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Arron
24th September 2003, 07:14 AM
Hi. We are currently doing some minor rennovations on a house built in 1970. A few days ago I started hearing a noise in the pipes. It is a regular knocking or ticking sound. Each knock is a second or so apart - and it sounds somewhat irregular. It dissappears when water is running but returns immediately the tap is shut off and persists whileever the water is not running. Turning the water off at the mains (the big tap and meter thing up by the front gate) stops it completely.

It is a low noise, easily drowned out by a passing car etc. During the day you can only just hear it, but at night it is quite annoying.

I have been under the house and stood next to the piping - the noise seems to be localised to the main incoming water pipe, but it is very hard to tell as I cannot pinpoint the exact source.

Can anyone suggest what it might be. I would like to know if there is anything I can do before calling in a plumber.

thanks
Arron

MICKYG
24th September 2003, 09:38 AM
Arron

I have encountered ticking noise in a water meter. Since the meter stopped and a new one fitted there has been no noise. Plumbing noise will transfer from other areas near you as well. It may just be water hammer usually when a tap is turned on slowly the pipes will give off a very annoying rattle. This can be cured with a type of chamber fitted into the line. (contact a plumber). It may pay you to check that all plumbing is secured and is not moving around in your building. If you have good pressure with your supply, pipes will often move slightly
as the load is varied.

The noise you mention stops when the water is not being used suggests that the problem is external to you and is noise being transferred from somewhere close.

There was a water rushing sound near here at one stage which could only be heard at night for about six months and when local council repaired a pipe about 150 meteres from here it stopped. Hope this may be of help,

Kind regards

Mike

BigPop
24th September 2003, 10:20 AM
Arron,
Sounds like there is water leaking somewhere and that the 'ticking' noise is the meter ticking over. You say that "Turning the water off at the mains (the big tap and meter thing up by the front gate) stops it completely" - doing this actually stops any water flow so to me it sounds very suspiciously as water leaking somewhere.

If it is the meter ticking and for it to be ticking over at that rate you will be having a substantial water flow and not just a drip or slight trickle.

Firstly I would ensure ALL taps (including HWS) are off and not leaking at all and then I would check to see if the numbers on the meter are actually scrolling over - if they are then you have water flowing somewhere between the meter and the house and need to find the leak (or where it is going to).


If not then do a thorough check under the house and in the yard to see if there are any really wet spots - if not then maybe need to call a plumber to try to solve your dilemna.

Zed
24th September 2003, 12:24 PM
G'day,

Im not a plumber so please forgive me if i'm wrong but here goes :

Sounds like classic water hammer problem to me. usually caused by not enough securing on the pipes in your walls and under your floors. eg some fell off due to age or now that you have installed ceramic taps or a flick mixer its become apparant that your pipes have not been installed securely enough.


Water hammer is caused by water suddenly being stopped whist in motion within your pipe system - it has kinetic energy due to pressure and flow - when you suddenly turn the water off (like with a flick mixer) it causes the pipes to move and voila! bang bang!!

Theres 2 ways of fixing that I know of that actually work :

1)
find the offending pipe and clamp the bastard so it dont move ever again - whilst your at it clamp the rest of 'em too. this can get hard if youve got hidden pipes in the gyprock walls or under low floors etc...

2)
install some water hammer arrestors. these allow water to flow into them when the spiggots or ceramic stoppers in a flick mixer are turned off stopping the flow. best installed next to a tap or even better install 3 or 4 of them in the network where they share the load.

There are a number of types available - one gives the opportunity to blow some air in with a bike pump! that acts as a diaphram...


These can be easily installed yourself or you could call a plumber.

you may want to install a pressure limiter at your meter (we have one that allows 650kpi <i think thats the unit of measure...> )

if you're unsure call a plumber and pay him to find and fix it - if he takes your money and doesnt fix it call him back until he does!

silentC
24th September 2003, 03:57 PM
We had an itermittent problem at our house with knocking in the water pipes. Couldn't work out why it happened when it did because we weren't always using water at the time. Often happened at night. Even checked with the neighbour regarding their dishwasher etc.

Turned out it was our dog, who used to sleep under the house. It's favourite spot was right up against one of the hot water pipes. The knocking was the sound of it banging the pipe against the floor while it scratched it's flea-bitten hide.

I kid you not!

But seriously, it doesn't sound like classic water hammer (son of a plumber, so I know these things :)) and could well be the meter. Alternatively, there might be something going on in your local area that is causing the noise. Sound will travel through water a fair way and when the water isn't flowing, this might be more noticeable. For the ticking to be the meter, there would have to be a fairly high rate of flow. You can listen to your meter ticking when the shower is running and it will be ticking around the one or two per second but a dripping shower wont produce a noticeable tick at all. A slow leak is unlikely to cause any noise from the meter per se.

Is there anything in the house that might produce a rythymic sound and that is in contact with the water pipes? Air conditioner compressor, central heating fan etc.. I'd also check with my neighbours to see if they've noticed anything.

You can get a plumber in but be prepared for a less than satisfactory outcome because it can be very difficult, if not impossible, to find the cause of the problem.

Good luck.

kenmil
24th September 2003, 07:43 PM
I sometimes hear that noise in my pipes, but only when a tap is turned on slowly. I therefore leap to the conclusion that you have a leak. (What you describe is totally different to water hammer.)

Arron
24th September 2003, 11:00 PM
thanks guys. After reading these I thought a faulty meter sending noise up the pipes was the most likely thing, so I went back to the house tonight. The noise had got louder and more frequent - so I went and put my ear against the meter. There was no noise at all coming from the meter. There also appears to be no leakage going on either.

I'm pretty sure its not water hammer. The noise is there when the water is not running. It is not something that occurs when a tap is turned on or off.

