Honeywell Home RTH Series X2S Smart Thermostat

Specifications:

• Model: X2S Smart Thermostat
• Compatibility: RTH2CWF, RTHC2CWF, RTH2SMC

Pro Installation and Wiring:
To install the X2S Smart Thermostat, follow these steps:

1. Turn off power at the breaker box or switch controlling your heating/cooling system.
2. Check that the system is off by adjusting the temperature on your old thermostat.
3. Remove the old thermostat’s faceplate carefully without disconnecting any wires.
4. Check for any 120/240V wires, as the thermostat may not work with line voltage systems.
5. Take a picture of the current wiring for reference and note any jumpers present.
6. Record the wires in terminals R, RH, and Rc along with their colors.

FAQ:

• Q: What tools are needed for thermostat installation? 
  A: You will need a Phillips screwdriver, small flat head screwdriver, smartphone for photos, pencil, level, wire stripper, needle-nose pliers, and drill with a 3/16-inch bit.
• Q: How can I access Smart Alerts on the thermostat?
  A: Smart Alerts can be accessed through the thermostat’s interface or via push notifications on your smartphone when connected through the app.

Package includes:

Get the most from X2S Smart Thermostat
Multiple programming options that fit your lifestyle:

1. Location-Based scheduling (Auto Away)– The thermostat uses your smartphone’s location to know when you’re away, and saves you energy. Through geofence technology, it senses your return and helps make you comfortable upon arrival. You can always manually change your preset Home and Away temperature either on the thermostat or on the First Alert app.
2. Smart scheduling – Use a combination of geofencing and time scheduling to fit your busy, active lifestyle.
3. Time-Based scheduling – Program your thermostat for one week; each day (each day is a different schedule); Mon-Fri, Sat, Sun; or Mon-Fri, Sat-Sun. All days with four adjustable periods per day.

Smart Alerts. Push notifications remind you of filter changes and warn you of extreme indoor temperatures.
Smart Response. Learns your heating and cooling system to deliver the optimal temperature at the right time.
Auto Change From Heat to Cool. Automatically determine if your home needs heating or cooling to provide maximum comfort.

Tools you will need:

You may need:

Compatibility

• For indoor use only
• Compatible with most heating, cooling, and heat pump systems
• Required: 24 VAC power (“C” wire)
• Does not work with electric baseboard heat (120-240V)
• Does not support input (S terminals) for indoor and outdoor sensors
• Does not support relay (U terminals)
• Android or iOS smartphone, tablet, or device
• Compatible with a 2.4 or 5 GHz WiFi network

For help, contact:
WEB honeywellhome.com
PHONE 1-800-633-3991
SOCIAL Twitter: @Honeywell_Home, Facebook: Honeywell Home

READ AND SAVE THESE INSTRUCTIONS

Installation and Wiring

Removing the old thermostat

1. Turn power OFF.
   To protect yourself and your equipment, turn off the power at the breaker box or switch that controls your heating/cooling system. Some systems may have separate heating and cooling breakers.
2. Check that your system is off.
   Change the temperature on your old thermostat to be above room temperature in heat mode or below it in cool mode. 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
3. 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!
4. 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.
5. 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.
6. Make note of any jumpers
   A jumper connects one terminal to another terminal. It may look like a small staple or even a colored wire.
7. Record whether you have wires in the following terminals.
   Do not include jumpers as a part of your count. This thermostat does not need jumpers.
   Terminal Wire Color
8. Write down the color of the wires.
   Check mark the wires that are connected to terminals. Next to the check mark, write down the color of the wire. Do not include jumpers as a part of your count.
   Check all that apply (Not all will apply): S and U terminals are not supported with this thermostat.
   If there are wires in terminals that are not listed, you will need additional wiring support. Visit honeywellhome.com to find out if the thermostat will work for you.
9. 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.

Installing your X2S Thermostat

1. Bundle and insert wires through the UWP.
   Pull open the UWP and insert the bundle of wires through the back of the UWP.
   Make sure at least 1/4-inch of each wire is exposed for easy insertion into the wire terminals.
2. Insert the wall anchors.
   It is recommended that you use the wall anchors included in the box to mount your thermostat.
   You can use the UWP to mark where you want to place the wall anchors.
   • Level the wall plate.
   • Mark the location of the wall anchors using a pencil.
   • Using a 3/16” bit, drill the holes.
   • Insert wall anchors.
   • Make sure anchors are flush with wall.
3. Set R-switch position and insert R-wire or wires.
   Set the R-switch up or down based on your wiring notes in Step 7

Insert wires into the inner holes of the terminals on the UWP. The tabs will stay down once the wire is inserted.

