On Dec 6, 4:54*am, ransley wrote:
On Dec 5, 8:21*pm, Fleemo wrote:

We just had some kitchen renovation done, adding lighting cans to the
ceiling. The contractor had to reroute some of the waterlines that
were run up there to make room for the lighting fixtures. Only thing
is, now the pipes make a kind of loud shudder when the kitchen faucet
is turned off. *Didn't used to happen. *What's the cause of it and
what can we do about it?

I think what you have is called air hammer or pipe hammer?, Its common
to extend a piece of capped pipe up 12" at the sink plumbing area to
make a "air bumper" , ones you buy are mechanical and will eventualy
fail. A air bumper I think its called just cushions the shock of
turning off the water. Mine are behind the wall and standard to do by
a plumber here. You city code dept will tell you if its mandatory or
recomended so you wont have to pay to get it fixed. If you see its
going to cost you you can still get a permit and they will make him
fix anything that fails. Point is you paid for a good functioning job
and didnt get one. If a guy missed that I would want everything
verified as correct and to code. Getting a permit is always thought of
as a wastefull tax by homeowners, im a contractor, people I hire try
to rip me off every day and permits and free inspections catch what I
miss. A permit gets you free inspections to cover you from being
ripped off in the first place. Next job, get a permit and dont pay
till it passes, is normal business practice.

Mark-

Air chambers...a length of pipe extended some distance above the angle
stop location to act as a pressure pulse absorber have a couple
shortcomings;

They need to be rather tall to retain useful air space, when they go
from atmospheric pressure to system pressure they can lose over 75% of
the initial air space depending on system pressure.

the air in the air chamber eventually gets absorbed into the water &
the air gap goes away requiring them to "drained" ....an easy process
but most homeowners wont do it.

"mechanical" water hammer arrestors do eventually do wear out but the
piston style ones made by Sioux are guaranteed for the life of the
plumbing system and were tested to verify life beyond 500, cycles
without failure and are rated for concealed installation. Despite
this guarantee and testing, I prefer to install them such that they
can be easily unscrewed and replaced.

air chambers or water hammer arrestors all aim to add "distributed
compliance" to the plumbing system; a "soft element" not unlike a
car's shock absorber or an energy absorbing bumper.


OP- I would suggest that before you get too heavy handed with the guy
who did the work......just give him a call and see what he says about
the problem. If he's a stand up guy and you didnt hire him solely on
price (did you?) and you didnt beat him down on price as
well.......I'd bet that he'll take care of the problem.

If the piping is sealed up into a space with no current
access....well, then this might be a bit more problematic.

please let us know how this all resolves

here is is a pretty good discussion of water hammer & the remedies

http://www.ole-eng.com/blog.htm

scroll down about 1/3 of the page & click on Water Hammer topic

cheers
Bob