Honeywell RTH3100C User manual

Installation
Guide
RTH3100C
Non-Programmable Digital Thermostat
69-1889EF-1

Read and save these instructions.
® U.S. Registered Trademark. Patents pending.
Copyright © 2006 Honeywell International Inc. All rights reserved.
Need Help?
For assistance with this product please visit http://yourhome.honeywell.com
or call Honeywell Customer Care toll-free at 1-800-468-1502
CAUTION: ELECTRICAL HAZARD
Turn off power at the furnace or the fuse/circuit breaker panel before you begin.
MERCURY NOTICE
If this product is replacing a control that contains mercury in a sealed tube, do not
place the old control in the trash. Contact your local waste management authority for
instructions regarding recycling and proper disposal.

RTH3100C
1
Getting started
Installation tips...........................................2
Pre-installation checklist ...........................3
Old thermostat removal
Remove old thermostat.............................5
Identify and label wires..............................6
New thermostat installation
Wallplate mounting .................................... 8
Wire connections .....................................11
Battery installation...................................13
Thermostat mounting ..............................14
System setup
How to change settings...........................15
Set auxiliary heat cycle rate....................16
Set emergency heat cycle rate ...............17
Set temperature display ..........................18
Appendices
In case of difficulty...................................19
Customer assistance ............................... 21
Accessories.............................................. 21
1-year limited warranty............................22
Table of contents

Installation Guide
2
Your new thermostat has been designed for fast, easy installation. Just follow the
simple, step-by-step instructions in the following pages.
Install in three simple steps
• Label wires and remove your old thermostat (see pages 5-7).
• Install and wire your new thermostat (see pages 8-14).
• Set your new thermostat to match your heating/cooling system
(see pages 15-18).
Installation tips
• Have everything you need ready to go before you begin (see pages 3-4).
• Do not use wire color as a guide. Use wire labels instead (see page 7).
Installation is easy — even if you’ve never done it before!

RTH3100C
3
About your new thermostat
RTH3100C thermostat
(wallplate attached to back)
Operating Manual
Wall anchors and
mounting screws
(2 each)
Wire Labels
Check to make sure your package includes the following items:
Pre-installation checklist

Installation Guide
4
Required tools & supplies
• No. 2 Phillips screwdriver
• Small pocket screwdriver
• Drill
• Drill bit (3/16” for drywall, 7/32” for plaster)
• Hammer
• Pencil
• Electrical tape
• Level (optional)
• Two fresh AA alkaline batteries
Pre-installation checklist

RTH3100C
5
1. Turn off power at heating/cooling system (or fuse/circuit-breaker panel).
2. Remove cover and thermostat, but leave wallplate with wires attached.
Remove your old thermostat
Leave wallplate in place.
Old thermostat
Cover
Is there a sealed tube containing mercury?
If so, see inside front cover of this manual
for proper disposal instructions.

Installation Guide
6
Do not use unconnected wires.
If any wires are not attached to terminals in your old thermostat, do not connect them
to your new thermostat.
Wrap the bare metal ends of each unused wire with electrical tape, so it cannot touch
and short out other wires.
Identify wires you will not use

RTH3100C
7
Use a screwdriver to disconnect wires one by one. As you disconnect each wire,
wrap it with the label matching the letter on your old thermostat. (Adhesive labels are
supplied in your thermostat package.)
Remove the old wallplate only after all wires are labeled. Be careful not to let loose
wires fall into the wall opening.
Label wires and remove old wallplate
Wrap supplied labels securely around each wire.
Do not let wires fall into wall opening!
E
O
Aux
IGNORE WIRE COLORS:
Use only letter designations to identify wire types.

Installation Guide
8
PULL HERE
HIPS
Pull at bottom to remove thermostat from wallplate.
Remove wallplate
Wallplate

RTH3100C
9
About your new thermostat
1. Pull wires through wallplate. 3. Mark positions of
both screw holes.
2. Level wallplate if desired
(lay level across tabs).
Mark wallplate mounting position

Installation Guide
10
1. Drill holes at pencil-marked locations:
3/16” holes for drywall
7/32” holes for plaster
2. Use hammer to tap anchors
into holes until flush with wall.
3. Place wallplate over anchors
and insert screws. Check level
if desired, then tighten screws.
Mount wallplate

RTH3100C
11
1. Match each labeled wire
with same letter on terminal.
2. Use a screwdriver to
loosen screw terminals,
insert wires, then tighten
screws.
3. Push any excess wire back
into the wall opening.
Labels don’t match?
If labels do not match letters
on thermostat, see next page.
Connect wires (typical installation)

Installation Guide
12
Aux Y G O L R B CE
Aux Y G O L R B CE
4 33 2 1 2 2
or
X
X2
or
W
W1
W2
or
Y1
M
or
F
or
F
or
V
VR
or
H
or
B
X
If labels do not match thermostat letters,
check the chart at right (see notes, below).
Connect wires (less common wire designations)
If the old thermostat had both V
and VR wires, contact a heating/
cooling contractor for help.
If the old thermostat had both O
and Bwires, attach the Bwire to
the Cterminal. If another wire is
attached to the Cterminal, call
1-800-468-1502 for help.
If the old thermostat had W1, W2
and Ywires, contact a heating/
cooling contractor for help.
If no wire matches the Eterminal on the new thermostat,
use a small piece of wire to connect terminals Eand Aux.

RTH3100C
13
Install two fresh AA alkaline
batteries in back of thermostat.
Install batteries
Back of thermostat

Installation Guide
14
Thermostat
1. Align the 4 tabs on the wallplate
with corresponding slots on the
back of the thermostat, then
push gently until the thermostat
snaps into place.
2. Restore electrical power at the
heating/cooling system, or at the
fuse/circuit-breaker panel.
Mount thermostat and restore electrical power
Wallplate
TIP:
If wires interfere when you
try to mount the thermostat,
push excess wire back into the
wall opening.

RTH3100C
15
Setup
6
5
Function
number
Setting
To begin, press and hold the sand t
buttons until the display changes. Press tto change settings.
Press sto advance to next function.
Press and hold ts to exit and save settings.
Next, you must set the thermostat to control the heating and cooling system in your
home. Press and hold the sand tbuttons to enter system setup.
System setup (set thermostat to match your system)

Installation Guide
16
Setup
6
5
Press to change setting.
When finished, press
to advance to the next
function.
Press the tbutton to select your auxiliary
heating system and optimize its operation:
5For gas or oil furnaces of less than 90%
efficiency
1For steam or gravity systems
3For hot water systems & furnaces of over 90%
efficiency
9For electric furnaces
Function 6: Auxiliary heat cycle rate

RTH3100C
17
Setup
8
9
Press to change setting.
When finished, press
to advance to the next
function.
Press the tbutton to select your emergency
heating system and optimize its operation:
9For electric furnaces
1For steam or gravity systems
3For hot water systems & furnaces of over 90%
efficiency
5For gas or oil furnaces of less than 90%
efficiency
Function 8: Emergency heat cycle rate

Installation Guide
18
Setup
14
0
Press to change setting.
When finished, press and
hold both buttons to exit
and save changes.
Press the tbutton to select Fahrenheit or
Celsius temperature display:
0Fahrenheit temperature display (°F)
1Celsius temperature display (°C)
Function 14: Temperature display