Operation – ALL MODELS
Select fan setting (ON/AUTO/CIRC)
Press 
to select:
ON: Fan runs continuously. Use this mode for maximum air circulation/air cleaning.
AUTO: Fan runs only when the heating or cooling system is on.
CIRC: Same as AUTO, but if the fan has been off for 20 minutes the fan will be activated for a 10 minute cycle. Use this mode for a balance of energy savings and air circulation/cleaning.
Reset service reminder messages
Press and hold 
and 
together for three seconds to reset a service reminder message.
Battery installation and reset button
RESET
BUTTON
The thermostat can either be AC or battery powered, or both. When wired to be AC powered, the batteries are optional and only provide backup power to the clock.
The thermostat has a memory backup that saves the thermostat’s settings in case of a power interruption.
The reset button located under the battery cover can be used to reset the thermostat back to factory defaults.
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61000651B 8400 Tstat Owners.indd 7 | 7/23/09 10:43:03 AM |