Another water hammer question (sorry!)

[Mmcgar]

Hi all
I have searched this forum but not really found any definitive answers. I put a post on here a few months back regarding banging pipes (that can often happen even in the middle of the night when no water has been running) iv had British gas out a few times n haven't got anywhere with sorting it.
My question basically is, as well as the banging pipes I also get water hammer at each tap plus my toilet. I have no access to the pipe chase where the pipes go upstairs (it's tiled over) is there a way to fix the water hammer without securing the pipes? I know u can get water arrestors, are these any good? Would I have to install 1 at every valve?
I'm getting a plumber out to replace my Stopcock as it doesn't quite fully close, he's mentioned a "stop /start" switch which can be installed instead of the stop cock, I googled this but it basically just looks like a light switch which would be more convenient to close but I can't see how it would help water hammer.

Thanks, I know this is 1 of those questions that must come up constantly!

 

[glasgowm8]

i have issues which may be similar. i have banging noises from right under the kitchen sink where the stopcock is. its defo the mains cold pipe under sink and it happens when no plumbing or heating or anythin is in use . i have had scottish water out to check the street mains incase its high pressure but i think i may have to get them in to check the mains pipe under the sink next

 

[Mmcgar]

Glasgowm8 I'm in Glasgow area as well, I got Scottish water out last week, they put a monitor on the mains in the street but haven't heard back from them yet.

I have a further question on this I'm hoping sone1 can help with, iv been reading online that the main stop cock should be fully open or fully closed, is this true? At the moment I have mine well turned down since I have high pressure, I might try fully opening it if it's a known cure however I'm worried the high pressure could make it worse

 

[glasgowm8]

apparently fully open or half open doesnt affect the pressure..just tge flow rate.

scottish water said my street mains was 4 bar which is fine so will keep an eye on the banging from under the sink this week before calling them back out. its weird cos all water hammer issues are usually when plumbing is in use! im sure mine is a high oressure issue but things like water pressure arrestors seem alot of money for something that shudnt be happenin in a 16year old house in a newish estate!

my stopcock ia fully open and then turned back a slight half turn as recommended on some sites.

 

[landyandy]

Very frustrating problem to cure.

In my experience shock arresters don't work very well at all.

I have found that turning the internal stop tap down also doesn't have much effect.

The water hammer problems I have cured have been by turning the external stop tap down.

Hope this helps.

Andy.

 

[Mmcgar]

Andy

Thanks for the reply.
I wasn't even aware there was an external stop cock, is this the main stop cock for the street?