Weird plumbing noises

Factual Questions
1

Went to my MIL’s today to check out what she said was a horrendous noise, which turned out to be coming from the plumbing. Sounded like a slow machine gun. When plumbing makes noise, let me tell you, it’s everywhere. I couldn’t figure out a source, so I turned off the water main and it stopped. Turned it back on and it was OK until my wife flushed a toilet. Turned off the water, quiet, turned it back on. Tried the same toilet and the racket started again.

I turned the main off and drained the whole system. Then I turned it back on and went around the house bleeding the air out. That seemed to take care of it but I told her, somewhat superstitiously, don’t flush that same toilet for a day to see what happens.

What causes that kind of noise? Mine will do that but just for one faucet in the whole house and just if I turn it on a trickle. Full blast is no problem.

2

You might need to restore or replace your water hammer risers. This is a common problem in older buildings.

3

Try these guys
forum.doityourself.com/showthread.php?t=222898

you may have to subscribe but there is no charge. Lots of info and only 1 weekly email at most.

I’ve nver had such a problem ddispite much do it yourself plumbing, but the suggestion is the toilet shut off valve may be clogged.

‘Replace the shutoff valve to toilet, along with checking the fill valve for debri.’

also this link

They suggest a quick closing valve may be causing the problem.

Don’t know what causes the hammering noise myself as I have never had to deal with such a problem. Hope a plumber will come along and explain.

Good luck

4

Great link, that does fit the symptoms. In fact what I did happens to match his advice even though I didn’t quite know why I was doing it.

Other searching, now that I know the term “water hammer,” has turned up water hammer arrester devices, which use a piston to isolate the air column. I don’t think we need to go there just yet.

Thanks.