In article ,
David P wrote:
My own hot water tank is in the roofspace and it gets a feed from the
rising water main to the house and the tank has a tight fitting cover.

However the cold water tank in my roofspace is much older and had a
damaged top and I can see the base of the tank is full of crud.

It seems that I am nrushing my teeth using water from the worse one !!!

This must be true in millions of households. Many have a heating system
like mine with hot & cold tanks in their roofspace plus a hot water
cylinder. {1}. And maybe they too have their cold water in the bathroom
supplied from their tank in the roofspace.

I've never seen an installation in a house with separate header tanks for
hot and cold.

The bathroom basin should be really be fed with mains cold water, though.
Baths and showers off the header tank to get adequate flow.

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*Just give me chocolate and nobody gets hurt

Dave Plowman London SW
To e-mail, change noise into sound.