Honeywell CT3400 User manual

Weekday/Saturday/Sunday
Programmable Heat and/or Cool
Low Voltage (20 to 30 Vac)Thermostat and Wallplate
Model CT3400/CT3455
PROGRAMMABLE
THERMOSTAT
Honeywell/34
PROGRAMMING AND INSTALLATION
INSTRUCTIONS
J.S. Rev. 4-97 ©Honeywell Inc. 1997 Printed in U.S.A. Form Number 69-0733—3
69-0733-3
30%
28%
26%
24%
22%
20%
18%
16%
14%
12%
8%
6%
2%
10%
4%
Minneapolis
St. Paul
Montreal
Ottawa
Toronto
Buffalo
Cleveland
Milwaukee
Edmonton
Regina
Winnipeg
Calgary
Moncton
North Bay
Quebec
St. John's
Halifax Vancouver Denver
Des Moines 
Omaha
Salt Lake
City
Boston
Chicago
Detroit
Pittsburgh
Indianapolis
Cincinnati
Kansas City
St. Louis
Columbus
New York
Philadelphia
Seattle
Louisville
Portland
Wash., D C
San 
Francisco
Dallas
Atlanta Los Angeles
Approximate percentage of energy cost savings
Savings for Once-A-Day
10°F (5°C) decrease Savings for Twice-A-Day 10°F (5°C) decrease* Savings for 5°F (3°) summer increase

TYPICAL ENERGY SAVINGS FOR REPRESENTATIVE CITIES IN THE U.S. AND CANADA
*Based on 10°F (5°C) decrease—(5°F [3°C] decrease
gives approximately 55 percent of these savings). M2416A
San Diego

TOTAL COMFORT TEMPERATURE MANAGEMENT
WITH ADAPTIVE INTELLIGENT RECOVERY™
Congratulations! You made a smart choice when you purchased your new Honeywell Thermostat.
It’s the smart thermostat that:
■
Keeps you comfortable by automatically calculating exactly when the furnace or air condi-
tioning should go on to have the house at the desired comfort temperature by the time you
wake up or return home.
■
Saves the maximum amount of energy and money by remembering to automatically adjust
the heat or air conditioning when you leave home or go to sleep.
■
Provides the ultimate in comfort and convenience . It comes already programmed, so it’s
your choice—use the preprogrammed schedule or set your own.
We invite you to spend a few minutes reading this manual. You’ll find it answers many of the
questions that will arise as you become familiar and comfortable with your Honeywell thermostat,
the state of the art in home comfort controls.
RecyclingThermostat
If this thermostat is replacing a control that
contains mercury in a sealed tube, do
not
place your old control in the trash. Contact
your local waste management authority for
instructions regarding recycling and the
proper disposal of this control, or of an old
control containing mercury in a sealed tube.
If you have questions, call Honeywell Inc. at
1-800-468-1502.
M3375
Fig. 1. Typical location of a mercury
switch in a thermostat.
M3701
MERCURY
SWITCH

STEP 1 Prepare For Installation
■■Check Table 1 to make sure this thermostat is compatible with your system. If not, return to retailer.
For more information, call Honeywell Customer Assistance, toll-free 1-800-468-1502.
Table 1. Compatibility Chart.
System Type Compatible with CT3400/3455
Gas—Standing Pilot Yes
Gas—Electronic Ignition Yes
Gas-Fired Boilers Yes
Gas—Millivolt No
Oil-Fired Boilers Yes
Oil-Fired Furnace Yes
Electric Furnace Yes
Electric Air Conditioning Yes
Baseboard Electric (120/240 line volt) No
Heat Pumps/Multistage Equipment No
Not compatible with any 120/240 volt circuit.
Compatible with 2-wire Honeywell and Taco zone valves. Not compatible with 3-wire zone valves
or 2-wire White Rodgers no. 1361 valves.
1 69-0733—3
Table Of Contents
STEP 1 Prepare For Installation.................................................................................................... 2
STEP 2 Remove Old Thermostat .................................................................................................. 4
STEP 3 Before You Program ......................................................................................................... 6
Install the Batteries.................................................................................................................... 6
Adaptive Intelligent Recovery™ Selection ............................................................................. 7
STEP 4 Program The Thermostat ................................................................................................. 9
STEP 5 Mount Thermostat Wallplate.......................................................................................... 16
STEP 6 Adjust System On-Time, Clock Display, as Required ................................................ 18
STEP 7 Adjust Fan Operation Switch, as Required.................................................................. 20
STEP 8 Wire Wallplate Terminals ............................................................................................... 21
STEP 9 Mount The Thermostat ................................................................................................... 24
STEP 10 Check Thermostat Operation After Programming and Installing ........................... 25
STEP 11 Set the Fan and System Switches .............................................................................. 28
Troubleshooting Guide ................................................................................................................ 30
Index............................................................................................................................................... 34
Limited One-Year Warranty ......................................................................................................... 36
2 69-0733—3
1
1
1

