Honeywell CT8602 User manual

Place Bar Code Here
69- 1532
OWNER’S GUIDE
® U.S. Registered Trademark
Copyright © 2001 Honeywell • •All Rights Reserved
Honeywell CT8602
PROGRAMMABLE THERMOSTAT
Seven Day
Programmable Heat and/or Cool
Low Voltage (20 to 30 Vac) Thermostat and Wallplate
Model CT8602
Para obtener un documento con las instrucciones en español, por favor visite nuestro sitio
de web a: www.honeywell.com/yourhome.
Pour obtenir des notices techniques en français, veuillez consulter notre site web
www.honeywell.com/yourhome.
Table of Contents
Step 1. Prepare for Installation .................................................................................................................................. 5
Step 2. Remove Old Thermostat ............................................................................................................................... 6
Step 3. Mount thermostat Wallplate ........................................................................................................................... 7
Step 4. Wire Wallplate Terminals ............................................................................................................................... 8
Step 5. Install the Batteries ........................................................................................................................................ 9
Step 6. Set Fan Operation Switch ............................................................................................................................. 10
Step 7. Mount the Thermostat ................................................................................................................................... 11
Step 8. Customize Your Thermostat .......................................................................................................................... 11
Step 9. Set the Clock ................................................................................................................................................. 13
Step 10. Programming ............................................................................................................................................... 14
Step 11. Operating Your Thermostat ......................................................................................................................... 17
Step 12. Set the Fan and System Switches .............................................................................................................. 19
If You Have a Problem ............................................................................................................................................... 19
Smart Response™ Technology ................................................................................................................................. 21
Wiring Diagrams ........................................................................................................................................................ 22

69-1532 2
Total comfort temperature management with Smart Response™
Technology.
Congratulations! You made a smart choice by purchasing your new Honeywell thermostat; the smart thermostat that;
•Keeps you comfortable by automatically calculating exactly when the furnace or air conditioning 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 automatically remembering to adjust the temperature when
you leave home or go to sleep.
•Provides the ultimate in comfort and convenience. It comes preprogrammed. You can use the preprogrammed
schedule, or set your own.
This manual answers many of the questions that can arise as you become familiar and comfortable with your
Honeywell thermostat — the state of the art in home comfort controls.
Read these instructions carefully. Failure to follow these instructions can damage the product or cause a hazardous
condition.
MERCURY NOTICE
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.
M10614
MERCUR
Y
SWITCH
T
YPICAL LOCATION OF A MERCURY
S
WITCH IN A THERMOSTAT

3 69-1532
M14880
Time Set Program
System
Fan
On Auto
Run
Program
Hold Temp
Set Current
Day/Time Wake Leave Return Sleep
Day Heat/Cool
Settings
Daylight
Time Copy
INCREASE TEMPERATURE
SETTING OR SCROLL
FORWARD THROUGH
INSTALLER SETUP OPTIONS
DECREASE TEMPERATURE
SETTING OR SCROLL
BACKWARD THROUGH
INSTALLER SETUP OPTION
S
DISPLAY INFORMATION
SUCH AS PRESENT
SETTINGS AND OUTDOOR
TEMPERATURE
RETURN TO
NORMAL
OPERATIONS
ENTER
INDEFINITE
OR TIMED
HOLD MODE
SET CURRENT
DAY AND TIME
SET CURRENT OR
PROGRAM DAY
CHANGE BETWEEN
DAYLIGHT SAVINGS
AND STANDARD TIME
I
NCREASE TIME SETTING
O
R SCROLL FORWARD
T
HROUGH INSTALLER SETUP
A
ND SYSTEM TEST
DECREASE TIME SETTING OR
SCROLL BACKWARD THROUGH
INSTALLER SETUP AND SYSTEM TEST
COPY ONE PROGRAMMED
DAY TO ANOTHER DAY
SET WAKE TIMES
AND SETPOINTS
CHANGE BETWEEN
HEATING AND COOLING
SETPOINTS
SET LEAVE TIMES
AND SETPOINTS SET RETURN TIMES
AND SETPOINTS
SET SLEEP TIMES
AND SETPOINTS
SYSTEM SWITCH
FAN SWITCH
Off CoolHeat

