DHW and Expansion tanks - why not one tank?

[kitehigh]

Hello, is there a reason why the DHW and CH/boiler expansion tanks cannot be one tank in a fully pumped, indirect system?

I.e. one tank with cold feed splitting to CH and DHW cylinder and vents back to same tank:

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• kitehigh
• 22 Aug 2013
• 1

 

[Agile]

Very simply because the F&E tank is an expansion tank and you cannot let heating system water mix with domestic water.

Tony