Hissing coming from pipe leading to toilet

[magicdaps10]

As it says really.

There is a hissing noise leading to my toilet but no visable leak.I have turned of main water supply and it stops and when i done this opened all taps up to release any air or existing water.....i turned supply back on and hissing is still there.

Any suggestions to what it could be or problem solves or fix?

Could be the toilet itself even though i think the sound is coming from pipe?

Many thanks and any help would be appreciated.

 

[danielp]

the sound can go through the pipe even if the ball valve is letting by a little bit if thats not letting by it can be a leak depending if the pipe is buried u wont see it

 

[magicdaps10]

So if it were the ball valve would it then stop when i turn the water supply to the house off? becasue as i said when i turned water supply of it stopped.

There is no increase of water mind in tank and no dip in water level in the cistern suggesting there is a leak into the toilet.

 

[Dannypipe]

Uh oh. You've got a leak!

If turning off the main stops to hissing, then you have def got a leak. If you can't see it, then it must be buried or behind a stud wall (etc) Or it could be a tiny leak, that is just spraying a mist behind the basin/toilet etc. Look for damp patches. I'd be tempted to shut your water off at the rising main when you go to bed tonight. Just so you don't wake up to a small flood.

Good luck.

 

[danielp]

well if the toilet is off mains water than it will stop yer

 

[magicdaps10]

If it were the ball valve then surely it would effect the water level in the cistern?

The hissing as been going on for a few months now and pipe comes up through the floor so i think it below concrete and there are no signs of water!

 

[Dannypipe]

If the leak were at the ballvalve, then you'd see it quite obviously!

No it would not effect the level of water in the cistern.

A ballofix valve is for isolating a single appliance (i.e toilet) so you can service the valve in the cistern without shutting off the water to the whole house. (rising main).

The level of the water in the cistern is controlled by a seperate valve (with moving parts). There are a multitude of different valves in toilet cisterns. A decent plumber will be famililar with all of them.

By the way, copper pipe buried in concrete often fails. The lime in concrete will attack the copper if it isn't protected, and leave it with tiny pin holes in it. They will indeed hiss. Hope this helps, even if it is all bad news!

Just so we're on the same page, this is a ballofix valve -

And this is one of many toilet cistern valves - Syphon -

Finally, you also get quite a few of these, also a toilet cistern valve - Torbeck -

Ball Float Valve -

 

[magicdaps10]

Ok,the ball valve is the plastic looking nut thats at the end of the float arm?

When i flush and the cistern fills there is a drizzle from there and when filling stops there does seem to be drops coming from there every say 30secs to a minute.

I have tried tightening it but still dripping.....it looks to be easy to take off and replace.
so a little leak like that can make a hissing noise and pressumably make it sound like the pipe was hissing also?

 

[Dannypipe]

Um - no but close! See pics above. Sounds like you have a torbeck valve, on mains pressure.

The diaphram in the valve may need replacing (5 min job). Then it won't drip. Or the last plumber may have put the low pressure coil in the bottom of the valve. (They come with high and low, and it's down to the plumber to fit the right one.

Little leaks do often hiss. It's obviously high pressure water. So please take care. If you make a mistake, you could have a lot of libberated water!

To service a drippy Torbeck valve, I isolate the water.
Open the valve up and change the diaphram. Switch water back on and observe. If it still drips, then most if the time, I just change the valve altogether.

Not an expensive job mate, if you get someone in, it'll be £50 tops.

 

[REDSAW]

firstly,
back of the blue nut to where it was origionally, as these can blow of if over-tightened leaving you in a right mess. i have stood next to one when it blew.
next,
flush toilet, wait till it fills fully. then when it hisses gradually lift up the float and see if it stops hissing, dont over do it thou.
finally,
if this stops the hissing then your dia washer has worn for £3 change the lot.
or if not you have a leak further down the system that is sounding through the toilet simillar to the way a trumpet works when u blow.
call a plumber.

 

[Dannypipe]

Yup, if I were him, I'd not start messing with my toilet at midnight!! Switch the water off at the rising main, sleep on it. Then sort it tommorow. Good luck, I'm gonna go catch some Zzzzzz's. Let us know what it was. My money is on diaphram.

Cheers,

Dan

 

[Bernie2]

The problem is sound travels through water very well. A hissing noise is usually a leak. But if you think it might be the ball valve, lift the arm to shut the water off into the cistern to see if the noise stops. If it does renew the ball valve as suggested. If it doesn't you've probably got an underground burst somewhere under the concrete. No easy way to find it if its not showing above ground.
Its dig a hole in the concrete time or reroute and install a new main above ground from its entry point, picking up the branches as you go along.

 

[magicdaps10]

Right lads....im now none the wiser here!

Found the pipes that run to toilet,they run behind my kitchen units.I followed the pipes from the water mains cut off to the toilet and no leak and im convinced the leak is not from the toilet itself...convinced i say!

As the pipe enters the toilet room the pipe takes what i would say a z shape.The pipe also runs to the sink but yet no noise from the sink pipes so i think that there is air in the pipe that leads to the toilet...is this possible and how do i attempt to get that air out?

Any solutions?

P.S-As stated in an earlier post when i turn water mains off the hiss stops so i assumed it was obviously sourced from there.I did think it could be a leak outside but why would the hiss be in my toilet room and not my kitchen!?

 

[danielp]

to me its most certanly the ball valve not quite shutting of it only needs to be open a tiny little bit to make a hissing sound change that and i bet it will stop

 

[Puddle]

Quick possibility
plastic ball valve has small crack in seam

 

[magicdaps10]

Ive turned water valve off to toilet and its still hissing.wouldnt it stop if valve to toilet is off?

Only stops when i turn the water mains off.

 

[REDSAW]

have you got an outside tap near the kitchen?.
if so that could be letting-by, or leaking slightly into cavity,, isolate to check.
you may not hear hissing in kitchen due to accoustics. when you take of a cistern lid with external o/flo you will hear outside noises like a loud speaker yet the kitchen has poor accoustic levels.

 

[magicdaps10]

Yes i do have an outside tap.That does make a squeeling noise when i turn it on outside and rattles a little.Although when i run that tap it still hisses in the toilet.

My toilet is the new plastic diaphragm valve so changed valve and still hissing.Should i also change the water in pipe that goes into the cistern,would that be a possible culprit?