RTH6400 Programmable Thermostat
1 69-2211EF—05
About your new thermostat
This thermostat is ready to go!
Your new thermostat is pre-programmed
and ready to go.
See page 3 to check settings.
Table of contents
About your new thermostat
Thermostat features .................................... 2
Programming at a glance ............................3
Quick reference to controls ......................... 4
Quick reference to display ...........................5
Programming & Operation
Set time and day ......................................... 6
Select fan setting (auto/on) ........................ 7
Select system setting (heat/cool) ................ 8
Using program schedules ...........................9
Program schedule overrides ..................... 12
Auto Changeover ......................................14
Built-in compressor protection ..................16
Smart Response
®
Technology ................... 18
Appendices
Battery installation ..................................... 18
Customer assistance ................................19
In case of difficulty ....................................20
Limited warranty ........................................22