Water hammer due to jet spray

[JBR*]

Good morning. I am a new member here and would welcome any advice regarding a simple question.

I have recently installed a jet spray repeller in the garden which is operated by a built-in PIR sensor and is there to deter cats from doing a whoopsie on my wife's herb garden.

Whenever it operates there is a very audible water hammer knock, presumably because the valve closes instantaneously compared to taps, etc, which close more gradually.

I can live with the sound, but am concerned that repeated water hammer like this might damage some of the pipework or joints. Is this a possibility?

 

[brum]

Hi there water hammer is quite often caused by loose pipework try and locate were noise is coming from and fit extra clips if unsuccessful then a plumber will be needed to fit an arrester good luck..brum

 

[SJB]

Or the jumper in the stopcock or another cold tap. If I get it bad on a job I'll change the stopcock or stopcock guts and if that doesn't get it then I put an arrestor in as close as poss to whatever it is that's causing it.

the faff/demolition to make sure all the pipe work is clipped etc in a lived in house just ain't worth it IMO.

 

[JBR*]

Thank you Brum and SJB for your advice.
I'm not sure where the knocking is coming from, but I'll continue to investigate.
I am no expert but I have fitted taps before (using compression fittings), although I'm not sure how to fit an arrester or even what it looks like! Would this be an expensive job?
As I said, I'm not really worried about the noise, more the possibility of damage to pipework or joints. Is that likely?

 

[AWheating]

is it connected to a washing machine valve??
if so you could fit a shock arrester that fits between the mash mac tap and the hose.
if no wash machine tap the fit a compression tee (15x15x1/2")with a mini exp vessel/ shock arrester.

or turning you stop tap closed alittle may stop it but it will reduce the cold mains flow rate alittle.

 

[JBR*]

Thanks AW.

 

[gav85]

shot arrestor to cold main or mini expansion vessel as some people call them

 

[JBR*]

Thanks everyone. I would have replied sooner but it appears that the site was down this last day or so.

It has occurred to me that it might be easier for me, and possibly more effective, if I could attach a shock arrester directly to the cat scarer sprinkler. It has a (capped) threaded attachment for another hose (for multiple use). I just need to find an appropriate adapter. Actually, I'm sure I'm not the only person with such problems with a sprinkler, and I'd be surprised if someone somewhere doesn't produce such an adapter.

 

[JBR*]

I thought about getting one of these:

(Oops, for some reason the forum won't let me post a link to the item, but it is the same as the FIRST one that AWheating posted above. I know it is designed for attachment to washing machines, but I'd be happy to place it anywhere using adaptors if necessary.)

However, although the main culprit causing water hammer is the garden cat repeller, there is also a water hammer when the washing machine is running (although much less loud) and also when turning off a quarter-turn tap on the sink (although I've asked my wife to turn it off more slowly!).
Could anyone advise me the best location for this shock arrester to help with all causes of water hammer?