69-1532 4
Mon
Wake Leave Return Sleep Room
Wait
System
Heat
Off
Cool
AM
Hold for
Repl Batt
Recovery
DST
Tue Wed Thu Fri Sat Sun
Days
Temporary Setting
Set Program Set Day/Time
Filter
DISPLAYS EITHER CURRENT
TIME OF DAY OR PROGRAM TIMES
SHOWS TEMPERATURE SETTING
CHANGED FOR THIS PROGRAM PERIOD
SHOWS THE TEMPERATURE
DISPLAYED IS THE CURRENT
SET TEMPERATURE
SHOWS THE TEMPERATURE
DISPLAYED IS THE CURRENT
ROOM TEMPERATURE
SHOWS THE BATTERIES
ARE LOW AND MUST BE
REPLACED
DISPLAYS
EITHER ROOM
OR SET
TEMPERATURES
SHOWS SMART
RESPONSE IS OFF
.
CONVENTIONAL
RECOVERY IS ON
S
HOWS SMART
R
ESPONSE
I
S CHANGING
T
HE TEMPERATURE
T
O MEET THE
C
URRENT
P
ROGRAMS
SHOWS THAT
THERMOSTAT IS
"CALLING" FOR
HEAT OR COOL
SHOWS CURRENT
SYSTEM SWITCH
POSITION
HEAT/OFF/COOL
SHOWS CURRENT
PROGRAM PERIOD
OR PERIOD BEING
PROGRAMMED
SHOWS CURRENT
DAY OR DAYS
BEING
PROGRAMMED
SHOWS
VACATION
HOLD
DURATION
SHOWS WHEN THERMOSTAT IS
IN THE PROGRAMMING MODE
SHOWS SYSTEM ON
DAYLIGHT SAVINGS TIME
S
HOWS THERMOSTAT IS
P
ROCESSING INFORMATION
A
ND WAITING TO CALL FOR
H
EAT OR COOL
M18746

5 69-1532
STEP 1. PREPARE FOR INSTALLATION
❑Check Table 1, the compatibility chart, to make sure the thermostat is compatible with your system. If your system
is not compatible, call Honeywell Customer Relations Center, toll-free, 1-800-468-1502.
Table 1. Compatibility Chart.
aCompatible with 2-wire Honeywell and Taco zone valves. Not compatible with 3-wire zone valves or 2-wire White
Rodgers no. 1361 zone valves.
bMillivolt system must be heat only.
cNot compatible with any 120/240 volt system.
Package Contents
• Thermostat • Wallplate • Screws and anchors
• Wiring labels • 3 Energizer® AA batteries • Owners manual
Tools Required
• Screwdriver
• Drill
System Type Compatibility with CT8602
Gas — Standing Pilot Yes
Gas — Electronic Ignition Yes
Gas-fired Boilers Yesa
Gas —750 Millivolt Heat onlybYes
Oil-Fired Boilers Yesa
Oil-Fired Furnace Yes
Electric Furnace Yes
Electric Air Conditioning Yes
Baseboard Electric (120/240 line volt)cNo
Single Stage Heat Pump Yes
Multistage Heat Pumps/Multistage Equipment No

669-1532
STEP 2. REMOVE OLD THERMOSTAT
❑Test your heating and cooling systems to make sure they work properly. If either system does not work, contact
your local heating/air-conditioning dealer. To avoid compressor damage, do not operate the cooling system when
outdoor temperature is below 50°F (10°C).
❑Turn off power to the system at the furnace or the fuse/circuit breaker panel.
❑Carefully unpack your new thermostat and wallplate. Save package of screws, instructions, and receipt.
❑Remove the cover from the old thermostat. If the cover does not snap off when pulled firmly from the bottom, check
for a screw or screws used to lock on the cover.
❑Loosen the screw or screws holding the thermostat to the wallplate and lift the thermostat away.
❑Disconnect the wires from the old thermostat. As you disconnect each wire, attach the enclosed labels with the old
terminal designation. If there are only two wires, they do not need to be labeled. Wrap the wires around a pencil as
shown to keep them from falling back into the wall.
Special Installations
Read this section if you are replacing:
• Clock thermostat with separate wires for the clock.
• Thermostat with six or more wires connected to it.
• Thermostat in a heating only system with three wires.
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 going to the C or C1 clock
terminals on the Chronotherm wiring wallplate. Do not allow them to touch, or you can damage the transformer.
Disconnect the wires and wrap them separately using electrical tape. Do not wrap them together. Place the wires
where they will not interfere with the operation of the new thermostat. Record the colors and terminal designation
labels of the remaining wires.
Replacing a Thermostat that has Six or More Wires
If there are six or more wires (excluding clock wires attached to terminals), you probably have a variation of a
multistage heat pump or other multistage system. This thermostat is not compatible with multistage systems, so return
the product to the place of purchase. If you have questions regarding this thermostat please visit our web site at
www.honeywell.com/yourhome, or call the 24-hour automated information line at 1-800-468-1502.
Replacing a Thermostat that has Three Wires
If you have three wires for a heating only system and can operate the fan using the fan ON switch this thermostat works
with your system. However, some hot water (zoned) heating systems also have three wires. Your thermostat will work
only if you install an isolating relay on these systems. For details, call your local heating and/or cooling contractor.
WIRES THROUG
H
WALL OPENING
M5136

