It's not a bad idea to add some water hammer arrestors at your WM. They're readily available as a no tool solution at most any big box store or hardware store. Sioux Chief and Watts and probably others make them. Get one that has the hose connections already on it, and it's just - unscrew the existing hose, screw on the hammer arrestor, reattach the hose. The safest thing to do is to always shut the water off to the WM when not in use...after all, those rubber hoses may eventually break.
Any quick-acting valve can cause a water hammer, but the larger the supply, the more noticeable it usually is. It depends on your water pressure, the actual speed of the valve closing, and how well attached the pipes/hoses are (some hoses will stretch, absorbing some of the spike, but that adds stress to them). If you ever look at the hoses to the WM when it turns the water off and you see the hose jump, an arrestor is a good thing.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014
Really?I would be shocked if a home refrigerator ice machine could cause much of a water hammer pressure spike (due to the low flow).
The plumbing code is not shocked by it though.
In a closed system, hammer arrestors need to be placed on all quick closing valves.
The toilet tank lever should be about 1/2" from the top of the overflow.
Yes I have.OK... I am shocked. Have you seen a case where a home ice maker (1/4 inch tubing I presume) was actually making noticeable water hammer?
And others have too. That's why the plumbing code "requires" hammer arrestors for them. Whenever I install water to an icemaker, I use the box with the hammer arrestor.
I guess you've never heard an icemaker filling before. Yes, I notice.
I heard from a Boeing Engineer that was being woken up throughout the night by his icemaker.
I tried to explain to him that he needed to install a hammer arrestor for that, and even gave him one to install. It sat in a drawer until his father-in-law came over and installed it for him. The FIL was a plumber, and knew what it was for. Anyway, my friend now sleeps through the night. Sometimes you need to lead those engineers through things. Books and codes don't mean much. They have to discover simple things like water hammer on their own.
Last edited by Terry; 10-09-2013 at 05:06 PM.