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User Instructions
GB
Optimum start control (OSC)
Your thermostat includes an optional optimum start control. This feature 
allows you to set the time at which you require a room temperature by. 
The thermostat then calculates how soon before the event time the 
system must be turned up to ensure that the room is at the temperature 
by the required time. A full description of this and how to enable it and 
set it up is given in User Advanced Programming, steps 12 & 13, (page 
28). When this function is active, the set temperature will  ash on the 
display
Battery replacement (battery models only)
When batteries are low a battery symbol will 
appear on the display. You have 15 days to replace 
the batteries before the unit shuts down. When 
replacing batteries ensure that only high quality 
alkaline cells are use.
IMPORTANT: After replacing the batteries press and release the RESET 
button to restart the unit. All date, time, programming and override 
settings are maintained for the life of the product.
User Advanced 
Programming Options
Important: The thermostat has been set in the factory to suit most 
situations, however, there are additional optional settings which can 
improve the comfort, convenience and energy e ectiveness of your 
thermostat. These are set in the User Advanced Programming and  
Installer Advanced Programming modes.