Vibrator !!

[JPC]

That is "my pipes vibrate"

At night time.. when all is dark, i awake to the sound of a vibration. i look over to check the wife, however she is asleep.

Further investigation takes me to the mains pipe in the bathroom. It is vibrating. (-now..i have tried to think of anything other than my wifes vibrator to desc the noise/vibration but nothing comes to mind).

They vibrate at a rate of about 4-5 hits" a second.

this only happens at night thou ??

Is this something to do with pressure (ie not many households using water ?)

The boiler is not on at the time.

If i run a small drizzle from cold tap it stops.

What is this nocturnal vibration and whats the solution ?

cheers jamie

 

[ChrisR]

One of your float valve washers - wc or loft cistern. Probably a plastic valve. Changing the washer will probably stop it, changing to a brass valve would be better.

 

[JPC]

hmmm...

fitted my bathroom the other month. could be the new toilet ?

i'll isolate it tonight and see..cheers

 

[JPC]

check more indepth last night. the vibration is definetly coming from the mains stop cock. from both. i close the stop cocks and the vibration diminishedn but still there...the pipes in the bathroom only slightly vibrated however after closing down but the stop cock vibrated as much.
it must be the mains pressure and the fact that at night no many people are using the water.
has anyone come across this before ?
can i just turn down the street stop cock a turn or two ?
any ideas..the noise drives me mad..had to leave a tap drizzling last night to stop the noise !!!

 

[JPC]

by the way..its not coming from any cistern..all checked, isolated etc...
definetly the mains coming into the house at the stop cock is where its starts (both front and rear ones)
any help appreciated

 

[PEDANTICVINDICTIVEMAN]

If your not on a water meter leave the tap on to get your deserved sleep, not as if we are short of water at the moment is it.

 

[JPC]

turned the street stop cock down a bit..c what happens tonight.
and yes i'm on a meter...so cant leave tap on really...maybe some ear plugs ?!!!

 

[croydoncorgi]

Have you actually checked the valve in your cold-water tank (in loft / attic) assuming you have one?

Your description of the vibration / noise matches closely the noise of the arm of the valve moving up and down. (Water pressure in main pushes the arm slightly down making a small wave in the tank and letting a trickle of water through through the valve, wave bounces off the sides and when it gets back to the float, makes it rise up again, pressure pushes it down again, et voila, you have the noise. It tends to happen at night because mains pressure goes up a bit.

The answer (if this IS the problem) involves a piece of copper wire and a plastic cup! No - I'm not kidding!

 

[JPC]

Sorted the problem. turned the stop cock in the street down. pressure seems the same and noise has gone ( i believe..so far anyway as i have not stayed awake to await it).
could have been the washer in the street stop cock ?
i'll probably never know the answer
come on then..how would i have fixed it with the wire and cup if it had been the cold water cistern?

 

[dmccormick]

Croydoncorgi please can you elucidate about the cure as I think I have exactly the problem you refer to. We've just had new cold tank in the loft and after using water from it we get a resonant humming/vibration on the rising main into the loft; if I turn the stop cock off it stops and then if I turn it back on again it stays stopped. Thanks for your advice !

 

[dmccormick]

Have just found it somewhere else I think:
http://www.diydoctor.org.uk/tips/tipsplumbing.htm

 

[croydoncorgi]

Yup ..
The link http://www.diydoctor.org.uk/tips/tipsplumbing.htm shows exactly the trick I had in mind for silencing humming / buzzing tank valves.