Big bang noise and pipe moving!

[Yanni]

I just fitted a secondary easy shut off valve on the water straight after the mains stop cock.

Now when the toilet sink tap is turned off there is a big noise and the pipe is moving inside the Hep2o valve.

Is this normal as I have never experienced this.

All the pipes are clipped ok and the right fittings have been used. Really puzzled.

 

[Madrab]

Correct pipe, correct insert, pipe fully home, pipe cut fully square to the insert? Can't say I've ever seen that either, almost as if the pipe isn't fully seated inside the fitting and it has room to move, which isn't right.

 

[Yanni]

Very strange. I fitted these before in another rental without any issues. I used the Hep2o collars that are not flat as the John guest but it is a hep2O valve so I never really mix. Bizzare. I might change the valve to a Pegler one compression type and see if that’s any better.

 

[Yanni]

Just called Hep2O and they told me is water hammer.

 

[Harry Bloomfield]

Just called Hep2O and they told me is water hammer.

Flowing water has inertia. Your so suddenly turning the water off, means the water's inertia suddenly has nowhere to go, so it will impact on the pipe movement.

 

[Yanni]

May I ask, what do you guys recommend, I am between a few options to stop the noise.

1. Insert a pressure control regulator valve to reduce pressure and if that does not work,

2. Install a small expansion vessel

https://www.amazon.co.uk/dp/B01LW1LR2O/?coliid=I4BF9UMRAVGUD&colid=CSRYJ5POSH6T&psc=1&ref_=lv_ov_lig_dp_it

Honeywell Home Pressure Reducing Valve 1.5-6 15mm x 15mm - Screwfix

Order online at Screwfix.com. Lightweight, simple construction. Designed to protect household appliances from excessive supply pressures regardless of fluctuating inlet pressure. Can reduce water consumption and damage from over pressurisation. 1.5-6bar adjustable outlet pressure. Supplied with...

www.screwfix.com

https://www.amazon.co.uk/Caleffi-525040-Mechanical-Arrestor-Prevents/dp/B00C9WB9J8/ref=pd_day0fbt_img_sccl_1/257-0663882-9057262?pd_rd_w=jKhbi&content-id=amzn1.sym.bfe06781-69ca-4a3a-9842-e535d2f2ae0e&pf_rd_p=bfe06781-69ca-4a3a-9842-e535d2f2ae0e&pf_rd_r=D684BFKG7P652DHSHA29&pd_rd_wg=ltggv&pd_rd_r=a8f927b8-3156-4945-b334-f1f5c82e191c&pd_rd_i=B00C9WB9J8&psc=1

What do people recommend?
I am looking for something that is low maintenance.

 

[Madrab]

Get a test gauge and test for high pressure if it's above 3 then a PRV should sort it. Hammer (hydraulic shock) is usually down to excessive pressure or loose pipes. Weird that Wavin would put it down to hammer, I still wouldn't expect the pipe to move in such a way. Can't say I've ever seen it and I've pressurised their plastic to some pretty high pressures.