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I have a question / seeking advice about my CWS tanks.

I have 2 CWS tanks in the loft both are connected at the bottom of the tanks.

The first tank has the CW supply regulated by a ball & stopcock, but no overflow pipe.

The second tank of the same size has the overflow pipe but no ball & stopcock.

My query is should the first tank have a overflow pipe as well? or is it regulated by the water pressure from the second tank, so if the stop cock fails in the first tank, will the water level rise as well in the 2nd tank and out through the overflow pipe? (should of paid more attention in physics class). TIA.

Hi handoverfist,

So long as the 2 tanks are connected the water should never rise, in either tank, higher than the over flow.

Sounds like a cylinder has been fitted that required a larger volume tank, and instead of buying a new larger tank, they have just tagged a new one to it.

If your water system is running and there are no signs of damp under the tanks I'd say you should be fine.

Hope this helps