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.

2 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

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 Record if you have wires in the following terminals. Do not include jumpers as a part of your count. The thermostat does not need jumpers.

7 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):


The RTH8500 thermostat does not support S or U terminals.
8 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.



9 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.

10 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.
a) Level the wall plate.
b) Mark the location of the wall anchors using a pencil.
c) Drill the holes.
d) Insert wall anchors.
e) Make sure anchors are flush with wall.
Tip: If your box contains red anchors, drill 7/32” holes. If your box contains yellow anchors, drill 3/16” holes.

11 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.
If you have 1 R-wire (R,Rh, or Rc)
1. Set R-switch to the up position.
2. Insert your R-wire (R, Rh or Rc) into R-terminal.
or If you have 2 R-wires (R or Rh, and Rc)
1. Set R-switch to the down position.

2. Insert your Rc wire into Rc-terminal
3. Insert your R or Rh wire into R-Terminal.
12 Connect wires from Step 7.
Depress 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. Gently tug on the wires to verify they are secure.
Tip: If you need to release the wires again, push down the terminal tabs on the sides of the UWP

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

14 Confirm wiring matches snapshot.
Please confirm wiring matches terminals from the photo you took in Step 5.
15 Install batteries.
Insert three AA alkaline batteries in the back of the thermostat as shown.
NOTE: The RTH8500 thermostat works in battery mode or normal power mode if a C-wire is available.

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

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

18 Return to the thermostat
Return to the thermostat. Confirm the screen shows START SETUP. If your thermostat does not show START SETUP, please contact Honeywell Home support.
19 Start setup.
Touch START SETUP to begin

20 Navigate and edit setup options.
Use the
or
to navigate through all the setup options. To see a list of all setup options, go to pages 9-10. To edit an option, touch Edit or touch text area. The value is now blinking. Use
or
to select the correct value. Touch Done or touch text area once the correct value is selected.

21 Finish setup.
Touch
until you see FINISH SETUP. Touch Select or touch text area.

22 Set time and date.
Set daylight saving time if you are in an area that follows daylight saving time. Set date, clock format, and time on the next screens.

23 Your thermostat is now setup.
Refer to page 8 for more information about basic operation.

To access all system options in the table below, press and hold MENU for 5 seconds. Touch
or
to scroll through the list.
Number : 120
Description Scheduling Options
Options (factory default in bold)
Number: 125
Description Temperature Indication Scale
Options (factory default in bold)
Number: 200
Description Heating System Type
Options (factory default in bold)
Number: 205
Description Heating Equipment Type
Options (factory default in bold)
Conventional Forced Air Heat:
Radiant Heat:
Number: 218
Description Reversing Valve O/B
Options (factory default in bold)
Number: 220
Description Cool Stages / Compressor Stages 200=Conv / 200=HP
Options (factory default in bold)
Number: 221
Description Heat Stages / Backup Heat Stages Heat Stages
Options (factory default in bold)
Number: 230
Description Fan Control
Options (factory default in bold)
Number: 300
Description System Changeover
Options (factory default in bold)
Number: 303
Description Auto Differential
Options (factory default in bold)
Number: 365
Description Cool 1 CPH (Cooling cycle rate stage 1)
Options (factory default in bold)
Number: 366
Description Cool 2 CPH (Cooling cycle rate stage 2)
Options (factory default in bold)
Number: 370
Description Heat 1 CPH (Heating cycle rate stage 1)
Options (factory default in bold)
Number: 371
Description Heat 2 CPH (Heating cycle rate stage 2)
Options (factory default in bold)
Number: 375
Description Aux Heat CPH (Heating cycle rate Auxiliary Heat)
Options (factory default in bold)
Number: 425
Description Smart Response
Options (factory default in bold)
Number: 430
Description Minimum Cool Temperature Setpoint
Options (factory default in bold)
Number: 431
Description Maximum Heat Temperature Setpoint
Options (factory default in bold)
Number: 702
Description Air Filters
Options (factory default in bold)
Number: 711
Description Air Filter 1 Replacement Reminder
Options (factory default in bold)
Number: 1401
Description Idle Brightness
Options (factory default in bold)
Number: 1410
Description Clock Format
Options (factory default in bold)
Number: 1415
Description Daylight saving time
Options (factory default in bold)
NOTE: Once you have cycled through all of the System Setup numbers, Done is displayed. Press Select to save and exit.
1 Press the Mode button to cycle to the next available System mode.
2 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: Thermostat selects heating or cooling as needed.
‒ Heat: Thermostat controls only the heating system.
‒ Cool: Thermostat controls only the cooling system.
‒ Em Heat (only for heat pumps with auxiliary heat): Thermostat controls Auxiliary Heat. Compressor is not used.
‒ Off: Heating and cooling system is off. Fan will still operate if fan is set to On or Circulate.


1 Press the Fan button to cycle to the next available Fan mode.
2 Cycle through the modes until the required Fan mode is displayed and leave it to activate.

NOTE: 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 circulates randomly about 33% of the time.

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.