7 69-1532
STEP 3. MOUNT THERMOSTAT WALLPLATE
❑Separate the wallplate from the thermostat by placing your thumb or fingers
between the bottom of the wallplate and the thermostat, and pulling the
wallplate up and away from the thermostat. See illustration at right.
❑Position the wallplate on the wall. Level the wallplate for appearance if desired.
Use a pencil to mark the two mounting holes that best fit the application.
❑Remove the wallplate from the wall. Drill two 3/16 in. holes in wall (if drywall) as
shown. For materials such as plaster or wood, drill 7/32 in. holes where marked.
Gently, tap the (provided) anchors into the drilled holes until they are flush with
the wall.
❑Reposition the wallplate over the holes. Pull the wires through the wiring
opening. Loosely insert mounting screws into each of the holes.
❑Level the wallplate if desired. Thermostat functions properly when not level.
❑Tighten mounting screws.
M16427
WIRES
THROUGH WALL
WALL
MOUNTING
HOLES
M15044
MOUNTING
SCREWS
WALL
ANCHORS (2)

69-1532 8
STEP 4. WIRE WALLPLATE TERMINALS
IMPORTANT
All wiring must comply with local codes and ordinances. If
unsure about household wiring procedures, call your local heat-
ing/air-conditioning contractor.
Refer to the labels you placed on the wires when you removed the old
thermostat (see illustration).
❑Match the letter of your old thermostat wire with the corresponding
terminal letter on your new thermostat. Refer to Table 2.
❑Remove the factory-installed jumper connecting terminals R and RC if
wires are connected to both of those terminals.
❑For wiring diagrams, if needed, see pp 22-23.
❑Loosen the terminal screws. Slip each wire beneath its matching
terminal. Wraparound and straight connections are both acceptable,
(see illustration). Tighten the terminals.
❑Plug the hole in the wall with insulation to help prevent drafts from adversely affecting thermostat operation.
M16425
R
W
Y
G
M482
6
F
OR WRAPAROUND
I
NSERTION STRIP
7
/16 IN. (11 MM).
FOR STRAIGHT INSERTION
STRIP 5/16 IN. (8 MM).

9 69-1532
Table 2. Terminal Designations on Old and New Thermostats
aIf both RH and R terminals are present on existing thermostat, remove jumper and connect Rh to R and R to Rc.
bDo not connect both O and B when wiring to a single stage heat pump. Connect O to O. Tape off B.
cTape off end of the wire with electrical tape and push the taped wire back into the wiring hole in the wall.
STEP 5. INSTALL THE BATTERIES
IMPORTANT
Three AA alkaline batteries are included with the thermo-
stat. Batteries must be installed for programming and opera-
tion of the thermostat and the heating/cooling system.
❑Install the batteries in the wallplate so the positive terminals all
point up (see illustration).
❑If the thermostat is already mounted on the wall, remove the
thermostat by placing your thumb between the thermostat and
wallplate and pulling the thermostat up and away as shown.
Terminal on Old Thermostat Connect To Description
R, RHa, 4, V R Power
Rc, RaRc Power for cooling
W, W1, H W Heat
Y, Y 1, M Y Cooling
G, F G Fan
O O Changeover in cool. (Single stage heat pump only).
BbBbChangeover in heat. (Single stage heat pump only).
Cc, Xc, BbDo not connect. Transformer common
W2, H2Do not continue installation.
Call 1-800-468-1502.
Second stage heat.
Y2Second stage cool.
M1062
2
INSTALL 3 AA ALKALINE BATTERIES
AS SHOWN, POSITIVE (+) TERMINALS
TOWARD TOP.
WALLPLATE
B
RRCOWYG