NOTE: Wiring options are shown on the following pages. If you have 1 R-wire (R,Rh, or Rc)

If you have 2 R-wires (R or Rh, and Rc)

Wiring

Conventional Systems
Alternate wiring (conventional systems)
If labels do not match terminals, connect wires as shown below (see notes below).
WIRING NOTES:

1. . If you must connect both R and Rc wires, set the
   R Slider Tab to the down position (2 wires).
2. 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.
3. 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, call support for assistance.

Heat Pump

WIRING NOTES:

1. Match each labeled wire with same letter on new thermostat.
2. Insert the wires into the matching terminal.

NOTE: If you have difficulty inserting wires, you may have to press down the terminal push button next to the corresponding terminal. If the labels do not match the letters on the thermostat, see the diagram above.

Alternate wiring (for heat pumps only)

WIRING NOTES:

1. Keep R Slider Tab in the up position (1 wire).
2. If your old thermostat had both V and VR wires, stop now and contact a qualified contractor for help.
3. 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.
4. If your old thermostat had Y1, W1 and W2 wires, stop now and contact a qualified contractor for help.
   IMPORTANT: Do NOT use W for heat pump applications. Auxiliary heat must wire to AUX or E.

Connect wires to the UWP.
Refer to the notes you recorded on the chart during removal. Press down the tabs to put the wires into the inner holes of their corresponding terminals on the UWP (one wire per terminal) until it is firmly in place. Confirm wiring matches snapshot.
Confirm wiring matches terminals from the photo you took during removal.

Mount the UWP and close the door.
Mount the UWP using the provided screws. Install all three screws for a secure fit on your wall. Close the door after you’re finished.

Attach your thermostat.
Align the thermostat onto the UWP and firmly snap it into place.

Turn your power ON.
Turn on the power at the breaker box or switch that controls the heating/cooling system.

Return to the thermostat
Return to the thermostat. Confirm the screen shows SETUP. If it does, either select USING APP and continue to “Setup Using App” below or select ON DEVICE and continue to “Configuration” on the next page.

System Setup
Setup with First Alert by Resideo App

1. Start setup with the app
   Touch USING APP on thermostat
2. Your thermostat is ready to be configured using the First Alert app
   • Download the First Alert app from the App Store or Google Play.
   • Open the First Alert app. Your thermostat should appear under thermostat found. Tap SET UP NOW as shown below to continue. If your thermostat doesn’t appear, create an account (if necessary), or sign in to your First Alert account. Then select the X2S thermostat to install.
   • The First Alert app will walk you through the rest of setup.

Configuration

Set Time and Date
During installation the thermostat will already have the year flashing once you select ON DEVICE.

NOTE: Time and date are set automatically when the customer registers the thermostat to a First Alert account.

Time

1. Press MENU on the thermostat
2. Press ↑ or ↓ to go to TIME and press SELECT
3. Press ↑ or ↓ to choose 12 or 24 hour clock format and press NEXT
4. Press ↑ or ↓ to adjust the hour and press NEXT
5. Press ↑ or ↓ to adjust the minute and press SAVE & EXIT

Date

1. Press MENU on the thermostat
2. Press ↑ or ↓ to go to DATE and press SELECT
3. Press ↑ or ↓ to choose YEAR and press NEXT
4. Press ↑ or ↓ to choose MONTH and press NEXT
5. Press ↑ or ↓ to choose DATE and press SAVE & EXIT

System Setup
On initial setup, the thermostat will enter the ISU menu after setting the time and date. If entering the ISU menu after initial setup, follow the steps below:

1. Press and hold the bottom left button and Up arrow ↑ button for 5 seconds to access the INSTALLER SETUP
2. The display shows the ISU number on the left and the ISU setting on the right. When an ISU number is displayed, press ↑ or ↓ to change the setting for that ISU.
3. After choosing the correct setting for an ISU, press NEXT to advance to the next ISU setting.
4. To finish setup, press the SAVE & EXIT button; this will save your settings and return to the Home screen.

