Noisy pipes on cold main

[toonlara]

I am perilously close to losing my mind - so any help appreciated!

About a month ago a vibrating sound started on our cold mains (copper pipes).

This noise will often go on for 12-24 hours, always a loud rumbling sound that you can feel in the pipes.

I am in a maisonette, and believe the cold mains splits in my downstairs neighbours property - but Southern Water have yet to confirm. Downstairs say they can't hear it, but they are a touch mutton and with current situation I don't feel like pushing too hard to go in and listen.

I've had a plumber out multiple times, we've clipped pipes, checked toilet cistern, old water tank in loft, changed tap to washing machine.

Southern Water initially said not their problem (quelle surprise) but I've managed to get them out and they'd said it's not in the street, but are now considering changing my meter and return valve.

I guess my only doubt on this is that it happens nearly exactly every three days, starts at approximately 10am, and stops as if my by magic at the same time the following day.

Turning the water main off in my property stops the noise, but I can't have water off for 24 hours at a time.

Happy to spend to sort the problems but don't want to spend a fortune and still be left with this noise!

I noticed a couple of people seem to have had similar issues but sadly haven't updated their posts with their resolution.

Has anyone got any other suggestions as to what I can check?

 

[Aquarius]

Does it happen after anything, eg hot water draw off, using a specific appliance? Do you have 1/4 turn taps? Is it specific to one particular area?

 

[toonlara]

Does it happen after anything, eg hot water draw off, using a specific appliance? Do you have 1/4 turn taps? Is it specific to one particular area?

Nope, no water used when starts. I believe I have 1/4 turns. I'm in a maisonette, so very small area, sound is loudest in kitchen/bathroom (which are next to each other) but can be heard in bedroom where boiler is.

Thanks
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Update: today we have sailed past its normal stop time, straight in to day 2.

 

[PETE 123]

May be a ball valve letting by or something overflowing in tank. So water runs all the time.

 

[toonlara]

May be a ball valve letting by or something overflowing in tank. So water runs all the time.

This is what my plumber thought, but has checked the disconnected tank and ball valve, as well as the loo and cistern

 

[PETE 123]

Leak under floor maybe (if you got a water meter see if its going round) when all off.

 

[toonlara]

Leak under floor maybe (if you got a water meter see if its going round) when all off.

Thanks for suggestion, checked meter and not moving, also upstairs maisonette so any leak under floor would be going in to downstairs. Most baffling noise ever!!

 

[Aquarius]

Are any off the taps dripping? Are you able to isolate any taps or toilet? Try running a tap and check if any others start to drip/run.

 

[toonlara]

Are any off the taps dripping? Are you able to isolate any taps or toilet? Try running a tap and check if any others start to drip/run.

None are dripping (noise still happening).


Turned each one on individually and not causing any of the other to drip or run.

Thx

 

[Aquarius]

Are you able to isolate the kitchen taps? Then if still noisy, isolate the bathroom basin taps and wc cistern?

 

[toonlara]

Are you able to isolate the kitchen taps? Then if still noisy, isolate the bathroom basin taps and wc cistern?

Oh! I see what you mean, we think so, so next time we get a loud series of rumbles we'll check that out!
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Oh! I see what you mean, we think so, so next time we get a loud series of rumbles we'll check that out!

So, isolated all except kitchen cold, as that doesn't have an option to isolate as is next to meter and stop and the noise remains!

Thx

 

[PETE 123]

Had job where the cold was letting bye on a shower unit the cold was on mains and hot tank fed so water was passing non return valve and going into loft tank. Just clean the non return valve all ok after. Something like this may cause a noise.

 

[Aquarius]

Oh! I see what you mean, we think so, so next time we get a loud series of rumbles we'll check that out!
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So, isolated all except kitchen cold, as that doesn't have an option to isolate as is next to meter and stop and the noise remains!

Thx

Does this include bath taps? So obviously it’s an issue separate from the isolated parts of the system.

 

[toonlara]

Does this include bath taps? So obviously it’s an issue separate from the isolated parts of the system.

Yup, did bath taps as well. Noise remained regardless!

 

[Aquarius]

So could be cold on tap, stopcock issue or something else

 

[Chuck]

I think you need to widen your search area.

The vibrations you hear/feel have to get their energy from somewhere, usually the flow of water. If you have monitored your water meter while the humming is active and it really is not moving over an hour or so then the root cause most likely lies outside your dwelling.

Best thing to do is to talk to your neighbour and ask if your plumber can perform similar checks in their part of the house. Start simple, is their water meter creeping round while the humming is happening? Is the humming audible in their flat? Does it stop when they close their stopcock? Does shutting their stopcock also stop it in your flat? Does shutting your stopcock stop it in their flat? The key question here is 'Is the source of the noise in your neighbour's flat or are they also a victim of pressure oscillations in the supply?'

Are there any other neighbours you can ask if they have noticed anything.

The duty cycle (on at 10AM, continuous for 24 hours, then off for a couple of days) may be a clue. Do the neighbours tend to do a load of washing around 10AM every few days? Is there a factory / industrial unit near by that might be running a batch process?