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What is a programmer?
Programmers allow you to set ’On’ and ’Off’ time periods� Some models switch the central heating and
domestic hot water on and off at the same time, while others allow the domestic hot water and heating
to come on and go off at different times�
Set the ’On’ and ’Off’ time periods to suit your own lifestyle� On some programmers you must also set
whether you want the heating and hot water to run continuously, run under the chosen ’On’ and ’Off’
heating periods, or be permanently off�
The time on the programmer must be correct� Some types have to be adjusted in spring and autumn at
the changes between Greenwich Mean Time and British Summer Time�
You may be able to temporarily adjust the heating programme, for example, ’Override’, ’Advance’ or
’Boost’� These are explained in the manufacturer`s instructions�
The heating will not work if the room thermostat has switched the heating off� And, if you have a hot
water cylinder, the water heating will not work if the cylinder thermostat detects that the hot water has
reached the correct temperature�
