Honeywell RTH2300 series User manual

Owner’s Manual
Read and save these
instructions.
For help please visit
yourhome.honeywell.com
RTH2300/RTH221
Series
Programmable
Thermostat
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.

2
NOTICE: To avoid possible compressor damage, do not run air
conditioner if the outside temperature drops below 50°F (10°C).
ATTENTION: MERCURY RECYCLING NOTICE
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
www.thermostat-recycle.org.
For mercury thermostat recycling in Canada,
please refer to Switch the Stat at
www.switchthestat.ca
NO MERCUR
Y
NO BOTE
MERCURIO
Hg
RTHXXXX
M32707
Customer assistance
For assistance with this product, please visit
http://yourhome.honeywell.com.
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
wallplate.
Turn thermostat over to find model number
and date code.

3
Installation
Installation............................................3
Advanced Installation...........................8
About your new thermostat
Controls and Home screen
quick reference...................................10
Preset energy-saving schedules........11
Programming and operation
Setting the clock.................................11
Adjusting program schedules.............12
Overriding schedules temporarily ......13
Overriding schedules permanently ....13
Compressor protection.......................14
Change filter.......................................14
Replace batteries ...............................15
Appendices
Troubleshooting..................................16
Limited warranty.................................17
Table of contents
1 Turn Off Power to Heating/Cooling System
or
M31535
Circuit breaker
box Heating/cooling system power switch

4
Do not remove wallplate yet
3 Label Wires with Tags
Label the wires using the supplied wire labels as you disconnect them.
Wire Labels
M28100
M32731
TO REMOVE WALLPLATE
PULL HERE
Wallplate
C
C
MCR33823
Terminal
designation
If you have an older thermostat with a
sealed mercury tube, turn to page 2
for proper disposal instructions.
Terminal designation
C
C
MCR31537
2 Remove Old Thermostat
Remove old thermostat but leave wallplate with wires attached.
4 Separate Wallplate from New Thermostat
Remove wallplate from the new thermostat and mount onto wall.

5
5 Mount Wallplate
Mount the new wallplate using the included screws and anchors.
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 here (see notes, below).
Thermostat does not work on Heat Pumps with auxiliary/backup heat.
We are here to help. Call 1-800-468-1502 for wiring assistance.
W/
Aux
Not
Used
M32714
Remove metal
jumper if you
have both Rand
Rc wires.
M32732
SCREW
INSERT WIRES
AND TIGHTEN
SCREWS
WIRE
HOLE
LABELED
WIRES
W
G
R
Not
Used
W
Y

6
Alternate Wiring
If wires will be connected to both Rand Rc terminals, remove metal
jumper.
Do not use Cor X. Wrap bare end of wire with electrical tape.
If you have a heat pump without auxiliary/backup heat connect Oor B,
not both. If you do not have a heat pump, do not connect B. Wrap bare
end of wire with electrical tape.
Place a jumper (piece of wire) between Yand Wif you are using a heat
pump without auxiliary/backup heat.
B O G Y
WNOT
USED
R Rc
M32734
44
7 Install Batteries
Install two AAA alkaline batteries.
Back of thermostat
RTHXXXX
M32707

7
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.)
9 Install Thermostat onto
Wallplate
Install thermostat onto the wallplate on
the wall.
RTHXXXX
M32716
GAS OR OIL
ELECTRIC OR HEAT PUMP
GAS OR OIL
ELECTRIC OR HEAT PUMP
10 Turn Power Back On
Turn the power back on to
the heating/cooling system.
W/
Aux
Not
Used
Heat Off Cool Auto On
Fan
M33784
Heat Off Cool Auto On
Fan
Heat Off Cool
Auto On
Fan
Set
Hold
Run
M31544
or
Circuit breaker box Heating/cooling system
power switch

8
11 If your system type is...
If your system type is:
qSingle Stage Heat and Cool
qHeat Only or Cool Only
Congratulations, you’re done!
If your system type is:
qHeat pump
qHigh efficiency furnace
qHot water
qElectric furnace
qGas/oil steam
qGravity system
Continue with Advanced Installation to match your thermostat to your system
type.
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
Enter System Setup
To enter system setup, press and hold
both the sand tbuttons until the display
changes (approximately 5 seconds).
Changing Settings
1. Press the sor tbutton to change
the setting.
2. Press the sand tbuttons
simultaneously for one second to
advance to the next function.
3. Press the RUN button to exit and save
settings.
M33785
Heat Off Cool Auto On
Fan
Heat Off Cool Auto On
Fan
Set
Hold
Run
Function
Setting
55
M33786
Set
Hold
Run

9
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 sor tbutton to Setting
5 select your heating system and
optimize its operation
5 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.
14 select Fahrenheit or Celsius
temperature display
0 Fahrenheit temperature display (°F)
1 Celsius temperature display (°C)
15* select Compressor Protection
settings
1 On
0 Off
20 select clock display 012-hour display
124-hour display
21
(RTH2300
only)
select Change Filter Timer 0Off
130 days
290 days
36 months
49 months
51 year
40
(RTH2300
only)
restore program schedule to
default settings
0 Off
1 On: Program schedule default settings are listed on
page11.
* 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.
• Backlit display on RTH2300
• Displays ambient (measured) temperature at all times
• One-touch access to setpoint temperature
• Preset program settings
• Temporary and permanent override of schedule
• Built-in compressor protection

10
Thermostat controls
M33612
Heat Off Cool Auto On
Fan
Heat Off Cool Auto On
Fan
Set
Hold
Run
Set: Press to set
time/day/schedule.
Hold: Press
to override
programmed
temperature
control.
Run: Press to
resume program
schedule.
Temperature
adjustment
Press the up or
down buttons
until you reach
the desired
temperature.
NOTE: Make sure
the SYSTEM switch
is set to the system
you want to control
(Heat or Cool).
Fan Switch is used to control your fan.
In “Auto” mode, the fan runs only when
the heating or cooling system is on.
If set to “On,” the fan runs continuously.
System Switch is used to control
your heating or cooling system.
• Heat: Heating system control.
• Off: All systems off.
• Cool: Cooling system control.
Display screen
M32701
We
Lo
Batt
Wake
Set
am
Heat
75
On
6:30
Low battery warning
(see page 15)
Setpoint indicator
Appears when the setpoint
temperature is displayed.
Temperature
The ambient (measured)
temperature is normally displayed.
To view the setpoint temperature,
press the Up or Down button
once. The setpoint temperature will
appear for five seconds.
System status
Cool on: Cooling system is on.
Heat on: Heating system is on.
When Cool On is flashing, compressor
protection is engaged (see page 14).
Current day/time
(see page 11)
Current program period
Wake/Leave/Return/Sleep
(see pages 11–13)