3 69-0733—3
■■Acquire tools and items as needed (below).
CROSS-RECESSED
SCREWDRIVER HAND OR POWER
DRILL WITH 3/16 INCH
DRILL BIT, IF NEEDED, TO
DRILL HOLES IN WALL
WIRE CUTTER/STRIPPER OR SHARP
KNIFE, IF NEEDED, TO STRIP WIRES MASKING TAPE, IF 
NEEDED, TO LABEL WIRES 
AS DISCONNECTED FROM
OLD THERMOSTAT
LEVEL, IF NEEDED, TO LEVEL
THERMOSTAT FOR APPEARANCE
M878B
4 69-0733—3
STEP 2 Remove OldThermostat
WIRES THROUGH
WALL OPENING
M5136
■■Test to make certain that your heating and
cooling systems are working properly. If either
does not work, contact your local heating/air
conditioningdealer.Toavoidcompressordam-
age, do not operate the cooling system when
outdoor temperature is below 50°F (10°C).
■■
Turn off power to system at the furnace, or
at the fuse/circuit breaker panel.
■■Carefully unpack your new thermostat and
wallplate;savepackageofscrews, instructions
and receipt.
■■Removethecoverfromtheoldthermostat.If
it does not snap off when pulled firmly from the
bottom, check for a screw used to lock on the
cover.
■■Loosen screws holding thermostat to sub-
base, wallplate or wall, and lift away.
■■Disconnect wires from old thermostat or
subbase. As you disconnect each wire, use
masking tape to label it with the old terminal
designation.Ifthereare
only two wires, they do
notneedtobelabeled.
Wrap wires around
pencil to keep them
from falling back into
the wall, as shown.
Replacing a clock thermostat that has C or
C1 clock terminals?
If you are replacing a Honeywell Chronotherm®
Thermostat, you may find one or two wires that
go to the C or C1 clock terminals on the
Chronotherm®Thermostat wiring wallplate. Do

5 69-0733—3
which programmable thermostats will work with
your system, call Honeywell Customer Assis-
tance at 1-800-468-1502.
Three thermostat wires?
If you have three wires for heating only and can
operate the fan using the fan ON switch, this
thermostatwillworkwithyoursystem.However,
some hot water (zoned) heating systems have
three thermostat wires. The thermostat will not
workwithoutinstallinganisolatingrelayonthese
systems. For details, call Honeywell Customer
Assistance at 1-800-468-1502.
notallowthemtotouch,oryoucandamageyour
transformer. Disconnect the wires and wrap
them separately using electrical tape;
do not
wrapthemtogether
.Placethewireswherethey
will not interfere with the operation of the new
thermostat.Recordthecolorsandterminaldes-
ignation labels of the remaining wires.
Six or more wires?
If there are six or more wires (excluding clock
wires attached to terminals), you most likely
have a variation of a heat pump or multistage
system. The thermostat is
not compatible with
such systems so return the product to the place
of purchase. If you would like information about
6 69-0733—3
STEP 3 BeforeYou Program
M2589
INSTALL 3 AA ALKALINE BATTERIES AS SHOWN, 
POSITIVE (+) TERMINALS TOWARD RIGHT.

BACK OF THERMOSTAT
Install the Batteries
IMPORTANT: Three AA alkaline batteries are
included with the thermostat. Batteries must
beinstalledfor programming andoperationof
the thermostat and heating/cooling system.
■■Install the batteries in back of the thermostat
as shown, making sure positive (+) terminals all
face toward the right.
As the batteries are running low, a REPL BAT
indicator will flash for 1 to 2 months before bat-
teries run out completely. Replace the batteries
as soon as possible after the indicator starts
flashing.
If you insert new batteries within 20 to 30 sec-
ondsofremoving the old ones, youwillnothave
to reprogram the thermostat. However, if the
display is blank, the batteries are dead or
incorrectly installed. In this case, you will
have toreprogram. See pages 13 through 15
to reprogram. If you do not reprogram, the
factory-prepro-
grammed
settings will be
in effect, as
shown in
chart on
pages 11
and 12.

