On 21/10/2019 19:53, ARW wrote:
I have never heard of it before.

I just turn it on when it's cold and the date has nothing to do with it.

Ours runs each day to heat the hot water tank all year and each room has
its own motorised valve and timer/stat. If it is cold, one or more rooms
will come on, otherwise they won't. Why would I want to turn it off and
on at certain times of the year?

SteveW