Cold water tank overflowing

[pandaman]

Our cold water tank has been overflowing, mainly at night but in the day today also. Last night I turned the water off to the tank and on again this morning. My plumber can't get until next week. Looked at YouTube videos which seemed to concentrate on just changing the inner part of the valve. Got one from Screwfix, tried to remove nut on valve, no luck, sprayed penetrating on but it won't shift, I think it was changed about 20 yrs ago. YouTube make it look easy don't they. Thought about undoing the outside nut to water supply but can you reuse that with ptfe tape or sealing compound? Also the tank is huge, 35 yrs old, why make them so big. Also can someone tell me why the overflow pipe looks like it does, see photo, and what is the thing on the outside of the tank on the overflow pipe, again see photo. Any advice welcome.

 

[ChrisJP]

Your pictures don't seem to show any sort of float valve in the tank. If it's continually passing water, the easiest action is just to replace the entire valve

 

[denso13]

And it's a cistern, not a tank. Sorry.

 

[HERTS P&D]

What is a CWST?

Cold water storage tanks (CWST) are what feeds the sinks, hand wash basins, showers, toilets etc within various types of buildings.


Andy

 

[denso13]

Yes, a lot of amateurs get it wrong.

 

[Johntheo5]

And it's a cistern, not a tank. Sorry.

I was wondering how long it would take to correct that, still just over 2 hours isn't bad, any time I called it that, a CWST, I was admonished before the ink had dried on my posts, for over 60 years I've allways associated a cistern as a very small tank like a toilet cistern.
Is it now correct then to call it a CWSC??.

 

[denso13]

I've allways associated a cistern as a very small tank like a toilet cistern.

A cistern has a lid and ball/fill valve.

I was admonished before the ink had dried on my posts,

My reply was a bit tongue in cheek but many years ago my college lecturer always got annoyed at two particular things. It's a cistern not a tank, and the only time the rising main term is correct is when a water main goes up a hill.

Amazing the things that stick in your mind.

https://www.waterregsuk.co.uk/downloads/public_area/guidance/publications/general/guidance_2024/booklets/cold_water_storage_cisterns_feb_2024_v_1.1.pdf

 

[ericmark]

This is a cistern, very interesting, one can walk around it, there is a raised walkway, see more here clearly a cylinder is round, as to tank, likely covers all.

Words imported into the English language do intrigue me. A "Plumber" is a worker of lead, about the only Plumber today tunes organs, it seems lead replacements alter the tone.

Every trade has them, electrical trade it is the "Lamp" "Bulb" and "Tube" although clearly the lamp refers to the whole unit, and it could have a mantel, wick or bulb inside, we see so-called electricians trying to tell people what the items are called, and the regulations don't help with references to "Lighting fittings using filament lamps" going back to the 13th edition.

Bulb refers to the shape, as does cylinder with pipe fitting trade. But most of the words we use, have a wider use, transformer

is a good example, in the electrical trade we think of a wire wound device, but these have been replaced with electronic devices which not old transform the voltage but also the frequency, and it leaves us with a problem, as the electronic version often will not work with LED lights.

So however much we think it is the wrong name, we have forced to use the name given to it by manufacturers and suppliers

as otherwise we get the wrong thing. I remember wanting a head lamp bulb, so ordered a head lamp, and got all but the bulb. The buzz word today seems to be combi

and Hybrid. And they can mean such a different thing, Hybrid with 2 wheels means on and off-road, with 4 wheels it has electric and liquid fuels. Samuel Johnson must be turning in his grave!
I think this tank has a hole in it

? But I am a bit of a butcher, I would bend the float bar so less water in the tank, until "Plumber" arrives to do a proper fix.

 

[HERTS P&D]

Yes, a lot of amateurs get it wrong.

Google Search

Andy

 

[ChrisJP]

I've always thought the the description "cistern" was restricted to the tank providing toilet flushing. Any other tank with a float valve in it is a "cold water storage tank" or a "feed and expansion tank". This seems to me to a be a useful distinction but, hey-ho, if the purists insist they are all called "cisterns", who am I to argue?

 

[Johntheo5]

I've only installed one cold water storage tank/cistern and that was to replace a steel one in my own house when I converted my attic into a bedroom, neither had a lid and still doesn't, the plastic one I bought certainly didn't come with a lid, is this normal???, if so, then until the plumber or house owner makes or buys one can you call it a CWST??

 

[Madrab]

I was always told that the difference between a tank and cistern is -

a cistern is a container for liquid, should have a removable lid, is typically open to the atmosphere and is filled by a source whose level is controlled internally by a valve and overflow.

A tank is a sealed container for liquids or gases that is typically filled externally.