69-1532 10
When the batteries are running low, a REPL BAT message flashes for one to
two months before the batteries run out completely. Replace the batteries as
soon as possible once the message flashes.
IMPORTANT
Although the thermostat has a low battery indicator, replace the
batteries once per year to prevent leakage and to prevent the ther-
mostat and heating/cooling system from shutting down due to lack
of battery power in the thermostat.
If you insert new batteries within 20 to 30 seconds of removing the old
batteries, the system retains the current time and day. If the display is blank,
the batteries are dead or installed incorrectly. You must reset the time and
day. Refer to Set the Clock for instructions.
As a precaution when leaving home for longer than a month, change batteries before leaving to prevent
the system from shutting down due to lack of power. Always use fresh alkaline batteries. Nonalkaline
batteries do not last as long. They also can leak, causing damage to the thermostat and the wall surface.
Honeywell recommends Energizer® batteries.
STEP 6. SET FAN OPERATION SWITCH
The thermostat fan operation switch, labeled FUEL SWITCH is factory
set in the F position. This is the correct setting for most systems. If your
system is an electric heat system, set the switch to E. The E setting
allows the fan to turn on immediately with the heating and cooling in a
system where the G terminal is connected.
M16424
80
90
70
60
90
80
70
60
M1267
6
FUEL SWITCH

11 69-1532
STEP 7. MOUNT THE THERMOSTAT
STEP 8. CUSTOMIZE YOUR THERMOSTAT
Your Honeywell CT8602 thermostat comes preset to the most commonly used settings. The settings are:
Gas or oil forced air furnace.
Smart Response technology on.
Temperature °F.
12-hour clock format.
You can change any or all of these settings.
IMPORTANT
Always press the keys with your fingertip or a similar blunt tool. Sharp instruments like pens and pencil
points can damage the keyboard.
A
. ENGAGE TABS AT TOP
O
F THERMOSTAT
A
ND WALLPLATE.
M12703
B
. PRESS LOWER
E
DGE OF CASE
T
O LATCH.

69-1532 12
❑Press and hold down , , and , simultaneously until the screen shows.
You now can change any of these settings.
System Type (Feature Number 4)
System type options are:
1 = Gravity or steam system.
3 = Hot water, high efficiency furnace (90% or better), or single stage heat pump.
6 = Gas or oil forced air furnace (preset).
9 = Electric furnace.
To change your system type:
❑Press until display shows your furnace or boiler type.
❑Press Time to move to next feature or to return to main display.
Smart Response™ Technology (Feature Number 13)
Smart Response technology options are:
0 = Smart Response technology on (preset).
1 = Smart Response technology off.
To turn Smart Response technology on or off:
❑Press once.
❑Press Time to move to next feature or to return to main display.
NOTE: See Smart Response technology (page 21) for information about this feature.
Temperature Format (Feature Number 14)
Temperature format options are:
0 = °F (preset).
1 = °C.
To change temperature format:
❑Press once.
❑Press Time to move to next feature or to return to main display.
M1875
0
FEATURE
NUMBER OPTION
Run
Program
M1875
1
Run
Program
M1875
2
Run
Program

13 69-1532
Time Format (Feature Number 16)
Time format options are:
0 = 12-hour clock (preset).
1 = 24-hour clock.
To change time format:
❑Press once.
❑Press to return to main display.
Heating Temperature Range Stops (Feature Number 34)
Temperature range options are:
90 = highest setting for heating setpoint (preset)
40 to 89 = temperature range (1°F increments) heating setpoint can be set to.
Cooling Temperature Range Stops (Feature Number 35)
Temperature range options are:
45 = lowest setting for cooling setpoint (preset)
46 to 99 = temperature range (1°F increments) cooling setpoint can be set to.
Factory Set Function (Feature Number 37)
Do not change this setting.
STEP 9. SET THE CLOCK
Set Current Day and Time
NOTE: On initial power-up, the screen flashes 1:00 pm until you press a key.
❑Press .
❑Press until screen shows current day.
❑Press Time or until screen shows current time. (Tapping the will advance the time in one
hour increments).
M1875
3
Run
Program
M1874
8
M18749
M1875
4
Set Curren
t
Day/Time
Day
Set Curren
t
Day/Time