NOTE: To temporarily or permanently override any of the above program schedules, see page 13.
1 Touch Menu on the thermostat home screen.
2 Touch the or arrows until you see SCHEDULE, then touch Select.
3 Touch the
or
arrows to select a period in a day or set of days, then touch Select on the period you want to edit. (You can only edit a period of days according to the schedule type selected. To change schedule type, see setup # 120 on page 9.)
4 Touch the time area, then touch
or
to adjust when the period starts. Touch Select to confirm.
5 Touch the temperature area, then touch
or
to adjust your preferred temperature for the mode that’s currently active (either heating or cooling). Touch Select to confirm. Then touch
or
to adjust your preferred temperature for the inactive mode. Touch Select to confirm.



6 Edit the next period or use the until you see Done, then press Select to save changes and go to the home screen.



Hold Until (temporary hold): Overrides the current temperature setpoint for a maximum of 12 hours. You might use this feature to hold a temperature until a specific time.
Permanent hold: Overrides the current temperature set point permanently until you manually change it or reactivate a schedule.
Program schedule override (temporary)
1 Touch
or
on the thermostat home screen to set your desired temperature. Hold Until will appear together with the time the hold will end.
2 To change when the hold will end, touch the time and wait until the time starts blinking. Then, touch
or
to set when you want the hold to end. Touch Hold Until once more to confirm changes and return to the home screen.


NOTE: After the hold period ends, the thermostat will automatically return to the program schedule. If you want to cancel the hold, touch Hold Until and then touch Run Schedule.
Program schedule override (permanent)
1 Touch
or
on the thermostat home screen to reach your desired temperature. Hold Until will appear together with the time you want the hold to end.
2 Touch Hold Until. Permanent Hold will appear on screen. Touch Permanent Hold to hold this temperature until you manually change it.

NOTE: To end permanent hold and return to the program schedule, touch Permanent Hold and then touch Run Schedule
Alternate wiring (conventional systems)
If labels do not match terminals, connect wires as shown below (see notes, below).
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, wrap each separately with electrical tape and do not connect them.

Connect wires: heat pump
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.
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:
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.
5. This model doesn’t support the heat pump fault alert (L/A terminal). If this is desired, please contact a contractor for replacement model.

NOTE: Do NOT use W for heat pump applications. Auxiliary heat must wire to AUX or E.
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.

Batteries are required to provide power when common wire is not used. Batteries are recommended to provide backup power if 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.
Setting the time
1 Touch Menu on the thermostat home screen.
2 Touch the
or
arrows until you see CLOCK, then touch Select.
3 Touch the
or
arrows until you see SET TIME, then touch Select.
4 Press
or
to set the time (or press and hold the buttons to move more quickly). Touch Done when finished.
5 Set clock format (12 hours or 24 hours) and daylight saving time in the same CLOCK sub-menu.


Setting the date
1 Touch Menu on the thermostat home screen.
2 Touch the
or
arrows until you see DATE, then touch Select.
3 Touch
or
to set the month, then touch Select to confirm.
4 Continue to set day and year in the same way. Touch Select to save your changes.

To select a temperature scale, follow the steps below.
1 Touch Menu on the thermostat home screen.
2 Touch the
or
arrows until you see TEMP SCALE, then touch Select.
3 Touch the
or
arrows to select FAHRENHEIT or CELSIUS then touch Done to save your changes.
4 Touch Back to return to the thermostat home screen.

1 Touch Menu on the thermostat home screen, then you’ll see the ALERTS submenu. (The ALERTS sub-menu will only be available when there’s an active alert.)
2 Touch Select to view the alert. A 3-digit alert code will appear by the thermostat’s clock and a description of the alert will scroll on the screen.
3 If the alert is non-critical, you’ll have the option to Snooze or Dismiss it. If you have multiple alerts, touch the or arrows to page through the list of active alerts and follow steps 1 and 2 above. To see what each 3-digit alert code means and the action you should take, refer to the chart below.
Number : 170
Alert/Reminder: Internal Memory
Definition : The memory of the thermostat has encountered an error. Please replace the thermostat.
Number : 173
Alert/Reminder: Thermostat Temperature Sensor Error
Definition : The sensor of the thermostat has encountered an error. Please replace the thermostat.
Number : 181
Alert/Reminder: Replace Air Filter (1)
Definition : Replace air filter (1). Reset the timer by touching the "dismiss" button on thermostat screen after it is replaced.
Number : 405
Alert/Reminder: Low Battery Alert
Definition : The batteries are getting low. Replace them within two months
Number : 407
Alert/Reminder: Critical Low Battery
Definition : The batteries are almost depleted and should be replaced as soon as possible.
If you have difficulty with your thermostat, please try the following suggestions.
Most problems can be corrected quickly and easily.
Display is blank
Cannot change system setting to Cool
Fan does not turn on when heat is required
Heating system is running in cool mode
Heating or cooling system does not respond
Heat On / Cool On flashing on the screen
Heat pump issues cool air in heat mode, or warm air in cool mode
Check System Setup Option 200 or 218 to make sure it is set to match your heating and cooling equipment (see page 9).
Aux heat runs in cooling
Cool runs with a call for heat
Reference file: Honeywell RTH8560D 7 Day Programmable Touchscreen Thermostat
Series: RTH8500 Series