Water Hammer Arresters

mcintoshmc · Mar 21, 2013

I will be repiping the house from galvanized to copper. Do people install these arresters if they experience water hammer, or a head of time as a preventative measure? If so, where should I put them as a preventative measure?

Also, I've read that they should be large than the supply line. Now am I teeing off the riser, or off the actual supply line?

IFIXH20 · Mar 21, 2013

You can use a laundry box & Ice maker box with the arrestor as part of the valves. Also install arrestor under kitchen sink for dishwasher. When plumbing to other fixtures (tub/shower valves, faucets, toilets) tee off risers with air chambers ( chambers 12'' -- 18'' long).

PioneerPlumber · Mar 21, 2013

These are usually only needed where a solenoid valve is located. Examples are dishwashers, washing machines and ice makers.

The photo showed one that can be fastened to a washing machine bib

mcintoshmc · Mar 21, 2013

So, in my case I would only need one on the hot/cold washer, cold for dishwasher, and one for the spigot in the backyard used for my sprinklers. Are they supposed to be same size of pipe or 1 size bigger. I read they should be bigger. Meaning 3/4 arrester on 1/2 line?

phishfood · Mar 21, 2013

I generally use the same size arrestor as the line that it is serving.

mcintoshmc · Mar 21, 2013

I also read those air chamber weren't good because I would constantly have to drain after the pipe fills up with water. Is that accurate?

IFIXH20 · Mar 21, 2013

You shouldn't have any problems with air chambers

IFIXH20 · Mar 21, 2013

You need arrestor at the laundry, fridge, and hot water to dishwasher. sprinklers usually do not slam off

stevemachine · Mar 21, 2013

In my area that aren't allowed to be used, but depends on codes in your area. We are required to use hammer arresters and not the air chambers. Technically speaking if you drained your system every once in a while (maybe yearly) I think air chambers would work, but I'm not certain on the air chambers.