Operation Manual
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... schedules 9 Program schedule overrides 12 Auto Changeover 14 Built-in compressor protection 16 Smart Response® Technology 18 RTH6400 Programmable Thermostat Appendices Battery installation 18 Customer assistance 19 In case of difficulty 20 Limited warranty 22 This thermostat is pre-programmed and ready to go ! See page 3 to check settings. 1 69-2211EF-05
... schedules 9 Program schedule overrides 12 Auto Changeover 14 Built-in compressor protection 16 Smart Response® Technology 18 RTH6400 Programmable Thermostat Appendices Battery installation 18 Customer assistance 19 In case of difficulty 20 Limited warranty 22 This thermostat is pre-programmed and ready to go ! See page 3 to check settings. 1 69-2211EF-05
Operation Manual
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... on the purchase of reliable service and easy-to read - It has been designed to give you many years of your new Honeywell thermostat. Features • Separately programmable weekday, Saturday, and Sunday schedules. • One-touch temp control overrides program schedule at any time. • Large, clear, backlit display is easy to -use...
... on the purchase of reliable service and easy-to read - It has been designed to give you many years of your new Honeywell thermostat. Features • Separately programmable weekday, Saturday, and Sunday schedules. • One-touch temp control overrides program schedule at any time. • Large, clear, backlit display is easy to -use...
Operation Manual
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RTH6400 Programmable Thermostat This thermostat is set the time and day. All you wake at 6 am, leave at 8 am, return at 6 pm and go . Select system setting (Heat/Cool): Preset ...): Preset to bed at any time, and manually adjust the temperature (see page 7 3. Set time and day (required for proper operation See page 6 2. Your new thermostat is pre-programmed and ready to go to Auto To change if needed: 1.
RTH6400 Programmable Thermostat This thermostat is set the time and day. All you wake at 6 am, leave at 8 am, return at 6 pm and go . Select system setting (Heat/Cool): Preset ...): Preset to bed at any time, and manually adjust the temperature (see page 7 3. Set time and day (required for proper operation See page 6 2. Your new thermostat is pre-programmed and ready to go to Auto To change if needed: 1.
Operation Manual
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RTH6400 Programmable Thermostat Quick reference to display screen Current inside temperature Low battery warning (see page 15) Current time/day (see page 6) Smart Response® technology in effect (...
RTH6400 Programmable Thermostat Quick reference to display screen Current inside temperature Low battery warning (see page 15) Current time/day (see page 6) Smart Response® technology in effect (...
Operation Manual
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Press DONE to select the day of the week. 3. Note: If the display flashes Set Clock, the thermostat will follow your settings for the weekday "Wake" time period until you reset the time and day. Press the SET DAY button, then press s or t ...
Press DONE to select the day of the week. 3. Note: If the display flashes Set Clock, the thermostat will follow your settings for the weekday "Wake" time period until you reset the time and day. Press the SET DAY button, then press s or t ...
Operation Manual
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In "Auto" mode (the most commonly used setting), the fan runs only when the heating or cooling system is on. Select the fan setting Set Clock/Day/ Schedule Fan Auto System Heat M28405 Set Clock/Day/ Schedule Fan System On Heat M28406 RTH6400 Programmable Thermostat Press the FAN button to "On," the fan runs continuously. 7 69-2211EF-05 If set to select Auto or On.
In "Auto" mode (the most commonly used setting), the fan runs only when the heating or cooling system is on. Select the fan setting Set Clock/Day/ Schedule Fan Auto System Heat M28405 Set Clock/Day/ Schedule Fan System On Heat M28406 RTH6400 Programmable Thermostat Press the FAN button to "On," the fan runs continuously. 7 69-2211EF-05 If set to select Auto or On.
Operation Manual
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...-2211EF-05 Press the SYSTEM button to select Heat, Cool or Off. • Heat: Thermostat controls only the heating system. • Cool: Thermostat controls only the cooling system. • Off: Heating and cooling systems are off. • Auto: Thermostat automatically selects heating or cooling depending on the indoor temperature. To prevent possible compressor...
...-2211EF-05 Press the SYSTEM button to select Heat, Cool or Off. • Heat: Thermostat controls only the heating system. • Cool: Thermostat controls only the cooling system. • Off: Heating and cooling systems are off. • Auto: Thermostat automatically selects heating or cooling depending on the indoor temperature. To prevent possible compressor...
Operation Manual
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...temperature you leave for the day. RETURN 6:00 pm 70 ° Set to the time you return home and the temperature you want during the morning, until bedtime. RTH6400 Programmable Thermostat Save money by setting program schedules It's easy to program your system for weekdays, Saturday and Sunday. ...WAKE 6:00 am 62 ° Set to the time you leave home and the temperature you want while you want during ...
