Failing Polyplumb fittings

[opps]

I got a phone call from a customer just over a week ago about a leak. Water (mains pressure) had been peeing through the guest room ceiling. I was tasked with finding the leak so that British Gas could fix it.

It was eventually traced to a polyplumb tee. One of the polyplumb pipes had blown itself out of the fitting (cold water).

8 days later I got another call from the same customer- another torrential leak through the same ceiling (warm water though this time).

I had to start punching holes in the still damp ceiling to eventually find the leaking pipe. Yet again it was a polyplumb tee with pipe that had blown out.



Is the customer just really unlucky?

It is a three story house with 45(?)mm MDPE supply and a Megaflow.

He has a total of four 22mm pipes running from the ground floor upwards, 2 are hot, 2 are cold. Only three of them have stopcocks though.

Previously I was able to isolate the leaking pipe using one of the stopcocks and reinstate water to the ground floor. This time however it was the pipe that runs out of the top of the megaflow that was supplying the leak. That pipe has no stop cock. I recommended that the customer ask BG to fit one.

The customer did mention that he had asked BG to increase the pressure to the shower in the top floor ensuite but I am not sure if that has anything to do with 3 year old polyplumb fittings failing.

Thanks in advance.

 

[Elkato531]

I would suspect that the pipe was not pushed fully into the fitting when installed. Polyplumb is my preferred push fit brand and I have never had fittings fail like that.
On closer inspection, the insert left in the fitting doesn't look like a polyplumb one, but I would still be surprised if a fully inserted pipe had popped out.

 

[polesapart]

+1^

Installer error more likely than material failure.

 

[opps]

I would suspect that the pipe was not pushed fully into the fitting when installed. Polyplumb is my preferred push fit brand and I have never had fittings fail like that.
On closer inspection, the insert left in the fitting doesn't look like a polyplumb one, but I would still be surprised if a fully inserted pipe had popped out.

The first blow out had a deformed star "grippy" ring, the second one didn't. I didn't look closely at the blown pipe in either situation, and cannot confirm that there are not scratch marks on the pipes.

Polyplumb do sell metal inserts though

Polyplumb PipeInsert Metal 15mm

Product Code PB6415M Polyplumb Pipe Insert 15mm Metal What makes the Polyplumb push-fit system so popular is the time efficient, no nonsense one step joint process. It can be installed quickly and easily and uses a high performance stainless steel grab ring which ensures superb joint integrity. It

www.hlilleyelectricalandplumbing.co.uk

You may be correct about the pipe not being fully inserted but I don't understand why it would take over 3 years to blow.

The first case (cold water) was whilst the customers were on holiday (heating was on though). No one was using their ensuite. The second time was after they had run two baths, but it was the hot supply to the shower that blew. The shower cubical is next to the bath but the tee is about 2 metres away.

 

[Exedon]

As above probably incorrect installation, but should have been pressure tested at first fix stage.
If fittings are suspect send them back to polypipe they will test them.
Some years ago we had a polypipe 10mm elbow fail and flooded a ceiling. It had been pressure tested.
When we took it out found found 2 of stainless steel 'teeth' on grab ring were missing. Sent back to polypipe within days there insurer agreed to pick up repair cost

 

[Elkato531]

I don't understand why it would take over 3 years to blow.

Inserted just far enough to get a grip on the pipe.
I once got called to an old style Hep2o fitting that had failed. Turns out that the grab ring had been installed upside down, possibly from the factory. It had still managed to hold for 2 years.

 

[opps]

Thanks guys.

I have to go back tomorrow to re-re silicone bits... I will pass the feedback to the customer.

Kudos to each of you,

 

[SandyLyon]

Almost certainly an installer error, Polyplumb fittings are “O” ring first / grab ring second, that means when the pipe is inserted it passes through the “O” ring first before passing through the grab ring.

If the pipe isn’t fully inserted it can hold on the “O” ring for some time before blowing off, this type of fitting requires a pressure test of 18 bar as opposed to 1.5 x working pressure or minimum of 10 bar.