"Doctor Drivel" wrote:

A CM67 with optimisation will work very well with a system with gravity DHW.
You need to understand how it works and the also the CM67.

It is a well known drawback of the CM67 that it is not a one box
controller solution if timed hot water is required as there is a total
absence of a second timer in all the CM6* series.

The second box commonly used is unfortunately one of the clunky 6000
series controllers like the ST6100A but that can be hidden out of the
way. :-)

You'd better read the manual again Dribble!

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