i know this question may sound strange but on the side off the clock timer there is a little black switch ..off on constant or timed ..which one is recommended when you have set the timer and you want your heating to come on at these prefered times thankyou
OFF will mean always off - never on... ignoring the timer
ON will mean always on - never off... also ignoring the timer
TIMED will mean on and off according to the timer settings
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