Installer Setup Options (ISU)
Depending on system settings, not all options may be available

Installer Setup Options, continued from the previous page

Built-in Compressor Protection

Damage can occur if your system’s compressor is restarted too soon after shutdown. This feature forces the compressor to wait for a few minutes before restarting. During the wait time, the display will show the message Waiting For Equipment under the room temperature reading. When the safe wait time has elapsed, the message disappears, and the thermostat will show “Heat on” or “Cool on”.

How to use your First Alert by Resideo App

Interested in more Resideo products? Visit honeywellhome.com to learn about all available products connected by the First Alert App. App is regularly enhanced and may change.

System Operation

Settings

1. Press the MODE button to cycle to the next available System mode
2. Cycle through the modes until the desired System mode is displayed
   Available System modes vary by model and system settings.

System modes:

• AUTO
• HEAT
• COOL
• EM HEAT
• OFF

Fan Operation Settings

1. Press the FAN button to cycle to the next available Fan mode
2. Cycle through the modes until the desired Fan mode is displayed Available Fan modes vary with system settings.

Fan modes:

• AUTO: Fan runs only when the heating or cooling system is on
• ON: Fan is always on
• CIRC: Fan runs about 33% of the time to circulate air

Program Schedule
You can program four time periods each day, with different settings for weekdays and weekends. We recommend using the presets shown in the table at right; these presets are designed to reduce your heating/cooling expenses.
WAKE: Set to the time you wake up and your desired temperature during the morning until you leave for the day.AWAY: Set to the time you leave home and your desired temperature while you are away (usually an energy-saving temperature).
HOME: Set to the time you return home and your desired evening temperature until bedtime.
SLEEP: Set to your bedtime and your desired overnight temperature (usually an energy-saving temperature).

Adjusting Program Schedules
(This could also be done using the First Alert App)

1. Press MENU. Press ↑ or ↓ until SCHED is displayed.
2. A square appears around ON or OFF in the display. If you want to use a schedule, press ↑ or ↓ to select ON. Press Select to edit the schedule or press EXIT to exit the menu.
3. If editing the schedule, press SELECT to edit the day or days flashing in the display.
4. The word Wake should be flashing. Press NEXT. Press ↑ or ↓ to turn this schedule period on or off. Selecting OFF will disable this schedule period. Press NEXT.
5. If the schedule period was set to ON, the time will be flashing. Press ↑ or ↓ to adjust the time for this period. Press NEXT.
6. The Heat setpoint will be flashing. Press ↑ or ↓ to adjust the Heat setpoint for this period. Press NEXT.
7. The Cool setpoint will be flashing. Press ↑ or ↓ to adjust the Cool setpoint for this period. Press NEXT.
8. The display will show the next schedule period flashing. Repeat steps 4 – 7 for the Away, Home and Sleep schedule settings. After completing all schedule settings for the day(s) selected, repeat these steps for the other days.
9. Press the SAVE & EXIT button at upper left.

When editing an existing schedule, you can advance to the setting you wish to change, edit that setting and press the SAVE & EXIT button to save changes.
Depending on what type of schedule the thermostat was set up for, days may be grouped or set individually.

Smart Response Feature

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 “Active Recovery” is displayed when the system is activated before a scheduled time period.

Program Schedule Override (Temporary)

1. Press ↑ or ↓ to adjust the temperature.
2. Once at the desired setpoint temperature, no further action is needed. The new setpoint temperature will be held until the next scheduled time period begins.
3.  Press the SAVE button or wait for the display to time out and return to the Home screen.

To cancel the Temporary Hold, press and release the HOLD button to cycle through the settings until CANCEL HOLD is selected.

Program Schedule Override (Permanent)

1. Press ↑ or ↓ to adjust the temperature.
2. Once at the desired setpoint temperature, press and release the HOLD button to cycle through the settings until HOLD PERMANANTLY is selected.
3. Press the SAVE button or wait for the display to time out and return to the Home screen.

To cancel the Permanent Hold, press and release the HOLD button to cycle through the settings until CANCEL HOLD is selected.

Alerts

When an alert is active, an icon  will appear in the lower part of the display.

