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What is a programmer?
... an explanation for householders.
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
diff erent 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.
The text below has been edited and approved by the Plain
English Campaign, who has issued a Crystal Mark to be
displayed with it.
W
h
a
t is a pr
ogr
ammer?
Please note: A timeswitch is a single channel programmer. It will
allow you to set your system’s On and Off periods.