7 69-0733—3
IMPORTANT: Although the thermostat has a
low battery indicator, replace the batteries
onceayeartopreventleakageandtoprevent
the thermostat and heating/cooling system
from shutting down due to lack of battery
power.
As a precaution when leaving home for longer
thanamonth,changebatteriesbeforeyouleave
topreventsystemfromshuttingdownduetolack
of battery power.
Use fresh alkaline batteries; nonalkaline bat-
teriesdonotlastaslong,andmayleak,causing
damage to the thermostat or the wall surface.
We recommend Energizer®batteries.
Adaptive Intelligent Recovery™
Selection
Before you program your thermostat, you must
decide if you want to leave the thermostat at
the factory-set Adaptive Intelligent Recovery™
setting, or adjust it to conventional recovery. If
youchooseconventionalrecovery,adjustscrew
3A(onthebackof thethermostat)byturning
out
one turn.
WithAdaptiveIntelligentRecovery™,yourhome
gradually reaches the comfort temperature you
set at the exact time programmed into the ther-
mostattoachievemaximumenergysavingsand
comfort.
8 69-0733—3
More about Adaptive Intelligent Recovery™…
for the thermostat to adjust to the weather, your
lifestyle, home construction and heating/cooling
system.
Withconventionalrecovery,theprogrammedtime
marks the start of the time your furnace or air
conditionercomesontostartrecovery;therefore,
you should program the start time to be earlier
than the desired comfort time. The best starting
time varies as the seasons change, but 30
minutes is a good head start time to use.
NOTE:Ifyouadjustscrew
3Aforconventionalre-
covery, a ■■indicator
appears in the lower
rightcornerofthether-
mostatdisplayasare-
minder that you are no longer using the Adap-
tive Intelligent Recovery™ feature.
PM
SET
PT
TUE
DAYTIME
INDICATES 
THERMOSTAT IS SET FOR 
CONVENTIONAL RECOVERY
M2483
This thermostat is actually a small but powerful
computer.Whencalculatingtheexacttimetoturn
onyourfurnaceorairconditioner,itconsiders:(1)
air temperature, (2) the temperature of
the wall and (3) when you want the comfort
temperature established.
During recovery, the thermostat increases the
controltemperaturegraduallyandturnstheequip-
ment on and off several times
before reaching
your comfort time to save energy by avoiding
overshooting the comfort temperature. You can
seethe current controltemperature anytime dur-
ing recovery by pressing the CURRENT SET-
TING key.
This smart control learns from experience. Each
day it checks how closely it hit the target and
adjusts the recovery start time accordingly. It
normallytakes
fourtoeightdaysafterinstallation

STEP 4 ProgramThe Thermostat
work or school. (This will be a higher tem-
peratureduring heating season, oralower
temperature during cooling season.)
DAYTIMEisthetimeperiodyoucansetforan
energy-saving temperature while you are
awayatworkorschool.(Thiswillbealower
temperature during heating season, or a
highertemperatureduringcoolingseason.)
EVENING is the time period you want the
house at a comfortable temperature for
activities before bedtime. (Again, higher
heat or lower cool.)
NIGHT is the time period you can set for an
energy-saving temperature while you are
sleeping.(Again,lowerheatorhighercool.
Although for more comfortable sleeping,
some people choose not to raise the cool
temperature during the night.)
10 69-0733—3
PROGRAMMING
After the batteries are installed, the thermostat
can be easily programmed in your hand before
it is installed on the wall.
If you would prefer to program the thermostat
after it is installed on the wall, skip to page 16,
and return later to this programming section.
The following personal programming chart
(pages 11 and 12) may be helpful when plan-
ning your program schedule of time and tem-
perature settings for various times of the day.
Four time periods are available—MORNING,
DAYTIME, EVENING and NIGHT. Each
period has its own setting key.
MORNING is the time period you want the
houseatacomfortabletemperature when
you get up and while you get ready for 9 69-0733—3
You will set one schedule for weekdays, one for
Saturday, and another for Sunday, because
your requirements will probably be different for
each.
Fill in the times and temperatures you desire for
weekdays, Saturday, Sunday. The factory-pre-
programmed time and temperature settings are
shown in parentheses. If you decide not to
program the thermostat, it automatically con-
trolstothesesettings.Thethermostatrequiresa
time and temperature program for the MORN-
ING period. You can program DAYTIME and
EVENING, or leave them blank. You can also
changeNIGHTorcancelit(seepage15),asyou
please.
Before programming, remove the clear plastic
overlay covering the display.
When pressing the keys, use the ball of your
fingeror a soft pencileraser.Useof sharp finger-
nails or pencil points can damage the keypad.
If at any time during programming you make an
error, just press the RUN PROGRAM key, and
continue again at the step where you left off.