...temperature you leave for the day. RETURN 6:00 pm 70 ° Set to the time you return home and the temperature you want during the morning, until bedtime. RTH6400 Programmable Thermostat Save money by setting program schedules It's easy to program your system for weekdays, Saturday and Sunday. ...WAKE 6:00 am 62 ° Set to the time you leave home and the temperature you want while you want during ...
Operation Manual
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... can reduce your heating/cooling expenses. (See next page to use energy saving program settings. Operating Manual Energy saving settings for maximum cost savings This thermostat is pre-set to adjust times and temperatures of each time period.) Wake (6:00 am) Leave (8:00 am) Return (6:00 pm) Sleep (10:00 pm...
... can reduce your heating/cooling expenses. (See next page to use energy saving program settings. Operating Manual Energy saving settings for maximum cost savings This thermostat is pre-set to adjust times and temperatures of each time period.) Wake (6:00 am) Leave (8:00 am) Return (6:00 pm) Sleep (10:00 pm...
Operation Manual
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RTH6400 Programmable Thermostat To adjust program schedules Set Clock/Day/ Schedule Fan Auto System Heat Done Set Day Set Schedule 8:00 Set Schedule AM Heat Setting 62 Leave ... to set Saturday time periods. 6. Note: You can press CANCEL PERIOD to save & exit. Press NEXT to program (Heat or Cool). Note: Make sure the thermostat is set to the system you want to set Sunday time periods, then press DONE to eliminate unwanted time periods (except Wake). 11 69-2211EF...
RTH6400 Programmable Thermostat To adjust program schedules Set Clock/Day/ Schedule Fan Auto System Heat Done Set Day Set Schedule 8:00 Set Schedule AM Heat Setting 62 Leave ... to set Saturday time periods. 6. Note: You can press CANCEL PERIOD to save & exit. Press NEXT to program (Heat or Cool). Note: Make sure the thermostat is set to the system you want to set Sunday time periods, then press DONE to eliminate unwanted time periods (except Wake). 11 69-2211EF...
Operation Manual
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... Heat Setting 75 6:30AM Run Schedule Fan Auto System Heat M28410 Press s or t to cancel temporary setting and resume program schedule. Note: Make sure the thermostat is set to the system you leave for the current time period. To cancel the temporary setting at any time, press RUN SCHEDULE. 69-2211EF...
... Heat Setting 75 6:30AM Run Schedule Fan Auto System Heat M28410 Press s or t to cancel temporary setting and resume program schedule. Note: Make sure the thermostat is set to the system you leave for the current time period. To cancel the temporary setting at any time, press RUN SCHEDULE. 69-2211EF...
Operation Manual
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..."Hold" and resume the programmed schedule. 13 69-2211EF-05 M28411 Whatever temperature you set to the system you want to adjust the thermostat manually, as needed. RTH6400 Programmable Thermostat Program schedule override (permanent) Press to permanently adjust temperature. 69 75 Inside Heat Hold Setting 6:30AM Run Schedule Fan Auto System Heat .... Press to permanently adjust the temperature. This will be maintained 24 hours a day until you to control (heat or cool). Note: Make sure the thermostat is set will override the temperature settings for all time periods.
..."Hold" and resume the programmed schedule. 13 69-2211EF-05 M28411 Whatever temperature you set to the system you want to adjust the thermostat manually, as needed. RTH6400 Programmable Thermostat Program schedule override (permanent) Press to permanently adjust temperature. 69 75 Inside Heat Hold Setting 6:30AM Run Schedule Fan Auto System Heat .... Press to permanently adjust the temperature. This will be maintained 24 hours a day until you to control (heat or cool). Note: Make sure the thermostat is set will override the temperature settings for all time periods.
Operation Manual
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Press the Select Heat/Cool button to select between the cool and heat settings. When the system mode is in Auto, the thermostat automatically selects heating or cooling depending on the same day. For example, if the heat temperature is raising the cool setting up to view/adjust... on the indoor temperature. While in the Auto mode, if a schedule override takes place (temporarily or permanently) the thermostat will show an up arrow next to "cool" to show the thermostat is raised to where it gets within 3-dgrees of the cool setting, the display will automatically adjust the cooling and...
Press the Select Heat/Cool button to select between the cool and heat settings. When the system mode is in Auto, the thermostat automatically selects heating or cooling depending on the same day. For example, if the heat temperature is raising the cool setting up to view/adjust... on the indoor temperature. While in the Auto mode, if a schedule override takes place (temporarily or permanently) the thermostat will show an up arrow next to "cool" to show the thermostat is raised to where it gets within 3-dgrees of the cool setting, the display will automatically adjust the cooling and...
Operation Manual
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Auto Changeover RTH6400 Programmable Thermostat If the cool temperature is lowered to where it gets close to the heat setting, an arrow next to heat will show the thermostat is increasing to maintain 3 degrees between heat and cool settings. CAUTION: To avoid possible compressor damage, do not use Auto Changeover if the outside temperature...
