leaking cistern


I have toilet cistern that has a very slow drip from the bottom . I have checked the pipes entering & leavoing the cistern and I dont think the water is coming from them. If I am right then maybe there is a hairline crack on the cistern? if so .. is there a way to treat this even if I cant pinpoint the spot? I was thinking .. is there something I can coat the inside with after draining it, that will hopefully seal any crack?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
tomm wrote:

What is it made of (eg cast iron, plastic,ceramic,etc)?
I'd say that it is far, far more likely to be a seal. You could try food colouring as a crack detection dye - it should also help to locate a leaking seal, if that is the problem.
If there is a crack, then it really does depend on the material as to how it is fixed. The basic principles are:
1) drill a small hole at each end of the crack - to stop the crack from growing. 2) mechanically bond the two edges of the crack - to keep the crack from opening. 3) apply watertight sealant.
-- Sue
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

ok thanks.. will try the food colouring . It is ceramic by the way
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
tomm wrote:

Tomm,
Before you get out the drill etc as Palindrome has suggested - check for condensation first.
Scenario (presuming the tank is fed from the rising main) and you are not actually losing water from the tank:
Centrally heated bathroom (or toilet) plus cold water (made colder by the recent weather) in the tank will equal the aforsaid condensation - which will run down the side of tank and act just like a slow drip.
Try rubbing your hands down the outside of the tank to check.
This is exactly the symptom that is occurring in my bathroom at the moment and I get SWMBO to wipe the tank down every so often - well she did discover it some weeks ago and had the cheek to disturb me from a lovely warm fire with the shriek "come quick, there's a bloody leak on the toilet tank" - she'll suffer for that over the next few weeks now. LOL
Cash
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

well the last thing I would do is take a drill to the tank !! It may be correct advice but I am so useless I would make a mess of it for sure. To be honest I did consider condensation but I thought the water was gathering a bit quick for that. But maybe not ?>
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
tomm wrote:

I wouldn't worry too much about the drilling bit - that is really only relevant to plastic tanks and maybe to the odd cast iron one. As I stated previously, I doubt that you have a crack to fix, anyway.
Condensation can produce *lots* of water. Although I would use a tissue, rather than hands, to see if the surface of the tank is damp.
However, if you have dyed the water in the tank and the gathering water is crystal clear, then you will know that you don't have a leak to deal with.
-- Sue
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
tomm wrote:

Tomm,
A quick way to check - perhaps overnight - is to take the top off the tank and mark the water level with a pencil mark or similar and see if it has dropped by the morning.
Just take the precaution of telling family members what is going on and ask the first one to use the toilet in the morning to check the water level before pulling the flush.
Cash
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Surely if the level did drop, the cistern would fill back up again Cash? You'd have to strap up the ball valve so it didn't. If its leaking enough to be noticeable by the level in the cistern overnight, you'd probably be seeing the ball valve dripping anyway.
I'd go with Sue's suggestion - though if you don't have any food colouring handy, a "Blu-loo" cistern block will do the job. Just make sure you have some newspaper and an old tray under to catch the drips so it doesn't stain anything.
As with any leak, the source can be some way away from the drip. The last problem I had like this was a hairline crack in the plastic threaded bit of the ball valve where it went through the side of the cistern. The pipework wasn't level and someone had obviously overtightened and strained it. Sod to find - as it was clear water of course, and only leaked when there was very slight movement (e.g. when you sat on the pan!) but it ran down the cistern and under.
If your loo is the older type with an overflow, also check your water level. I've had a problem where the water level was slightly high in the cistern and the overflow union wasn't sealed properly. The level was just under the pipe so wasn't enough to be running out of it, but WAS enough to be leaking out the hole and down the side of the cistern.
HTH Midge.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Midge wrote:

You are correct - but I would expect that the OP would have sufficient intelligence to be aware of that.

Top posting corrected:
Midge wrote:

You are correct, but I credited the OP with sufficient intelligence to be aware of that!
Cash
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
tomm wrote:

Two things 1) Those blue blocks of disinfectant that go on the tanks are great for exposing leaks on white ceramic and plastic. 2) Is your toilet pan securely fitted? That caused my leak (in the same place as yours). As people sat on the pan it was moving slightly and breaking the seal and letting a tiny amount of water out. BUT when the pan was still there was no leak.
Just my 2p, that's the only plumbing experience I have.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

In my opinion, probably condensation, my close-coupled loo is just the same, especially in the recent cold weather. I note, the metal bracket that secures cistern to pan is now rusting, they should be of stainless steel, but I guess that is too much to expect from B & Q!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

In my opinion, probably condensation, my close-coupled loo is just the same, especially in the recent cold weather. I note, the metal bracket that secures cistern to pan is now rusting, they should be of stainless steel, but I guess that is too much to expect from B & Q!
Isn't this why its not recommended to plumb a toilet direct to the mains but to take the supply from the loft tank? ISTR the water from a loft tank is slightly warmer and therefore minimises condensation.
Mike
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 24 Feb 2009 10:05:19 -0000, Mike Rogers wrote:

That's OK if there's a cistern in the loft, but if the house is on a combi or such... Mine didn't have much condensation this Winter - might be because the window's open most of the time and the bathroom's at about 14 - 14C anyway.
--
Peter.
You don\'t understand Newton\'s Third Law of Motion?
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mike Rogers wrote: <>

That may be so. But we have two WCs - both back-to-wall type. Both cisterns are dry - always. One fed by mains water; the other by cold water tank.
(I did it this way so that whether the mains or the cold tank has a problem, we still have some flushing capability.)
--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Another simple but good option to rule out condensation would be to dry the outside and fill it with warm water. If it is leaking it will still leak when full of hot or warm water. Ifit condensation it will be nice and dry!!
C
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.