On Dec 5, 4:50*am, buffalobill wrote:
On Dec 4, 11:11*pm, wrote:

I have a cold line on one sink and a hot line in another sink. *After
the water runs for a few seconds, the water "slams" off with a loud
bang. *I can then keep the valve where it is (not turn it back to the
original off position) and turn it again in the on direction and it is
fine. *The problem just happens from the initial off position to on.
They are old fixtures and one of them started after I tried to repair
a leak. *I changed everything from the shutoff valve, flexible copper
tubing, the seat and valve. *It does not appear to be house plumbing
problem as fixtures upstream and downstream work fine. *Any clues?
Thanks.

buffalo ny: *"water hammer" *your water pressure may be high. on hot
and cold water, sometimes an air chamber device will be installed so
the rushing water thru the pipe hits the water hammer device to
cushion the shock noise. *other times, the dead end pipe stubs of the
hot and cold supplies are extended vertically above the stops off a
tee sometimes hidden in the wall, and the air inside can cushion the
noise. if those air chambers are waterlogged they won't work, *you can
completely drain the house and let the water out of them. *that's the
cheapest remedy. or you can buy or make inexpensive *"Water Hammer
Arrestor". *search this group for those terms.
see also:http://www.naturalhandyman.com/iip/i...infwatham.html
theory at:http://en.wikipedia.org/wiki/Water_hammer

I don't think this is a water hammer problem. There was no problem
for 10 years, then immediately after I "fixed it" (I actually did fix
the leak but now I have added this problem) it starts doing this?
Plus it's only on the cold side on one faucet? Weirder things have
happened but I barely even get a knocking sound when the washing
machine shuts off. The think the other poster might be onto something.