Cold Water Tank in loft - constant drip from ball valve

18 Oct 2009
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United Kingdom

I've just noticed that my cold water tank in the loft has a contant drip like the ball valve does not turn off completely. There is nothing coming out of the overflow.

A colleague has told me that I may have a leak somewhere as because the tank is not filling the water must be going somewhere. Or do I just need a new ball valve?

Many thanks

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It takes a long, long time for the ball valve to completely stop the flow, especially on the larger tanks.
Try lifting the ball up yourself and see if it stops flowing then. If it doesn't, then you need a new valve or simply a new washer inside it.
If its heavily limescaled up though, I personally wouldn't bother trying to undo it.
As the level doesn't get anywhere near the overflow, there's no need to panic about its immediate attention.
John :)
Thanks John

It is a pretty large tank although I'm not sure it actually ever actually stops dripping. I went out yesterday for five hours and there was still a fair drip when I got home. Nothing was using water indoors. I checked the loos, taps etc.

I will pop up and take a look to see if it stops when I lift it up. Can I relax on the leak front then?

Best wishes
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If its a large tank, its likely to be the one that replenishes the domestic hot water supply.....therefore its level will be constantly altering as you use water.
Only if you are away for days and the level rises should you worry!
John :)

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