Torbeck valve noisy at shutoff - sometimes

[news]

I have recently fitted a Torbeck valve to a toilet cistern, but am suffering problems with a loud 'bang' from the pipework when it shuts off. I have checked the archives and see that this problem has been reported before, but a strange feature of my installation is that if I dismantle and re-assemble the valve it remains beautifully quiet for about a day, but thereafter the hammer gradually returns to its original ferocity.

My water feed is from a tank, and no pressure reducer is fitted. If I restrict the flow with the service valve I can stop the noise, but the filling rate is then much slower than with the original ball c*ck.

If I can make permanent whatever I am doing by dismantling and re-assembling the valve it will solve the problem, but I have no idea what that is.

Richard.

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[Dave Liquorice]

Try the lower of the two supplied restrictors marked "LP" IIRC. The bang is symptom of the valve shutting off too fast which it will do with a high flow rate. You have to strike a balance between a reduced flow rate and the bang.

[Alec]

What I have seen being done is to add a vertical stub in the pipework that traps air in it to provide a "shock-absorbing" function !! Might be worth a shot for a half hours work.

[IMM]

Dedicated shock arrestors are available.

Not expensive. Just fit it on the offending pipework as close to the Torbeck as possible.

[news]

: Try the lower of the two supplied restrictors marked "LP" IIRC. The : bang is symptom of the valve shutting off too fast which it will do : with a high flow rate. You have to strike a balance between a reduced : flow rate and the bang.

But will that have a different effect to partially closing the service valve ? As I said, to stop the noise I have to reduce the flow rate so far that the fill time is unacceptable (longer than the original ball c*ck, which defeats the object). I'll try the restrictor if you think it will stop the bang at a higher flow rate, but I can't really see why it should.

Nobody has commented on my observation that dismantling and re-assembling the valve provides total relief from the bang for about a day, before it gradually returns. I've done this three times now with the same effect.

Richard.

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[Christian McArdle]

Fit a water hammer arrestor, such as BES #11355

You install it next to any problematic suddenly closing valve (i.e. Torbeck, ceramic disc tap, washing machine). It is basically a tiny pressure expansion vessel that is capable of absorbing the flow of water that is moving fast, but has nowhere to go when the valve closes.

Christian.

[news]

:> But will that have a different effect to partially closing the :> service valve ?

: Donno try it. Easy enough to do...

I tried it, and the flow rate was very low. There was no evidence that the result was any different from turning down the service valve. I *could* have tried cutting the restrictor in half, but by then I was losing the will to live....

So I have replaced the Torbeck with a Fluidmaster. I know that is not without its share of problems, but it seems to have entirely solved the banging. It is slightly more noisy when filling (largely because of all the air bubbles) but I am very happy with it so far.

It was more difficult to fit than the Torbeck. Despite appearing to need an identical installation, it lacks the internal 'seat' for the service valve connector to seal against. I had to fabricate a washer from an old grommet to make it watertight.

Thanks to those people who suggested various 'plumbing' solutions such as adding a hammer arrestor or air spring, but my DIY skills are not up to that level of complexity !

Richard

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