Honeywell RTH111 Series Non-Programmable Thermostat


Read and save these instructions.
For help please visit

Identify System Type
This thermostat is compatible with the following systems:

  • Gas, oil or electric furnace
  • Central air conditioner
  • Hot water system with or without pump
  • Millivolt system
  • Central heating and cooling system
  • Heat pump without auxiliary/backup heat

Do you need assistance? We are here to help.
Call 1-800-468-1502 for wiring assistance before returning the thermostat to the store. This thermostat cannot be used on heat pumps with backup heat or on multistage systems.

This product does not contain mercury. However, this product may replace a product that contains mercury. Mercury and products containing mercury should not be discarded in household trash. For more information on how and where to properly recycle a thermostat containing mercury in the United States, please refer to the Thermostat Recycling Corporation at
For mercury thermostat recycling in Canada, please refer to Switch the Stat at

NOTICE: To avoid possible compressor damage, do not run air conditioner if the outside temperature drops below 50°F (10°C).

image 1

Customer assistance
For assistance with this product, please visit Or call Honeywell Customer Care toll-free at 1-800-468-1502. To save time, please note your model number and date code before calling. Pull at bottom to remove thermostat from wall plate. Turn thermostat over to find model number and date code.

  1. Turn Off Power to Heating/Cooling Systemimage 2
  2. Remove Old Thermostat
    Remove old thermostat but leave wallplate with wires attached.image 3
  3. Label Wires with Tags
    Label the wires using the supplied wire labels as you disconnect them.image 4
  4. Separate Wallplate from New Thermostat
    Remove wallplate from the new thermostat and mount onto wall.image 5
  5. Mount Wallplate
    Mount the new wallplate using the included screws and anchors.image 6
    Drill 3/16-in. holes for drywall
    Drill 3/32-in. holes for plaster
  6. Connect Wires Simply match wire labels. If labels do not match letters on the thermostat, check “Alternate Wiring” on page 6 and connect to terminal as shown (see notes, below).image 7We are here to help. Call 1-800-468-1502 for wiring assistance.
    Alternate Wiring
    If labels do not match letters on the thermostat, check the chart below and connect to terminal as  shown here (see notes, below)image 8
    1. If wires will be connected to both R and Rc terminals, remove metal jumper
    2. Do not use C or X. Wrap bare end of wire with electrical tape.
    3. If you have a heat pump without auxiliary/backup heat connect O or B, not both. If you do not have a heat pump, do not connect B. Wrap bare end of wire with electrical tape.
    4. Place a jumper (piece of wire) between Y and W if you are using a heat pump without auxiliary/backup heat.
  7. Install Batteries
    Install two AAA alkaline batteries.image 9
  8. Set fan operation switch
    Move the switch to the proper setting:
    Gas or Oil: For gas or oil heating systems, leave the fan operation switch in this factory-set position (for systems that control the fan in a call for heat).
    Electric or Heat Pump: Change the switch
    to this setting for heat pump or electric heat systems. (This setting is for systems that allow the thermostat to control the fan in a call for heat, if a fan wire is connected to the G terminal.)image 10
  9. Install Thermostat onto Wallplate
    Install thermostat onto the wallplate on the wall.image 11
  10. Turn Power Back On
    Turn the power back on to the heating/cooling system.image 12
  11. If your system type is…
    If your system type is:
    • Single Stage Heat and Cool
    • Heat Only or Cool Only

Congratulations, you’re done!
If you are not sure of your system type or if you have other questions, call us toll-free at 1-800-468-1502. This thermostat works on 24 volt or 750 mV systems. It will NOT work on multi-stage conventional systems.

Advanced Installation

image 13

Enter System Setup
To enter system setup, press and hold both the s and t buttons until the display changes (approximately 5 seconds).Changing Settings

  1. Press the s or t button to change the setting.
  2. Press the s and t buttons simultaneously for one second to advance to the next function.
  3. When the last function is displayed, press the s and t buttons to save any changes and exit the menu.

NOTE: If you do not press any button for 60 seconds while you are in the setup menu, the thermostat automatically saves any changes made and exits the menu.

