Loud vibration in pipes

[Riverman]

We have loud vibrations in our pipes. It happens when either of our showers is used about 10-20 seconds after the shower is turned off and stops after 5-10 seconds. It is very bad in the morning and gets better through the day. By late on the day it doesn’t really happen.

There is a shower pump which was recently replaced as it was faulty. We hoped replacing it would help but it hasn’t.

It seemed to begin when our builders left after they put in our new kitchen but our plumber doesn’t think it would be from work they did.

the noise comes from below the floorboards upstairs, the airing cupboard where the cylinder is and down some boxed in pipes in the downstairs toilet.

Does anyone have any advice please. The plumber we used who I like and seems to be pretty good tells me he’s stumped by it.

Thanks.

 

[Keefy]

I know this is a late reply but I've only just come by your post.

Usually with this kind of 'vibrating noise' I check the diaphragm washer in the toilet cistern, if it's split or misshapen I swap it for a new one which resolves the issue 9/10. If you're still experiencing the problem check that first.

 

[Riverman]

Thanks Keefy. I will have a look at that.

I have noticed that it doesn't happen when only cold is on from the shower / shower pump but when the hot water is called for.

Is it still worth checking the diaphragm washers in the toilet cistern?

I just thought it must be something to do with hot water?

 

[Chuck]

Does anyone have any advice please. The plumber we used who I like and seems to be pretty good tells me he’s stumped by it.

Have they checked all the pipework is securely clipped at the correct intervals?

Otherwise, it might be worth checking the supply pressure and fitting a pressure reduction valve if it's high. Plumbing becomes more sensitive to water hammer as the pressure. Part closing your stopcock may calm things down a bit. If this is the case, it's possible that it was traditionally left part closed but your kitchen fitters left it fully open after they'd finished work.

 

[Riverman]

Thanks Chuck. I tried that and had no joy. I’ve read elsewhere that it could be a ball valve in loft tank. It’s really doing my head in.

 

[Riverman]

So I checked again and it does seem to be a cold water pipe up to the loft that is vibrating. That does make me think it is water hammer in that pipe and something to do with mains pressure to the loft. It makes sense that it is the float ball valve in that tank. How will I know if it needs replacing? Or should I just replace it anyway.

 

[cjg]

replace, there not dear, had one once took ages to find, and it was a pain!!!!!, to find,
replaced and it stopped.

 

[Riverman]

I found the float valve and there was water coming out of the little plastic outlet tube. Don’t know if that’s normal? Anyway it was definitely that valve as I could feel the vibrations and when I tightened the outlet tube the vibrations stopped. Massive relief! If it stays fixed great if not I’ll change the valve. Thanks very much for all your help I’m dead chuffed.