You Have A Power Outage; You Have A System Error Message - Carrier Thermostat Homeowner's Manual

WHAT IF...

You have a power outage...

An internal power source maintains the
desired temperature settings
indefinitely.

You have a system error message...

The temperature sensor failure indicator
sends a -- reading to the LCD display.
This means your thermostat's
temperature sensor is no longer able to
measure temperatures. You will need to
contact your dealer to repair the
problem.
An E2 reading on the LCD display
means there is not enough voltage for
the system to operate. Contact your
dealer for further information.
A flashing E3 (alternating with room
temperature) indicates the outdoor air
temperature sensor is absent or not
working properly (and is needed for
proper operation).
If the outdoor air temperature sensor is
absent, the outdoor temperature
reading will be --.
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