1. Press MENU and use ↑ or ↓ until the alert is shown. Active alerts will be the first menu items shown.
2. Press SELECT to display the alert number.
3. An alert cannot be dismissed. If there is more than one active alert, pressing the NEXT button allows you to view any additional alert numbers. Press EXIT to return to the home screen.

Some alerts can be resolved by the homeowner, for example Set Time and Date. Other alerts may require a service call to the professional installer.

Reminders
When a reminder is active, a icon will appear in the lower part of the display.

1. Press MENU and use ↑ or ↓ until the active reminder is shown. Active alerts and reminders will be the first menu items shown.
2. Press SELECT to display the reminder.
3. Once selected you will see the reminder message in scrolling text. Press DISMISS to reset the reminder or press EXIT to return to the home screen without resetting the reminder.

If there is more than one active reminder, press the NEXT button to view all reminders which have not been reset.

Accent Piece Replacement
One white and one grey accent piece are provided with the X2S thermostats to accommodate different user preferences.

Troubleshooting

Frequently Asked Questions

Regulatory Information

FCC REGULATIONS 47 CFR § 15.19 (a)(3)

This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:

1. This device may not cause harmful interference, and
2. This device must accept any interference received, including interference that may cause undesired operation.

47 CFR § 15.21 (USA only)
Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.
47 CFR § 15.105 (b)
See https://customer.resideo.com/en-US/support/residential/codes-and-standards/FCC15105/Pages/default.aspx for additional FCC information for this product.

RF EXPOSURE STATEMENT

WARNING:
The antenna(s) used for these transmitters must be installed to provide a separation distance of at least 20 cm from all persons and must not be co-located or operating in conjunction with any other antenna or transmitter.
Operations in the 5150-5250 MHz band and in the 5250-5350 MHz band are restricted to Indoor use only.

2-year Limited Warranty

For Warranty information go to Honeywellhome.com/support

IC REGULATIONS
RSS-GEN
This device contains licence-exempt transmitter(s)/receiver(s) that comply with Innovation, Science and Economic Development Canada’s licence-exempt RSS(s). Operation is subject to the following two conditions:

1. This device may not cause interference.
2. This device must accept any interference, including interference that may cause undesired operation of the device.

RF EXPOSURE STATEMENT

WARNING:
The antenna(s) used for these transmitters must be installed to provide a separation distance of at least 20 cm from all persons and must not be co-located or operating in conjunction with any other antenna or transmitter. Operations in the bands 5150-5250 MHz and 5250-5330 MHz is only for indoor use to reduce the potential for harmful interference to co-channel mobile satellite systems

CAUTION: ELECTRICAL HAZARD
Can cause electrical shock or equipment damage. Disconnect power before beginning installation.

CAUTION: EQUIPMENT DAMAGE HAZARD
Compressor protection is bypassed during testing. To prevent equipment damage, avoid cycling the compressor quickly.

CAUTION: MERCURY NOTICE
If this product is replacing a control that contains mercury in a sealed tube, do not place the old control in the trash. Contact your local waste management authority for instructions regarding recycling and proper disposal.

CAUTION: ELECTRONIC WASTE NOTICE
The product should not be disposed of with other household waste. Check for the nearest authorized collection centers or authorized recyclers. The correct disposal of end-of-life equipment will help prevent negative consequences for the environment and human health.

FCC statement available at: https://customer.resideo.com/en-US/support/residential/codes-and-standards/FCC15105/Pages/default.aspx

Customer Assistance
For assistance with this product,  please visit honeywellhome.com Or call Resideo Customer Care toll-free at 1-800-633-3991

Resideo Inc., Scottsdale, AZ 85254 www.resideo.com 33-00689EFS-05 SA Rev. 01-25
This product is manufactured by Resideo Technologies, Inc., Scottsdale, AZ 85254 1-800-633-3991
©2025 Resideo Technologies, Inc. The Honeywell Home trademark is used under license from Honeywell International Inc. All rights reserved.

Documents / Resources

Honeywell Home RTH Series X2S Smart Thermostat [pdf] Installation Guide RTH2CWF, RTHC2CWF, RTH2SMC, RTH Series X2S Smart Thermostat, RTH Series, X2S Smart Thermostat, Smart Thermostat, Thermostat

References

• User Manual