Noisy when taps turned off now

[jacobball]

We've had a new bathroom fitted and a combi boiler installed, from the old tank and hot water cylinder system.

What we've noticed is there's a loudish knocking noise whenever the bath taps and basin are turned off.

Could this be to do with the higher pressure? Any ideas how to quieten it as it is annoying!

Thanks for any help available

 

[screech]

Install a mini expansion vessel on the cold inlet to the boiler

 

[jacobball]

is that like a shock arrester that you can get from Toolstation? Will it be ok that far from the bathroom?

 

[jacobball]

the cold taps also do the same, will 1 mini vessel be ok for both if I fit it before the tee off into the boiler?

 

[jacobball]

what type of mini expansion vessel would be suitable? Toolstation don't stock the shock arrester now