69-1532 14
❑Press until “DST” displays if daylight savings time is in effect.
❑Press .
STEP 10. PROGRAMMING
The keyboard is located behind the thermostat cover. The three most frequently used keys are near the display.
Pressing displays the current temperature settings. Pressing the and keys change the temperature. The
thermostat displays day, time, program period, temperature, system and fan settings.
There is an individual key for each of the four program periods:
—The program period when you want the house at a comfortable temperature when you get up and while you
get ready for work or school. (This is a higher temperature during the heating season and a lower
temperature during the cooling season).
—The program period you can set for an energy-saving temperature while you are away at work or school.
(This is a lower temperature during the heating season and a higher temperature during the cooling
season).
—The program period when you want the house at a comfortable temperature for activities before bedtime.
(This is a higher temperature during the heating season and a lower temperature during the cooling
season).
—The program period you can set for an energy-saving temperature while you sleeping. (This is a lower
temperature during the heating season and a higher temperature during the cooling season).
Daylight
Time
Run
Program
Wake
Leave
Return
Sleep

15 69-1532
Table 3 can be helpful when planning your schedule of time and temperature settings. The thermostat default settings
are shown in parentheses ( ).
Table 3. Personal Programming Table.
a Your heating setpoints cannot be higher than 90°F (32°C) or lower than 40°F (4.5°C).
bYour cooling setpoints cannot be higher than 99°F (37°C) or lower than 45°F (7°C).
Program the First Day
Start by programming the wake time and temperature for one day.
❑Press and release .
❑Press until the desired day displays. (Mon, Tue, Wed, Thu, Fri, Sat, Sun)
❑Press time or until the desired time shows in the display.
Period Default Setting
Monday
(Mon)
Tuesday
(Tue)
Wednesday
(Wed)
Thursday
(Thu)
Friday
(Fri)
Saturday
(Sat)
Sunday
(Sun)
Wake Time (6:00AM)
Heata(70°F/21°C)
Coolb(78°F/25.5°C)
Leave Time (8:00AM)
Heata(62°F/16.5°C)
Coolb(85°F/29.5°C)
Return Time (6:00PM)
Heata(70°F/21°C)
Coolb(78°F/25.5°C)
Sleep Time (10:00PM)
Heata(62°F/16.5°C)
Coolb(82°F/28°C)
Wake
Day

69-1532 16
NOTE: Program times are in 15 minute intervals. For example, 8:00, 8:15, 8:30.
❑Press or until the desired wake temperature displays.
The setpoint temperature range is 40°F to 90°F (4.5°C to 32°C) for heating and 45°F to 99°F (7°C to 37°C) for cooling.
❑Press to switch between setpoints.
NOTE: Program times are the same for heating and cooling.
❑Press or until the display shows the desired temperature setpoint.
❑Press , or and repeat these steps for each program period. The First Day is now
programmed.
❑Repeat each step in Program the First Day for the rest of the week.
NOTE: After the first day is programmed, you can copy that day to any other day using procedure in Copy a Day.
❑Press when the entire week is programmed.
Copy a Day
Your thermostat can copy program settings from one day to another.
❑Press , , or to enter programming mode.
❑Press until the display shows the day you want to copy.
❑Press . The display shows.
Heat/Cool
Settings
Leave Return
Sleep
Run
Program
Wake Leave Return
Sleep
Day
M13327
Mon
Copy

17 69-1532
❑Press until the display shows the day you want to copy to.
❑Press to accept the change.
❑Repeat these steps for each day you want to copy.
NOTE: donE appears for two seconds and then the normal program display appears.
Clear a Program Period
NOTE: Wake cannot be cleared.
❑Press , , or for the program period you want to clear.
❑Press until the desired day displays.
❑Press and hold the , , or for approximately 3 seconds until the time and temperature clear.
❑Repeat the above steps for each period to be cleared.
❑Press .
STEP 11. OPERATING YOUR THERMOSTAT
Change Temperature Setting Until the Next Program Period (Temporary Change)
❑Press or until the screen shows the desired temperature setting.
NOTE: The temporary temperature setting is displayed for about 3 seconds and then the room temperature is dis-
played. Temporary appears in the display. The setting cancels when the next program period starts or when
you press .
M13328
Mon Wed
Day
M1332
9
Copy
Leave Return Sleep
Day
Leave Return Sleep
Run
Program
Run
Program

