Honeywell RTH7400 Wifi Thermostat User Manual
Included in your box
Tools you will need
Tools you may need
Removing your old thermostat
- Turn the power OFF. To protect yourself and your equipment, Turn off the power at the breaker box or switch that controls your heating/cooling system.
- Check that your system is off. Change the temperature on your old thermostat. If you don’t hear the system turn on within 5 minutes, the power is off.
Note: If you have a digital thermostat that has a blank display, skip this step. - Remove the old thermostat’s faceplate. On most thermostats, you can take off the faceplate by grasping and gently pulling. Some thermostats may have screws, buttons, or clasps. Do not remove any wires from your thermostat at this time!
- Make sure there are no 120/240V wires. Do you have thick black wires with wire nuts? Is your thermostat 120V or higher? If you answered yes to either of these questions, you have a line voltage system and the thermostat will not work. If you are unsure visit: honeywellhome.com/support
- Take a picture of how your wiring looks right now. Be sure to include the letters next to the terminals where the wires are inserted. This will be a helpful reference when wiring your thermostat. Tip: If the color of your wires has faded or if 2 terminals have the same wire color, use the wire labels provided in the package to label each wire.
- Disconnect the wires and remove the old wall plate. Use a screwdriver to release wires from terminals. Then, use a wire label to identify each wire as it’s disconnected. The letter on the wire label should match the letter on the terminal. Tip: To prevent wires from falling back into the wall, wrap the wires around a pencil.
Key features
System Setup options
| Number | Description | Options (factory default in bold) |
|
120 |
Scheduling Options | 0 = Non-Programmable 1 = 1-Week Programmable 2 = 5-2 Programmable 3 = 5-1-1 Programmable 4 = 7-Day Programmable Note: You can change the default HTTPS://www.manua.ls/honeywell/rth8500d/manual MO–FR, SA–SU schedule here. To edit periods during days, temperature setpoints, or to turn Schedule On/Off, touch MENU and go to SCHEDULE. |
| 125 | Temperature Indication Scale | 0 = Fahrenheit 1 = Celsius |
|
200 |
Heating System Type | 1 = Conventional Forced Air Heat 2 = Heat Pump 3 = Radiant Heat (Boiler) 5 = None (Cool Only) Note: This option selects the basic system type your thermostat will control. |
|
205 |
Heating Equipment Type | Conventional Forced Air Heat: 1 = Standard Efficiency Gas Forced Air 2 = High Efficiency Gas Forced Air 3 = Oil Forced Air 4 = Electric Forced Air 5 = Hot Water Fan Coil Heat Pump: 7 = Air to Air Heat Pump 8 = Geothermal Radiant Heat: 9 = Hot Water Radiant Heat 12 = Steam Note: This option selects the equipment type your thermostat will control. Note: This feature is NOT displayed if feature 200 is set to Cool Only. |
| 218 | Reversing Valve O/B | 0 = O (O/B in Cool) 1 = B (O/B in Heat) Note: This option is only displayed if the Heat Pump configured. Select whether reversing valve O/B should energize in cool or in heat. |
| 220 | Cool Stages / Compressor Stages 200=Conv / 200=HP | 0, 1, 2 Note: Select how many Cool or Compressor stages of your equipment the thermostat will control. Maximum of 2 Cool/Compressor Stages. Set value to 0 if you do not have Cool Stage/ Compressor Stage. |
|
221 | Heat Stages / Backup Heat Stages Heat Stages | Heat Stages: 1, 2 Backup Heat Stages: 0, 1 Note: Select how many Heat or Aux/E stages of your equipment the thermostat will control. Maximum of 2 Heat Stages for conventional systems. Maximum of 1 Aux/E stage for systems with more than 1 heating equipment type. Set value to 0 if you do not have Heat Stage/Backup Heat Stage. |
| 230 | Fan Control | 1 = Equipment 2 = Thermostat Note: This ISU is only displayed if ISU 205 is set to Electric Forced Air or Fan Coil. |
|
300 |
System Changeover | 0 = Manual 1 = Automatic Note: The thermostat can automatically control both heating and cooling to maintain the desired indoor temperature. To be able to select “automatic” system mode on thermostat home screen, turn this feature ON. Turn it OFF if you want to control heating or cooling manually. |
|
303 |
Auto Differential | 0 °F to 5 °F or 0.0 °C to 2.5 °C Note: Differential is the minimum number of degrees rise or fall required during off cycle to switch from the last active mode (heat or cool) to the opposite mode when the thermostat is in auto-changeover. The differential is NOT deadband. The deadband temperature between when heating (or cooling) cycles on and cycles off to maintain setpoint is not adjustable. Honeywell uses an algorithm that fixes deadband at 0 °F. |
