C Heating control

[jon]

Had a Power failure in my street on Thursday due to an underground cable fault and of course all electric clocks in house stopped apart from the clock in the CH control.Power was off 4-5 hours so can someone please tell me why this clock managed to keep its time,no batteries in it that I know of.Im very leased to know that it does keep going but would also like to know how. Thanks

jon

[Palindrome]

Depends on the age and technology.

Older, mechanical, timeswitches use an electrically-wound mainspring. Newer, electronic ones have a cell or two on the printed circuit board. Some have an ultra low power clock chip that is read by the main clock on restoration of power.

[jon]

Thanks Sue.I have since found instruction for control,a Danfoss.It does mention a battery and that if power is off over two midnights all settings will be lost and that it must be reset to factory settings using a sharp object such as a match

jon