water hammer

6 Aug 2009
Reaction score
West Midlands
United Kingdom
Hi i have commented on this previously and this is an update and just to see if i can get a bit more advice!!

I have fitted a new wc and the equilibrium valve fitted was causing water hammer i presumed this was down to high water pressure

The water pressure was at 6.5 bar from the rising main!

I have fitted a pressure reducing valve hoping this would stop the water hammer and it hasnt I have reduced right down to 2 bar and still water hammer if i go to one bar i dont have enough flow

The pipes that are behind the toilet are boxed in but i removed a few tiles to make sure they were clipped properly and they are all solid no movement what so ever but when the toilet flushs there is a single bang that comes from what appears to be the pipes at the back of the wc once the valve stops filling and you can feel the pipes vibrate once this bang occurs.
All the taps are all pillar taps and are fine
I have tried turning the washing machine valves on and off quickly to see if the water hammer occured there and they are fine to im scratching my head really because the only thing i could think it could be now is the equilibrium valve as i have read they can cause water hammer because of fast they shut off. There is no adjustment on this valve for water pressure and no flow restrictor nozzle with it and it is a bottom outlet valve. I also have no room to fit a hammer arrestor behind the wc any ideas?
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the flow restrictor go's in the bottom where the cold mains water pipe screws on. useally get two with a new valve.
can you buy them seperate or can you only get them with a new valve

How does a equilibrium valve work i cant find any info on them anywhere
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can you buy them seperate or can you only get them with a new valve

yes they come with a new valve.


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