Sunday Program
START HEATING COOLING
PERIOD TIME TEMPERATURE TEMPERATURE
MORNING _____________________ _____________________ _____________________
DAYTIME ______________ ______________ _____________
EVENING ______________ ______________ _____________
NIGHT _____________________ _____________________ _____________________
The temperatures cannot be set any higher than 88°F (31°C) or any lower than 45°F (7°C).
NOTE: The factory-preprogrammed time and temperature settings are shown in parentheses.
1
11 69-0733—3
(6:00 AM) (70°F [21°C]) (78°F [26°C])
(10:00 PM) (60°F [16°C]) (78°F [26°C])
11
(6:00 AM) (70°F [21°C]) (78°F [26°C])
(10:00 PM) (60°F [16°C]) (78°F [26°C])
Personal Programming Chart
Weekday Program
START HEATING COOLING
PERIOD TIME TEMPERATURE TEMPERATURE
MORNING _____________________ _____________________
DAYTIME ______________ ______________ _____________
EVENING ______________ ______________ _____________
NIGHT _____________________ _____________________ _____________________
Saturday Program
START HEATING COOLING
PERIOD TIME TEMPERATURE TEMPERATURE
MORNING _____________________ _____________________ _____________________
DAYTIME ______________ ______________ _____________
EVENING ______________ ______________ _____________
NIGHT _____________________ _____________________ _____________________
11
(6:00 AM) (70°F [21°C]) (78°F [26°C])
(10:00 PM) (60°F [16°C]) (78°F [26°C])
11
12 69-0733—3
PROGRAMMING

COOLING PROGRAM
Thetimesyousetforheatingremainthesameforcooling;youonlyneedtoprogramthetemperatures.
With system switch at COOL, press and release . Use atoprogramMon-Fri
MORNING temperature. Repeat using DAYTIME, EVENING, NIGHT keys.
For Saturday, press to SAT. Press and release ; use ato
program
Saturday morning temperature. Repeat using DAYTIME, EVENING, NIGHT keys.
For Sunday, press to SUN. Repeat steps as you did for SAT.
After programming, adjust fan and system switches as desired.
Press and release to start the program.
a Press on to move number back; press on to move number ahead.
Time
When programming your new thermostat, use this guide. Batteries are required for programming
and operation.
SET PRESENT DAY
Press and release then until present day shows.
SET PRESENT TIME
Press and release then until present time shows.
HEATING PROGRAM
With system switch at HEAT, press and release . Use and to
program Mon-Fri MORNING time and temperature. Repeat using DAYTIME, EVENING, NIGHT
keys.
For Saturday, press to SAT. Press and release ; use and
to program Saturday morning time and temperature. Repeat using DAYTIME, EVENING,
NIGHT keys.
For Sunday, press to SUN. Repeat steps as you did for SAT.
13 69-0733—3
Morning
Time
a
Temp
a
PROGRAMMING 14 69-0733—3
Temp
Morning
Time
Day
a
a
Day
Set
Present
Day/Time
Day
Set
Present
Day/Time
a
Morning
Temp
Day
Day
Run
Program
Morning
Temp

For operating or making changes, use this guide.
Temporarily Change temperature
for current period only — ; TEMPORARY indicator
shows on display, and cancels itself at next scheduled change. To cancel sooner, you may
press .
Hold a temperature indefinitely (such as on vacation)— , Hold appears
on display; to cancel, press .
Check current temperature setting— .
Cancel a program—Press and hold , or three seconds to cancel.
Morning cannot be cancelled (only changed).
Permanently Change a program—Repeat steps under Heating Program (page 13) or Cooling
Program (page 14), as applicable.
Return to normal program or start program— .
aPress on to move number back; press on to move number ahead.
a
INSTALLATION
16 69-0733—3
STEP 5 MountThermostat Wallplate
WIRES THROUGH
WALL OPENING
WALL
WALL
ANCHORS
(2)
WALLPLATE
MOUNTING
SCREWS (2)
M5932A
MOUNTING
HOLES (3) 1
1USE THE TWO MOUNTING HOLES THAT BEST FIT APPLICATION.
■■Position wallplate on wall. Level the wall-
plate for appearance only. Use a pencil to
mark the two mounting holes that best fit the
application.
15 69-0733—3
Run
Program
Temp
Hold
Temp
a
Run
Program
Daytime
Evening
Night
Current
Setting
Run
Program
Temp