[Cultcab]

We have an irrigation system with 8 valves in the manifold. Every morning when the sprinklers run, we get woken up by loud vibrations from water hammering. Is there any way to prevent this?

 

[joecaption]

Add a water hammer or make your own.
https://www.google.com/webhp?source...8#q=water+hammer+arrestor+home+depot&tbm=shop

 

[Cultcab]

Where would I install this?

We had a pool built several years ago and we had the same water hammering with the autofill. They placed an arrestor on the line right where the autofill branched off of the main line and it worked great.

I have a 1" water line coming into the manifold - do I need to place the arrestor on that line before it enters the manifold?

 

[AllanJ]

Ideally the water hammer arrestor is placed as close as possible to the valve or other component that is generating the shock wave such as the rapidly closing, or worse yet, chattering and defective, valve.

But you may find that one arrestor on or just before the manifold works okay avoiding the need to have eight arrestors, one on each of the lines coming off of the manifold.