Will a water hammer arrestor solve my water hammer problem?

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I have a problem with water hammer. I know where the knocking is coming from but the pipes are not accessible.

I could live with it if it was just knocking when we turned taps off etc. but it knocks when the neighbours are using their washing machines and taps. I have turned the water pressure right down but the knocking continues and our electric shower goes cold with the washing machine on.

I was thinking that I could put in a water hammer arrestor after the stop cock to hopefully eliminate the water hammer from the neighbours. The pipes are all copper (Not sure of size yet) and I was planning on cutting a section out and putting a plastic push fit T section in with the arrestor on top.

Is that the right way to do it? Do you think this will work to eliminate the water hammer from next door? Anything I am missing?

Thanks in advance!
 
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Fitting an arrestor is treating the symptoms, not curing the disease. Ideally, you need to fix the pipes.

If this is going to be difficult, you can try shock arrestors, but it's not an exact science. If the loose pipes are upstream of the arrestor, you are wasting your time. The arrestor(s) need to be between the taps, etc and the loose pipes to intercept the shock wave.

To have the best chance of working you need an arrestor close to each tap or w/machine that causes the hammer. So, you will need several arrestors in your house and more in your neighbour's.

Even then, there is no guarantee of success. The only sure way of fixing the problem permanently, is by biting the bullet and securing the pipes.
 
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Fitting an arrestor is treating the symptoms, not curing the disease. Ideally, you need to fix the pipes.

If this is going to be difficult, you can try shock arrestors, but it's not an exact science. If the loose pipes are upstream of the arrestor, you are wasting your time. The arrestor(s) need to be between the taps, etc and the loose pipes to intercept the shock wave.

To have the best chance of working you need an arrestor close to each tap or w/machine that causes the hammer. So, you will need several arrestors in your house and more in your neighbour's.

Even then, there is no guarantee of success. The only sure way of fixing the problem permanently, is by biting the bullet and securing the pipes.

Thanks for your reply. I believe we have a shared water supply with the neighbours. The arrestor would be fitted just after where the water supply enters our house. The loose pipes would be after the arrestor. The pipes are un-accessible without ripping walls open.

I am not bothered about any banging that originates from us using our taps and appliances as at least we can control the banging in the main i.e. closing taps slowly. We have no control over the neighbours and it is driving us mad. I think it would be unfair of us to ask the neighbours to reduce their pressure etc. as it is our house that has the loose pipes.

For £50 it has to be worth a punt. Has anyone else had any success using an arrestor to stop water hammer that originates from next door?
 
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[The arrestor would be fitted just after where the water supply enters our house. The loose pipes would be after the arrestor.

Try, by all means, but there is a very good chance that you are wasting your time.

The shock wave starts at the tap or washing machine, then travels back down the pipe. If it hits the arrestor first, there's a chance it will stop the shock wave. If it hits the loose pipes first, they will probably bang.

If you have a shared stop tap, check it's not causing the problem. Sometimes the jumper inside can move about, but this usually causes a series of bangs rather than one. Sometimes, slowing the flow into the house can stop the problem, but if it affects your neighbours too, this may not be acceptable
 
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[The arrestor would be fitted just after where the water supply enters our house. The loose pipes would be after the arrestor.

Try, by all means, but there is a very good chance that you are wasting your time.

The shock wave starts at the tap or washing machine, then travels back down the pipe. If it hits the arrestor first, there's a chance it will stop the shock wave. If it hits the loose pipes first, they will probably bang.

If you have a shared stop tap, check it's not causing the problem. Sometimes the jumper inside can move about, but this usually causes a series of bangs rather than one. Sometimes, slowing the flow into the house can stop the problem, but if it affects your neighbours too, this may not be acceptable

The shock wave originates from my neighbours house and then travels into our house.

This is where I would place the arrestor. The water flows in the direction of the arrows:

neighbours house<--shared mains-->our stop tap-->arrestor-->loose pipes
 
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Ok, if you're going to only tackle the hammer caused by your neighbour's taps and w/m, not yours, try it.

The only thing is that shock arrestors need to be close to the cause, ie. tap or w/m, as in this video. You may get lucky.

 
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that could assist in noise reduction,buy 2 and give your neighbour one.

As long as your plumbing and your neighbours plumbing is in
stalled correctly this noise should never happen . :D :D :D .
 
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that could assist in noise reduction,buy 2 and give your neighbour one.

As long as your plumbing and your neighbours plumbing is in
stalled correctly this noise should never happen . :D :D :D .

I think it is safe to say our plumbing is a bit dodgy!
 
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If you use a pipe slice, you shouldn't need to deburr. (I'm going to get shot down in flames now from the deburring fanatics). Also, if your pipes are old 1/2" imperial, push fit fittings may not be suitable.

http://www.my-tool-shed.co.uk/p2378...medium=shopping&utm_campaign=allprods[/QUOTE]

Would it be as simple as wrapping a measuring tape around the pipe to find out if it is 1/2 inch? (That is possibly the dumbest question I have ever asked but I have no idea about plumbing and don't want to mess it up!).
 
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You'll need a vernier guage, but the difference between ½ " and 15mm is annoyingly small.

On compression fittings it isn't normally an issue, but on pushfits, it can be more of a problem.
 
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Hammer arrestor (sic) on Ebay for £22. No plastic connectors to be seen.
A decent independant merchant ought to be able to match that.
The rest of the bits to do the job ought to cost no more than a fiver, depending on choice of fixing method, plus a Pipeslice for around a fiver off ebay; £32 thereabouts.
 
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Sorry for dragging up an old post but did you ever fix your banging?
I've moved into a house with what sounds like the exact same problem and so wanted to know if the arrestor/shock absorber worked for you, and where you ended up putting it.
 
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