supplied with the fitting. It just pushes into the pipe and gives it extra rigidity (also ensures that very thin metal pipe is properly round). Not using these inserts is the main cause of push fittings weeping.
<i>Marmite slave</i>

Re: Push-fit Plumbing Fitting Innards
« Reply #8 on: February 08, 2019, 11:37:06 am »
You must use the insert in the end of the pipe.

This is not usually supplied with the fitting. It just pushes into the pipe and gives it extra rigidity (also ensures that very thin metal pipe is properly round). Not using these inserts is the main cause of push fittings weeping.

I don't think that's universally correct, plenty of online info will show push-fit on copper without using an internal sleeve. I'd agree that using compression fittings with non-metallic pipework will need an insert, and indeed some sources show inserts for plastic tubes for pushfit.

This may help.   https://youtu.be/6tgZKSahHhE
We are making a New World (Paul Nash, 1918)

Re: Push-fit Plumbing Fitting Innards
« Reply #9 on: February 08, 2019, 12:01:38 pm »
I do not think I have ever used pushfit with plastic without an insert but  I agree that copper pipe may be used without.  i suspect that cheap copper with thin walls may be a problem. 

Compared to copper though, plastic pipe and pushfit has made such a difference. 

Re: Push-fit Plumbing Fitting Innards
« Reply #10 on: February 08, 2019, 12:16:30 pm »
Check your insurance as well. Mine won't cover leaks from push fit plumbing for example. It was a specific inclusion.
I can also remember older policy documents that stated that all plumbing needed to be copper pipework, not plastic.

Re: Push-fit Plumbing Fitting Innards
« Reply #11 on: February 08, 2019, 12:27:00 pm »
With speedfit rather then hep there are different inserts for copper and plastic. One can be dissembled without tool one needs it but can't remember which way round.

Ref insurance most new builds use plastic. I know this from the amount we supplied and delivered when working at plumb center

Aunt Maud

  • Le Flâneur.
Re: Push-fit Plumbing Fitting Innards
« Reply #12 on: February 09, 2019, 10:29:53 am »
hep2o is the one wot needs a disassembly tool.