69-1532 18
Change Temperature Setting Indefinitely (Hold)
❑Move the System switch to the desired position (Heat or Cool).
❑Press then or to change your setting if desired. (The display changes from showing the setpoint
temperature to room temperature after approximately three seconds).
❑To cancel “Hold” press .
Change the Temperature Setting Until a Designated Day and Period (Vacation Hold)
❑Press twice.
❑Press or until the display shows the desired temperature setpoint.
❑Press Time until the desired number of days that you will be away (1 through 255) is displayed.
❑Press , , or to select the program period when you want the program to restart.
NOTE: If the Vacation Hold needs to be cancelled before the designated time, press to return to the
program.
Daylight Savings Time Key
This feature allows you to switch between standard time and daylight savings time.
❑Press during fall to set the time back one hour.
❑Press during the spring to set time forward one hour. DST is displayed when operating on daylight savings
time.
NOTE: Pressing the Daylight Time key more than once in a five minute period scrolls you through various time
option. For example, one hour earlier or later, with or without DST. Pressing Daylight Time six times in a five
minute period returns you to your original setting.
Hold Temp
Run
Program
Hold Temp
Wake Leave Return Sleep
Run
Program
Daylight
Time
Daylight
Time

19 69-1532
STEP 12. SET THE FAN AND SYSTEM SWITCHES
IF YOU HAVE A PROBLEM
First set the fan switch. Fan On: The fan runs continuously. Use for improved air
circulation or for more efficient central air cleaning. (In a
heat-only system, fan runs continuously only if fan relay is
connected to the G thermostat terminal).
Fan Auto: Normal setting for most homes. The equipment
controls the fan operation.
Then set the system
switch.
Heat: The thermostat controls your heating system.
Off: Both the heating and air conditioning systems are off.
Cool: The thermostat controls your air conditioning system.
Table 4. Solution Guide.
If... Then…
Display does not appear. •Make sure the batteries are installed correctly.
•Make sure the thermostat is mounted and latched on the wallplate.
Mount and latch the thermostat on the wallplate if it is not.
Temperature settings will not change
(example; cannot set the heating higher
or the cooling lower).
•Make sure the temperature setpoints are:
40 to 90°F (4.5 to 32°C) for heating.
45 to 99°F (7 to 37°C) for cooling.
•Check Customize Your Thermostat section feature numbers 34 and 35.
Reset as necessary.
F
an
On Au
to
F
an
On Aut
o
S
ystem
Heat Off Co
ol
S
ystem
Heat Off Coo
l
S
ystem
Heat Off Co
ol

69-1532 20
Heating does not come on. •Make sure the heating setpoint is above the room temperature.
•Make sure the circuit breaker is not tripped, and reset it if necessary.
•Make sure the power switch at the equipment is in the On position, and
set it to On if it is in the Off position.
•Wait five minutes for the system to respond.
•Set the system switch to Heat.
Cooling does not come on. •Make sure the cooling setpoint is below the room temperature.
•Make sure the circuit breaker is not tripped, and reset it if necessary.
•Make sure the system switch at the air conditioner is in the On position,
and set it to On if it is in the Off position.
•Wait five minutes for the system to respond.
•Set the system switch to Cool.
System on indicator( = heat, =
cool) is lit, but no warm or cool air is
coming from the registers.
Wait five minutes after seeing the flame or snowflake and check the
registers again. If no there is no hot or cool air coming from the registers,
refer to Heating does not come on or Cooling does not come on. If all of this
has been checked, contact your local heating and cooling contractor.
Display flashes during programming. The temperature setting limit has been reached. The heating setting range
is 40°F to 90°F (4.5°C to 32°C). The cooling setting range is 45°F to 99°F
(7°C to 37°C).
Temperature change occurs at the
wrong times.
1. Check the program times for the period in question.
2. Make sure the AM and PM settings are correct.
3. Make sure the current time and day settings are correct.
4. Reprogram any incorrect settings.
NOTE: If your thermostat is set for Smart Response™ technology, the
start times occur before your programmed comfort periods.
Thermostat backlight appears dim. •Wait until Replace Battery indicator is illuminated and replace batteries.
•Replace batteries now.
Table 4. Solution Guide.
If... Then…