| Number | Description | Options (factory default in bold) |
|
365 |
Cool 1 CPH (Cooling cycle rate stage 1) | 1 – 6 CPH (3 CPH) Note: This ISU is only displayed when Cool /Compressor Stages is set to 1 or more stages. Cycle rate limits the maximum number of times the system can cycle in a 1 hour period measured at a 50% load. For example, when set to 3 CPH, at a 50% load, the most the system will cycle is 3 times per hour (10 minutes on, 10 minutes off). The system cycles less often when load conditions are less than or greater than a 50% load. |
| 366 | Cool 2 CPH (Cooling cycle rate stage 2) | 1 – 6 CPH (3 CPH) Note: This ISU is only displayed when Cool /Compressor Stages is set to 2. |
|
370 |
Heat 1 CPH (Heating cycle rate stage 1) | 1 – 12 CPH Note: This ISU is only displayed when Heat Stages is set to 1 stage or more stages. Cycle rate limits the maximum number of times the system can cycle in a 1 hour period measured at a 50% load. For example, when set to 3 CPH, at a 50% load, the most the system will cycle is 3 times per hour (10 minutes on, 10 minutes off). The system cycles less often when load conditions are less than or greater than a 50% load. The recommended (default) cycle rate settings are below for each heating equipment type: Standard Efficiency Gas Forced Air = 5 CPH; High Efficiency Gas Forced Air = 3 CPH; Oil Forced Air = 5 CPH; Electric Forced Air = 9 CPH; Fan Coil = 3 CPH; Hot Water Radiant Heat = 3 CPH; Steam = 1 CPH. |
|
371 |
Heat 2 CPH (Heating cycle rate stage 2) | 1 – 12 CPH Note: This ISU is only displayed when Heat Stages is set to 2 stages. The recommended (default) cycle rate settings are below for each heating equipment type: Standard Efficiency Gas Forced Air = 5 CPH; High Efficiency Gas Forced Air = 3 CPH; Oil Forced Air = 5 CPH; Electric Forced Air = 9 CPH; Fan Coil = 3 CPH; Hot Water Radiant Heat = 3 CPH; Steam = 1 CPH. |
|
375 | Aux Heat CPH (Heating cycle rate Auxiliary Heat) | 1 – 12 CPH Note: This ISU is only displayed when ISU 200 = Heat Pump and ISU 221=1. It is only displayed when Auxiliary Heat is configured. The recommended cycle rate settings are below for each heating equipment type: Standard Efficiency Gas Forced Air = 5 CPH; High-Efficiency Gas Forced Air = 3 CPH; Oil Forced Air = 5 CPH; Electric Forced Air = 9 CPH. |
| 425 | Smart Response | 0 = No 1 = Yes Note: Smart Response is a comfort setting. Heat or Cooling equipment will turn on earlier, ensuring the indoor temperature will match the setpoint at the scheduled time. See page 16. |
| 430 | Minimum Cool Temperature Setpoint | 50 °F to 99 °F (50 °F) 10.0 °C to 37.0 °C (10.0 °C) Note: The cool temperature cannot be set below this level. |
| 431 | Maximum Heat Temperature Setpoint | 40 °F to 90 °F (90 °F) 4.5 °C to 32.0 °C (32.0 °C) Note: The heat temperature cannot be set above this level. |
| 702 | Air Filters | 0 – 1 Note: This ISU refers to the number of air filters in the system. |
|
711 |
Air Filter 1 Replacement Reminder | 0 = Off 10 = 45 Calendar Days 1 = 10 Run Time Days 11 = 60 Calendar Days 2 = 20 Run Time Days 12 = 75 Calendar Days 3 = 30 Run Time Days 13 = 3 Calendar Months 4 = 45 Run Time Days 14 = 4 Calendar Months 5 = 60 Run Time Days 15 = 5 Calendar Months 6 = 90 Run Time Days 16 = 6 Calendar Months 7 = 120 Run Time Days 17 = 9 Calendar Months 8 = 150 Run Time Days 18 = 12 Calendar Months 9 = 30 Calendar Days 19 = 15 Calendar Months Note: Set a reminder for when to change your air filter. Choose either calendar or equipment run time-based reminder. |
| 1401 | Idle Brightness | 0= Off, 0 – 5 Note: Adjust the brightness of an inactive backlight (idle screen) from default 0 (backlight off) to 5 (maximum brightness). Common wire required for settings 1–5. |
| 1410 | Clock Format | 12 hour, 24 hour |
| 1415 | Daylight saving time | 0 = Off 1 = On Note: Set to Off in areas that do not follow Daylight Saving Time. |
NOTE:
Once you have cycled through all of the System Setup numbers, Done is displayed. Press Select to save and exit.
System operation settings
- Press the Mode button to cycle to the next available System mode.
- Cycle through the modes until the required System mode is displayed and leave it to activate.
NOTE: Available System modes vary by model and system settings.
System modes:
- Auto: The thermostat selects heating or cooling as needed.
- Heat: The thermostat controls only the heating system.
- Cool: The thermostat controls only the cooling system.
- Em Heat (only for heat pumps with auxiliary heat): The thermostat controls Auxiliary Heat. A compressor is not used.