Function Description Press the sort button toSetting
5select your heating system and optimize its operation5  Gas or oil furnace: Use this setting if you have a standard gas or oil furnace that is less than 90% efficient.6  Electric furnace: Use this setting if you have any type of electric heating system.3 Heat pump, hot water or high-efficiency furnace: Use this setting if you have a hot water system or a gas furnace of greater than 90% efficiency.2 Gas/oil steam or gravity system: Use this setting if you have a steam or gravity heat system.
14select Fahrenheit or Celsius temperature display0  Fahrenheit temperature display (°F)1  Celsius temperature display (°C)
15*select Compressor Protection settings1 On0 Off

Compressor Protection:
This feature forces the compressor to wait approximately 5 minutes before restarting, to prevent equipment damage. During the wait time, the message “Cool On” or “Heat On” is displayed on screen.

About your new thermostat
Your new Honeywell thermostat has been designed to give you many years of reliable service and easy-to-use, push-button climate control.

  • Displays ambient (measured) temperature at all times
  • One-touch access to setpoint temperature
  • Built-in compressor protection.

Thermostat controls

image 14
image 15

Display screen

image 16

Built-in compressor protection
This feature helps prevent damage to the compressor in your air conditioning or heat pump system. Damage can occur if the compressor is restarted too soon after shutdown. This feature forces the compressor to wait 5 minutes before restarting. During the wait time, the display will flash the message Cool On (or Heat On if you have a heat pump). When the safe wait time has elapsed, the message stops flashing and the compressor turns on.

image 17

Battery replacement
Install two fresh AAA batteries when Lo Batt flashes on the screen. Lo Batt appears for 60 days before the batteries are depleted. Replace batteries once a year, or when you will be away for more than a month. Most settings are stored in non-volatile (permanent) memory. Only the clock and the day must be set after you replace the batteries.

image 18

Warning: Set the System switch to Off before removing the batteries. Otherwise, the heating/cooling system could remain activated even when batteries are removed.

Turn thermostat over, insert fresh AAA alkaline batteries, then reinstall thermostat.


table 1

If you have difficulty with your thermostat, please try the following suggestions. Most problems can be corrected quickly and easily.

For assistance with this product, please visit or call Honeywell Customer Care toll-free at 1-800-468-1502.

1-year limited warranty
Honeywell warrants this product, excluding battery, to be free from defects in the workmanship or materials, under normal use and service, for a period of one (1) year from the date of purchase by the consumer. If at any time during the warranty period the product is determined to be defective or malfunctions, Honeywell shall repair or replace it (at Honeywell’s option).
If the product is defective,

  1. (return it, with a bill of sale or other dated proof of purchase, to the place from which you purchased it; or
  2. call Honeywell Customer Care at 1-800-468-1502. Customer Care will make the determination whether the product should be returned to the following address: Honeywell Return Goods, Dock 4 MN10-3860, 1885 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 Honeywell that the defect or malfunction was caused by damage which occurred while the product was in the possession of a consumer.

Honeywell’s sole responsibility shall be to repair or replace the product within the terms stated above. HONEYWELL SHALL NOT BE LIABLE FOR ANY LOSS OR DAMAGE
do not allow the exclusion or limitation of incidental or consequential damages, so this limitation may not apply to you.

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 Honeywell Customer Relations, 1985 Douglas Dr, Golden Valley, MN 55422 or call 1-800-468-1502.


Automation and Control Solutions Honeywell International Inc.
1985 Douglas Drive North
Golden Valley, MN 55422
® U.S. Registered Trademark.
© 2015 Honeywell International Inc.
33-00136EF—01 M.S. 08-15
Printed in U.S.A.

Documents / Resources

Honeywell RTH111 Series Non-Programmable Thermostat [pdf] Owner’s Manual
RTH111 Series Non-Programmable Thermostat
Honeywell RTH111 Series Non-Programmable Thermostat [pdf] Owner’s Manual
RTH2510 Series, RTH2410 Series, RTH111 Series, Non-Programmable Thermostat
Honeywell RTH111 Series Non-Programmable Thermostat [pdf] User Manual
RTH111 Series, Non-Programmable Thermostat

Leave a comment

Your email address will not be published.