Help with vibrating pipes, water hammer

[fredley]

I have constant, severe water hammer - loud (~60dB) vibrations in the mains pipe. They were originally started by flushing the toilet, stopping soon after but now they are constant. These vibrations do not stop when the cistern is full, nor do they stop when the valve to the toilet is closed (it is the only thing connected to this inlet, which runs from my floor to the ceiling otherwise uninterrupted, from the flat below to the flat above).

https://i.stack.*********/01tAS.jpg

Flushing my toilet is, afaik, the only thing that started the water hammer before. I used to be able to stop it, by gently repeatedly pressing the valve in the cistern, opening and quickly closing it. It took ~1 minute of attempts to stop the water hammer. Sometimes it would flip between rattling/vibrating when I do this until it stops. It started again immediately upon flushing the toilet. However now it is stuck vibrating and nothing I can do will stop it.

https://i.stack.*********/Uumnr.jpg

When the noise was stoppable, if I disconnected the filling system (Geberit) from the hose and then reopened the valve to the toilet, the hammer started again (so it's not the filling system - it could be the bit stuck on the end of the hose?).

The valve to the toilet is full open, closing it doesn't stop vibration once it's started, fiddling around with it hasn't achieved anything so far.

My question is:

Is this problem something I can fix myself/with a plumber (e.g. with a water hammer arrestor?), or is it definitely something wrong with the building's supply (e.g. the pressure regulator to the mains pipe from the street supply?). It's definitely caused by the toilet flushing, but I can't identify anything within the toilet that's at fault.

I'm losing my mind since this has been going on for a week already and the building maintenance can't get anything done until the 3rd. If it can be fixed or at least stopped or remedied before then I really don't care how much it costs.

I've had a plumber in already who cost £90 and achieved nothing, so I'm keen to get a better idea of what the actual solution is likely to be before hiring someone else.

Let me know if there's any other tests I can perform, or pictures/videos I can provide.

 

[JCplumb]

Water hammer can be caused by valves or badly clipped pipework or a combination of both.
If the problem originated from your w.c. filler then that would be the first thing to replace, it may solve the issue, if not then at least it has ruled it out.
It could also be the stop tap to your flat, or even a stop tap further upstream from your flat.
If the new fill valve doesn't solve it then your stop tap and pipe clipping needs looking at, an arrestor could be considered after ruling out as much as possible, it 'may' work but they do eventually fail so best to try and fix the issue rather than put a plaster(arrestor) on it.

 

[JCplumb]

And is the hammer a knocking sound or a humming? If it's a humming then it's a valve and not pipe clipping issues.

 

[fredley]

It's humming, could it just be the valve on the pipe then? It's a standard compression valve as far as I can tell. Is it odd that the humming continues even with the valve shut?

 

[fredley]

Is there a way to at least temporarily stop the humming until a proper fix can be made?

 

[chris watkins]

It is not the WC cistern you have proved that by disconnecting it, unless you have access to the mains supply up & down the building then I am afraid it is going to be very difficult to find what is causing the problem, it sounds like its a valve of some kind vibrating that is to blame.

Does it stop at night when little or no water is being drawn ?

Can you feel the pipe moving? from the photo it looks old so I take it has only just started doing this, it is therefore not likely to be the clipping.

Unfortunately installing a shock arrestor or other vessel is unlikely to cure the problem as these are used to cushion out pressure shock waves traveling up & down pipes, this sounds more like vibrations.

I can only suggest trying to muffle the sounds with pipe insulation etc. until the cause can be tracked down.

 

[fredley]

Thank you very much for your help, looks like this new year (my first holiday in months) isn't going to be that relaxing... :-(

 

[kozak1968]

If you try isolating each tap or outlet then you may find out where the problem lies. Kitchen sink taps are a favourite one, you might not see anything dripping very much but I've seen a few cartridge types with this problem.

 

[fredley]

Hi kozak, unfortunately the toilet is the only thing attached to this line, so I've got nothing to isolate!

 

[chris watkins]

Where does the rest of your water come from, the kitchen sink cold should also come off of the mains somewhere.

If the mains runs to a storage cistern upstairs then try running off lots of cold water via bath & basin to see if the increase in flow rate has any effect.

 

[fredley]

There's another mains pipe at the opposite corner of the flat that feeds everything else (including the rest of the bathroom equipment). No vibrations in it.

I don't know if there's a storage cistern or anything, I can't run anything off except through the toilet, which I've tried (unscrewing hose and letting it run free) and it didn't stop the vibrations.

 

[joni os]

If not fill valve then fittings leading to it seem prime suspect. Slotted screw on ball valve can detach leaving valve stuck in position or maybe inline flow restricter . Meanwhile, Resonance of pipework can be altered with strategically placed jumbo car wash sponge or folded towel.

 

[fredley]

I've not had any successful attempts at altering resonance of pipework, I've tried holding it this way and that to no avail. Wedged towels etc. damp the noise but don't stop the vibrations.

I've managed to kick it into a quieter mode by holding the valve open (closing it, even with the main compression valve, causes it to be loud again). Maybe it'll see me through the night...

 

[chris watkins]

I've not had any successful attempts at altering resonance of pipework, I've tried holding it this way and that to no avail. Wedged towels etc. damp the noise but don't stop the vibrations.

I've managed to kick it into a quieter mode by holding the valve open (closing it, even with the main compression valve, causes it to be loud again). Maybe it'll see me through the night...

Good luck, best we can do by the sounds of it (no pun intended).

Only suggestion I have is getting some ear plugs but maybe a bit late tonight.

 

[joni os]

Blue sky thinking:- Isolate water to WC and flush with bucket filled at kitchen sink until cause identified.

 

[fredley]

Wouldn't really make a difference - the vibrations continue even when the WC is isolated, and my main concern is stopping them really.

 

[joni os]

I'm meaning physical isolation. Part the pipework at iso valve. Your posts mention vibs start with your flush and do not mention vibs caused by adjacent flats on same pipework. If this stops vibration replace fill valve and everything in between. If not vibs are independent of your cistern,although reading posts this does not seem to be the case.

 

[king of pipes]

May not be your toilet it could a problem in the flat above if it is supplied off the same rising main surely it's the landlords duty to get it repaired unless your the owner of course

 

[fredley]

I own my flat, but no others. Have tried contacting owners of above and below, nothing back yet, and their tenants are all out. We've ended up moving out for the rest of the holidays, it's literally uninhabitable,and nobody, not even the maintenance company will help us.

 

[king of pipes]

You need to take some professional advice contact the maintenance company after the holidays as they can gain access to above or below properties, also contact the owner of the building and explain your situation best of luck with your problem.

 

[fredley]

OK, so the people in the flat below (ground floor) came back last night, and the noise stopped the moment they turned on their taps. The noise still starts sometimes when they're using stuff down there, but stops soon after. The problem is probably in their flat. I've now got the details of the letting agent for the flat below, and will get onto them on the third.

Thanks for your help everyone!

 

[turnpin]

Thanks for the update fredly hope you get it sorted......regards Turnpin:smiley2:

 

[king of pipes]

Glad your getting somewhere fredley regards w

 

[king of pipes]

Glad your getting to the source of the problem fredley