Auto Changeover RTH6400 Programmable Thermostat If the cool temperature is lowered to where it gets close to the heat setting, an arrow next to heat will show the thermostat is increasing to maintain 3 degrees between heat and cool settings. CAUTION: To avoid possible compressor damage, do not use Auto Changeover if the outside temperature...
Operation Manual
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..."In Recovery" is displayed when the system is reached at the time you wake at 6. Smart Response® Technology: This feature allows the thermostat to "learn" how long the furnace and air conditioner take to reach programmed temperature settings, so the temperature is activated before 6 am , ...time to 70°. The heat will come on before a scheduled time period. 17 69-2211EF-05 Smart Response® Technology RTH6400 Programmable Thermostat Inside 75 6:38 In Recovery AM Cool Setting 75 Set Clock/Day/ Schedule Fan Auto Cool On System Cool M27476 Displays when Smart Response...
..."In Recovery" is displayed when the system is reached at the time you wake at 6. Smart Response® Technology: This feature allows the thermostat to "learn" how long the furnace and air conditioner take to reach programmed temperature settings, so the temperature is activated before 6 am , ...time to 70°. The heat will come on before a scheduled time period. 17 69-2211EF-05 Smart Response® Technology RTH6400 Programmable Thermostat Inside 75 6:38 In Recovery AM Cool Setting 75 Set Clock/Day/ Schedule Fan Auto Cool On System Cool M27476 Displays when Smart Response...
Operation Manual
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... No. 50002883-001 *Use to cover marks left by old thermostats. 19 69-2211EF-05 Or call Honeywell Customer Care tollfree at 1-800-468-1502. Accessories/replacement parts To order, please call Honeywell Customer Care toll-free at 1-800-468-1502. ACubsotuotmyeorurasnseiwstathnecremostat RTH6400 Programmable Thermostat M28415 Model number xxxxxxx Date code xxxxxxx M28416 For assistance...
... No. 50002883-001 *Use to cover marks left by old thermostats. 19 69-2211EF-05 Or call Honeywell Customer Care tollfree at 1-800-468-1502. Accessories/replacement parts To order, please call Honeywell Customer Care toll-free at 1-800-468-1502. ACubsotuotmyeorurasnseiwstathnecremostat RTH6400 Programmable Thermostat M28415 Model number xxxxxxx Date code xxxxxxx M28416 For assistance...
Operation Manual
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Most problems can be corrected quickly and easily. Temperature settings do not change Make sure heating and cooling temperatures are correctly installed (see page 15). Operating Manual In case of difficulty If you have difficulty with your thermostat, please try the following suggestions. Display is blank • Make sure fresh AA alkaline batteries are set to acceptable ranges: • Heat: 40° to 90°F (4.5° to 32°C). • Cool: 50° to 99°F (10° to 37°C). 69-2211EF-05 20
Most problems can be corrected quickly and easily. Temperature settings do not change Make sure heating and cooling temperatures are correctly installed (see page 15). Operating Manual In case of difficulty If you have difficulty with your thermostat, please try the following suggestions. Display is blank • Make sure fresh AA alkaline batteries are set to acceptable ranges: • Heat: 40° to 90°F (4.5° to 32°C). • Cool: 50° to 99°F (10° to 37°C). 69-2211EF-05 20
Operation Manual
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...furnace door is closed securely. • Wait 5 minutes for the system to restart safely, without damage to respond. In case of Difficulty section in your thermostat Installation Guide. 21 69-2211EF-05 "Cool On" or "Heat On" is flashing • Compressor protection feature is system does not set system to Heat... temperature is set system to Cool. Other problems • If the above measures do not resolve the problem, check the In Case of difficulty RTH6400 Programmable Thermostat Heating or cooling • Press SYSTEM button to set lower than the Inside temperature.
...furnace door is closed securely. • Wait 5 minutes for the system to restart safely, without damage to respond. In case of Difficulty section in your thermostat Installation Guide. 21 69-2211EF-05 "Cool On" or "Heat On" is flashing • Compressor protection feature is system does not set system to Heat... temperature is set system to Cool. Other problems • If the above measures do not resolve the problem, check the In Case of difficulty RTH6400 Programmable Thermostat Heating or cooling • Press SYSTEM button to set lower than the Inside temperature.
Operation Manual
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..., INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, IS HEREBY LIMITED TO THE ONE-YEAR DURATION OF THIS WARRANTY. 1-year limited warranty RTH6400 Programmable Thermostat THIS WARRANTY IS THE ONLY EXPRESS WARRANTY HONEYWELL MAKES ON THIS PRODUCT.
..., INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, IS HEREBY LIMITED TO THE ONE-YEAR DURATION OF THIS WARRANTY. 1-year limited warranty RTH6400 Programmable Thermostat THIS WARRANTY IS THE ONLY EXPRESS WARRANTY HONEYWELL MAKES ON THIS PRODUCT.