Has me baffled.

thanks
Arron

kenmil
24th September 2003, 11:24 PM
Are you sure the leak is not underground ?

gatiep
24th September 2003, 11:43 PM
From past experience I would put my money on a water leak.....either underground or a cistern or hws . Definately not water hammer which occurs when there is a sudden change in the state of pressure in the pipes

Have fun.....................keep turning

Marc
25th September 2003, 10:06 PM
Hi, I had exactly the same happening to me.

I went through all the logical assumptions in this thread, all very valid.

But you will find thta it is your main valve, right next to the meter.

The little piston wears out and starts swirling up and down into the tap. The water and the pipe amplify the sound.

Change it and the noise is gone.

The reason why MickyG's noise stopped is not because of the new meter but because the people who change the meter will change the washer/piston valve (what on earth is the proper name) as routine.

macca2
26th September 2003, 11:23 AM
Hi......I would call it the "jumper valve". But how would it swirl up and down if there was no water movement.

My bet is a water leak somewhere in the pipe on the house side of the meter.

I had one and eventualy found it by following the route of the pipe until I found a very wet spot in the sand.


Cheers

Macca

PaulT
26th September 2003, 11:45 PM
I cannot vouch for the story but I have heard of a case where a chap owned a double block of land. He built a new house on the 2nd block and sold the first one. What the new owner did not know was that the chap had extended the pipe over the fence line to a garden tap in his new garden. Both blocks were later sold and it was only many years later that the reason for the high water usage on the first property was discovered. The original owner was long dead by then.

Hope your neighbors don’t run the sprinkler a lot.

Andrew Nicholls
28th September 2003, 12:04 AM
There is no need for confusion here.
If there is a leak then the meter *will* be turning. If the meter is not moving- as you said it wasn't- then there is no leak- simple.

Water hammer can be caused by many different situations- too numerous to list. It is simply reverberation in the pipe.
You might call a plumber or fifty- good luck- you'll most likely need it.

You have two choices: 1) Try to source the cause(s) and correct them. or 2) Put an arrestor (or many) in the plumbing lines to minimise the effects.

Good Luck,

Andrew :)

Justin
28th September 2003, 12:25 AM
I may be wrong, but :

How many taps are connected to the supply ? I've seen water hammer caused by taps with washers that have gone dodgy. Not dodgy enough for water to leak out, but just enough to start a reverb effect in the plumbing. If you can be bothered, try changing the washers on your taps as a cheap faultfinding method........

HTH,


Justin.

P.S, your recent reno's didn't happen to involve plumbing or anything near plumbing did they ?

soundman
28th September 2003, 10:45 PM
I have had a similar problem for a while . I can assure all concerned there was no water consumption or leaks on our property.

I suspect one of two things.
Water hammer from a major user on the system or maintence procedure.

or

a dodgy pump or valve in the reticulation system.

the thing that convinced me is that the frequency (period) of the hammering was low much lower than any water hammer I have heard from a localised cause.

In many areas the water preasure at night can get very high & show faults not in the system during the day.

Andrew Nicholls
28th September 2003, 11:56 PM
There is of course another possibility:
It is quite possible the sound is simply being 'carried' along the pipework from a source totally unrelated to 'water hammer', as such. If you get along well with your neighbours- when you hear the noise next- put your ear to their garden taps. Same noise? Louder or more frequent? or Softer and less frequent? Is the noise only in your pipes? If you follow this train of thought and answer these questions you will go a long way to solving your puzzle. Water and water pipes will transfer some sounds a surprising distance. Well it's worth a try anyway. Maybe your noise is the dog next door; scratching fleas whilst under the house leaning against the pipes for support. Hey Don't Laugh- stranger things have been known to happen!!

Good Luck.

PS No I'm not - but that's only because I haven't got any beers left in the fridge!!

Cheers!:confused:

antman
29th September 2003, 11:55 AM
Not sure if this will help but....

I had a chat to the water and sewer boys here at Council and they tell me that often the stop cock where you connect your water to the mains has a leather washer. This washer will degrade over time particularily as it oscillates up and down with water flow. The boys suggested getting that changed as they tend to vibrate due to fluctuations in the mains line and even though you have no water flowing through into your property.

They also suggested that, less common, the meter non-return valve can 'rattle' due to fluctuations in pressure etc.

Just a couple of thoughts...

Anthony

Arron
2nd October 2003, 12:07 AM
Well I relented and called a plumber. It didnt sound very hopeful though - the first thing he said was 'yeah I have that at home too, it drives me mad'. He is coming on Friday - says he will do his best but doesnt have high hopes of finding the problem.

The water is currently off due to the hole in a pipe (subject of other post from me). After he fixes that it will be interesting to see if the frequency/volume of the knocking has changed.

Thanks for all your ideas anyway.
Arron

Big Mac
4th October 2003, 06:59 PM
I had this problem in the pipes in our house, i asked my brother who is a plumber,who said to sqeeze the washer shaft with pliers so the shaft is firm in the spigot. IT solved our noise problem.Try it .its acheep way out. Big Mac

robchronos
28th August 2007, 09:31 PM
Sorry to resurrect this 4 year old thread, but I'm wondering if you ever solved your knocking problem? The reason I ask is I'm dealing with the exact same issue and it has me stumped :(

bricks
31st August 2007, 08:55 PM
Sometimes float valves in your toliet cisterns can make this noise if they dont shut off compleatly. How to fix- Make the float lower so that the cistern doesn't fill up to the overflow pipe- take the lid off the cistern if its at the level of the overflow in the center then it has to come down a bit.:?

Otherwise check as much of the line as you can for something baning against it ( gate, fence panel, etc)

Disconnect the washing machine too- don't know why but they often cause strange water hammer type stuff due to the solenoid valves inside.