Remove old thermostat but leave wallplate with wires attached.
MERCURY NOTICE: Do not put your old thermostat in the trash if it contains mercury in a sealed tube. Contact your local waste management authority for instructions regarding recycling and proper disposal.
Do not remove wallplate yet
If any wires are not attached to your old thermostat or are attached to a terminal marked C or C1, they will not be connected to your new thermostat. Wrap the bare metal end of each of these wires with electrical tape, so it cannot touch and short other wires.
WARNING: Disconnect wires and remove the old wallplate only after all wires are labeled. Wrap the wires around a pencil to prevent them from falling though the wall opening.
If labeled wire does not match any terminal designation, see diagram below
Set jumper JP1, on the back of the thermostat, if you have connected a wire to the G terminal.
HG Leave the jumper in this factory-set position if you have a gas or oil furnace.
HE Place the jumper to this position if you have an electric furnace.
Incorrect jumper setting: An incorrect setting is noticeable in a gas or oil heating system. When heating starts, you will initially feel cold air coming out of the vents as the fan is running before the furnace has enough time to heat up the air.
Set jumper JP2, on the back of the thermostat, if you have a heat pump
O Leave the jumper in this factory-set position if you have connected O wire to the O/B terminal.
B Place the jumper to this position if you have connected B wire to the O/B terminal.
Incorrect jumper setting: The heat pump operation will be reversed, i.e., it will cool in Heat mode and will heat in Cool mode.
Follow the procedure below to personalize and configure the thermostat according to the heating/cooling system.
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. At any time you can save the changes and exit by pressing the Run button.
Press the or
button to select Fahrenheit or Celsius temperature display
When correct setting is selected, press both and
to display next function.
Press the or
button to select 12-hour display or 24-hour display
When correct setting is selected, press both and
to display next function.
Note: Make sure system switch is in the heat position.
Press the or
button to select your heating system and optimize its operation:
2 to 6 cycles per hour
5 12 min, Gas or oil furnace. Use this setting if you have a standard gas or oil furnace that is less than 90% efficient.
2 30 min, Steam or gravity system. Use this setting if you have a steam or gravity heat system.
3 20 min, 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.
4 15 min, Gas or oil furnace. Use this setting if you have a standard gas or oil furnace that is less than 90% efficient.
6 10 min, Electric furnace: Use this setting if you have any type of electric heating system.
When correct setting is selected, press both and
to display next function.
Press the or v button to select compressor protection:
WARNING: 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 message Cool On or Heat On flashes on the screen. When the safe wait time has elapsed, the message stops flashing and the compressor turns on.
When correct setting is selected, press the and
buttons to save any changes and exit the menu.
Reference file: Honeywell RTH2300B1012 5-2 Day Programmable Thermostat
Additionally, the document applies to other Honeywell models: RTH221