- Off The heating and cooling system is off. The fan will still operate if a fan is set to On or Circulate.
Program Schedule
You can program four time periods each day, with different settings for weekdays and weekends. We recommend the pre-set settings (shown in the table below) since they can reduce your heating/cooling expenses. Wake – Set the time you wake up and the temperature you want during the morning, until you leave for the day.
Away – Set to the time you leave home and the temperature you want while you are away (usually an energy-saving level). Home – Set to the time you return home and the temperature you want during the evening, until bedtime. Sleep – Set to the time you go to bed and the temperature you want overnight (usually an energy-saving level).
Wiring—conventional systems
Alternate wiring (conventional systems)
If labels do not match terminals, connect wires as shown below (see notes, below). NOTES:
- If you must connect both R and Rc wires, set the R Slider Tab to the down position (2 wires).
- If your old thermostat had both R and RH wires, set the R Slider Tab to the down position (2 wires). Then connect the R wire to the Rc terminal, and the RH wire to the R terminal.
- If your old thermostat had only 1 C or C1 wire, connect it to the C terminal. If your old thermostat had 2 C or C1 wires, wrap each separately with electrical tape and do not connect them.
Connect wires: heat pump
- Match each labeled wire with the same letter on the new thermostat.
- Insert the wires into the matching terminal. NOTE: If you have difficulty inserting wires, you may have to press the terminal push button next to the corresponding terminal. Labels don’t match? If labels do not match the letters on the thermostat, see “Alternate wiring (for heat pumps only)” below.
Alternate wiring (for heat pumps only)
NOTES:
- Keep R Slider Tab in the up position (1 wire).
- If your old thermostat had both V and VR wires, stop now and contact a qualified contractor for help.
- If your old thermostat had separate O and B wires, attach the B wire to the C terminal. If another wire is attached to the C terminal, stop now and contact a qualified contractor for help.
- If your old thermostat had Y1, W1, and W2 wires, stop now and contact a qualified contractor for help.
- This model doesn’t support the heat pump fault alert (L/A terminal). If this is desired, please contact a contractor for a replacement model.
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 reached at the time you set. For example: Set the Wake time to 6 am, and the temperature to 70°. The heat will come on before 6 am, so the temperature is 70° by the time you wake at 6. The message “Recovery” is displayed when the system is activated before a scheduled time period.
Battery replacement
Batteries are required to provide power when a common wire is not used. Batteries are recommended to provide backup power if the common wire is used. Install fresh batteries immediately when the low battery icon appears. The icon appears about two months before the batteries are depleted. Even if the low battery icon does not appear, you should replace batteries once a year, or before leaving home for more than a month. If batteries are inserted within two minutes, the time and day will not have to be reset. All other settings are permanently stored in memory and do not require battery power. NOTE: When replacing batteries, alkaline batteries are recommended.
1-year limited warranty
Resideo warrants this product, excluding battery, to be free from defects in workmanship or materials, under normal use and service, for a period of one (1) year from the date of first purchase by the original purchaser. If at any time during the warranty period, the product is determined to be defective due to workmanship or materials, Resideo shall repair or replace it (at Resideo’s option). If the product is defective, (i) return it, with a bill of sale or other dated proof of purchase, to the place from which you purchased it; or (ii) call Resideo Customer Care at 1-800-468-1502.
Customer Care will make the determination whether the product should be returned to the following address: Resideo Return Goods, 1985 Douglas Dr. N., Golden Valley, MN 55422, or whether a replacement product can be sent to you. This warranty does not cover removal or reinstallation costs. This warranty shall not apply if it is shown by Resideo that the defect was caused by damage that occurred while the product was in the possession of a consumer. Resideo’s sole responsibility shall be to repair or replace the product within the terms stated above.
RESIDEO SHALL NOT BE LIABLE FOR ANY LOSS OR DAMAGE OF ANY KIND, INCLUDING ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES RESULTING, DIRECTLY OR INDIRECTLY, FROM ANY BREACH OF ANY WARRANTY, EXPRESS OR IMPLIED, OR ANY OTHER FAILURE OF THIS PRODUCT. Some states do not allow the exclusion or limitation of incidental or consequential damages, so this limitation may not apply to you. THIS WARRANTY IS THE ONLY EXPRESS WARRANTY RESIDEO MAKES ON THIS PRODUCT. THE DURATION OF ANY IMPLIED WARRANTIES, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE,
IS HEREBY LIMITED TO THE ONE-YEAR DURATION OF THIS WARRANTY. Some states do not allow limitations on how long an implied warranty lasts, so the above limitation may not apply to you. This warranty gives you specific legal rights, and you may have other rights which vary from state to state. If you have any questions concerning this warranty, please write Resideo Customer Care, 1985 Douglas Dr, Golden Valley, MN 55422, or call 1-800-468-1502.
REFERENCE LINK
https://www.manua.ls/honeywell/rth8500d/manual
