Honeywell RTH3100C User manual

Operating
Manual
RTH3100C
Non-Programmable Digital Thermostat
69-1890EF-1

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Copyright © 2006 Honeywell International Inc. All rights reserved.
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RTH3100C
1
About your new thermostat
Thermostat features...................................2
Quick reference to controls.......................3
Quick reference to display ........................4
Thermostat Operation
System switch (Heat/Cool)........................5
Fan switch (Auto/On) .................................6
Temperature controls.................................7
Compressor protection..............................8
Appendices
Battery replacement ..................................9
In case of difficulty...................................10
Customer assistance ............................... 12
Accessories............................................. .12
1-year limited warranty............................13
Table of contents

Operating Manual
2
Congratulations on the purchase of your new Honeywell thermostat. It has been
designed to give you many years of reliable service and easy-to-use, push-button
climate control.
Features
• One-touch temperature controls
• Large, clear backlit display is easy to read, even in the dark
• Switchable fan control (auto or continuous fan)
• Displays both room temperature and temperature setting
• Built-in compressor protection
About your new thermostat

RTH3100C
3
About your new thermostat
Temperature adjustment
Press to adjust temperature
settings.
Fan Switch (see page 6)
On: Fan runs continuously.
Auto: Fan runs only when
heating or cooling system is on.
Quick reference to controls
System switch (see page 5)
• Cool: Cooling system control.
• Off: All systems off.
• Heat: Heating system control.
• Em Heat: Emergency & Auxiliary
Heat control. Compressor is
locked out.
Digital display screen

Operating Manual
4
System Status
• Cool On: Cooling system is on.
• Heat On: Heating system is on.
• Em: Emergency heat is on.
• Aux: Auxiliary heat is on.
Quick reference to display screen
Heat On
Set To
Inside
75
75
Replace Batt
Current inside temperature Temperature setting
If flashing, compressor
protection is engaged
(see page 8).
Low battery warning

RTH3100C
5
The SYSTEM switch can be set to control
your heating or cooling system, depending
on the season.
• Cool: Cooling system control.
• Off: All systems are off.
• Heat: Heating system control.
• Em Heat: Emergency & Auxiliary Heat
control. Compressor is locked out.
System switch
Set SYSTEM switch to control the
heating or cooling system.
CAUTION: EQUIPMENT DAMAGE
HAZARD. Do not operate cooling
system when outdoor temperature
is below 50°F (10°C).

Operating Manual
6
Fan switch
Set the FAN switch to Auto or On.
In “Auto” mode (the most commonly used
setting), the fan runs only when the heat-
ing or cooling system is on.
If set to “On,” the fan runs continuously.
Use this setting for improved air circula-
tion, or for more efficient air cleaning.
Set FAN switch to choose whether the fan
runs continuously or only as needed.

RTH3100C
7
About your new thermostatTemperature controls
Press the temperature adjustment
buttons until the temperature you want
is displayed in the upper right portion of
the screen.
Note: Make sure the SYSTEM switch is set
to the system you want to control (Heat or
Cool).
Desired
temperature
Temperature
adjustment buttons
Cool On
Set To
78
Inside
75

Operating Manual
8
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 fea-
ture forces the compressor to wait for a few
minutes before restarting.
During the wait time, the display will flash the
message Cool On or Heat On. When the safe
wait time has elapsed, the message stops
flashing and the compressor turns on.
Message flashes until safe restart
time has elapsed.
Built-in compressor protection
Cool On
Set To
Inside
75
75