Chris Hogg wrote:
On 10 Oct 2019 15:18:51 GMT, Tim+ wrote:

Harry Bloomfield, Esq. wrote:
Tim+ has brought this to us :
Long term answer may be to just go back to external H & C taps but he does
like the pre-mixed warm water.

Any suggestions?

What is the height of the header tank, above the tap?

1960s two storey house, header in the loft. All very conventional. The
pressure should be right range for the valve and when it’s working, it
works fine. It just seems to be the non-return valves causing issues.


So remove and eviscerate them, then replace them. Who's to know?


The homeowner would when his loft header tank overflows. The fact that one
seems to be getting jammed, probably due to mains pressure cold water,
suggests that without it back-flow through the HW system would occur.

Tim

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