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THERMOSTAT OPERATION FEATURES
Clock
Without batteries the clock will continue to operate for 8 hours after power is
removed. With batteries, the clock operates until the end of the battery life.
Batteries
If installed without a common (C) wire, two alkaline AA batteries are required
for operation. The thermostat is designed to operate up to one year on a set
of batteries. A battery indicator on the display warns when battery
replacement is needed. See Owner’s Manual for details.
If installed with a Common (C) wire and batteries, the thermostat will use
batteries only when 24VAC power is not present. The changeover between
24VAC power and battery power is automatic.
Display Lighting
The display has two levels of lighting, high level and low level. High level
lighting comes on for 10 seconds when the door is opened and/or buttons are
being pressed when installed with a Common (C) wire or with batteries.
Low level lighting is only available if the thermostat is installed with a Common
(C) wire. It is not available with batteries. The low level can be selected (see
Configuration Option 18) for continuous backlight.
Door Switch
When the door is opened, the display changes from its normal operation view.
The large temperature display disappears so it will be available for other
functions. If the door is left open for 3 minutes, the display reverts to normal
operation.