knocking pipes

[mynewoldhouse]

I just repiped a mess of old galvanized pipes with copper and now the Hot water line is making a loud crazy knocking but only when the shower/bath faucet is on, the other faucet on the line does not cause it to knock. I need some help:confused: !
thx
(BTW, it is not "hammer") and I do not have engery saver nipples in the line)
thx in advance

[patrick88]

how old is the shower valve?

[mynewoldhouse]

not too old but I am thinking that it could be the problem it is a one handle turn it from cold to hot thingy...do you think it it clogged or something?

[patrick88]

Some brands have a float in them that can flutter.

what brand is the valve. Some shower valves have built in shut offs one side may not be open all the way.

[mynewoldhouse]

I don't know what brand. I am going to take it off and get new value at the hardware store and see if that helps.
thanks
I will reply back after I work on it.

[GrumpyPlumber]

CLip the pipes, if you hadn't already

[patrick88]

CLip the pipes, if you hadn't already
never got that far was still looking for info

[mynewoldhouse]

I will take out the faucet tomorrow, but what is "clipping"?

[patrick88]

I will take out the faucet tomorrow, but what is "clipping"?

Hangers of some type. some are clips that hold the pipes to studs. This can be the cause of your problem.

[GrumpyPlumber]

BEFORE you take the time and effort to remove the fixture, make sure the pipes that feed it have been clipped down.
They'll rattle if they're just hanging loose.

[mynewoldhouse]

I "clipped" all the pipes really well..that sure helped..but the water pressure in all the showers, sucks..only on the hot side, cold is great. I tried to take a look at the values in the one handled faucet...but one faucet was all enclosed and I can't get to the values. the other one I opened and the first pullout part was clean and the rubber washers were in great condition, but there was an inner plastic piece that i couldn't get out....so what do I do, why is the water pressure so low in all the hot side in the showers/bath only?

[GrumpyPlumber]

Values?
If all your fixtures have low pressure on the hot, the trouble isn't likely each individual fixture.
Make sure the supply valve is fully open on your water heater for starters.