In an earlier contribution to this discussion,
Doctor Drivel wrote:


It will be better if you split the system up into two zones. Say,
upstairs and downstairs, and have a pump and non-return valve on
each. Grundfos do twin pumps sets for this. Then you divide the
system up. You can also have each zone on separate temperature stats
and timers. Upstairs can be off during the day and only on during
bedtime and in the mornings. This is the best approach as it solves
the problem and saves on fuel bills.

Perhaps I should emphasise that having twin pumps isn't a pre-requisite for
zoning. It is perfectly feasible - indeed more common than not - to have a
single pump for multiple zones. After all, you're only going to have one
boiler - or *are* you?!!!
--
Cheers,
Set Square
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