Honeywell ComfortNET CTK04 User guide

ComfortNet™ CTK04 Communicating Thermostat
With wireless accessories
System
Installation
Guide
Modulating control for up to 4 Heat/2 Cool communicating heat pump systems or up to
3 Heat/2 Cool communicating gas heat, electric cooling systems for residential and
commercial applications.
Installation guide for:
Quick start guide
• ComfortNet CTK04
Communicating Thermostat
• Portable Comfort Control
• Wireless Outdoor Sensor
• Wireless Indoor Sensor
• RedLINK™Internet Gateway
• Entry/Exit Remote
• Vent Boost Remote
1Install thermostat ..........................................................page 4
2Power optional accessories ...................................................7
3Setup thermostat ...................................................................8
4Link optional accessories ......................................................9
5Mount optional accessories................................................. 11
6Installer options ...................................................................12
ComfortNet™ User Menu.................................................... 13
Device replacement and specifications ..........................21-23
DISCONNECT POWER BEFORE INSTALLATION. Can cause electrical shock or equipment damage.
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 the Thermostat Recycling Corporation at www.thermostat-recycle.org or 800-238-8192 for information on how and
where to properly and safely dispose of your old thermostat.
Must be installed by a trained, experienced technician. Read these instructions carefully. Failure to follow these
instructions can damage the product or cause a hazardous condition.
I/O-CHTSTAT03
69-2688-11

System Installation Guide
2
69-2688—11 I/O-CHTSTAT03
The ComfortNet advantage
The premium Honeywell ComfortNet™ control system is easy to use, energy-effi-
cient, reliable and ensures the system is set up properly. Advanced operating algo-
rithms built into the control delivers efficient equipment operation while providing eco-
nomical comfort. The Honeywell ComfortNet Communicating thermostat is designed
to regulate and communicate with the central heating and cooling equipment and has
the ability to share information so the user will enjoy efficient, economical comfort
throughout the home.
RedLINK™ Compatible
RedLINK accessories include the Wireless Outdoor Sensor, Portable Comfort Control
(PCC), RedLINK Internet Gateway, Wireless Indoor Sensor, TrueSTEAM™ humidifier
with Wireless Adapter, Vent Boost Remote and Entry/Exit Remote.
Customizable Service Reminders
Set up to 10 service reminders. Choose from pre-set options or customize your own.
Pre-set reminder options include filter replacement, humidifier maintenance, dehu-
midifier filter, ventilator filter, UV bulb replacement, annual service, spring service,
fall service and warranty expiring soon. Reminders based on the date or outdoor
temperature will be displayed on the thermostat's main screen along with pre-set or
custom instructions.
User Interactions Log
The interaction log stores history of thermostat setting changes including tempera-
ture, system and installer setup. You can use the interaction log to save time by
determining if the issue is a system error or an accidental user error.
Configurable for Residential and Light Commercial Applications
One thermostat does it all to meet the needs of Residential and Light Commercial
applications. Simply select Residential or Commercial during the installer setup. If
Commercial is selected, the thermostat will use commercial language, meet building
codes and offer 365 day holiday scheduling.
USB Port
Visit http://thermostatsetup.honeywell.com to enter your dealer information and save
to a USB stick. Then load your dealer information and logo to multiple thermostats.
After setting up a thermostat, save Installer Setup, Holiday / Event Scheduler and
Custom Reminders to a USB stick. Then load this information to multiple thermostats.
To use the USB port, insert a USB stick in the bottom of the thermostat. Then select
the item you would like to load or save.
Selectable Sensors
When paired with a Wireless Indoor Sensor(s) you have the ability to choose which
sensor(s) to use for temperature, humidification and dehumidification. They can be
used in combination for temperature averaging—or individually—to condition humidity
levels in separate spaces.

CTK04 ComfortNet™ Communicating Thermostat
3I/O-CHTSTAT03 69-2688—11
Installation
This booklet contains installation instructions and information on the thermostat and
wireless accessories. Separate installation instructions for the furnace or air handler
and outdoor AC condensing unit or heat pump are provided with the appropriate
equipment. This thermostat is designed exclusively for use with the ComfortNet com-
municating system.
Valid System Configurations
This control may only be used with certain system configurations. Valid system con-
figurations for which this control can be used are:
• A communicating air handler matched with a communicating outdoor AC
condensing unit.
• A communicating air handler matched with a communicating outdoor heat pump
unit.
• A communicating furnace matched with a communicating outdoor AC condensing
unit.
• A communicating furnace matched with a communicating outdoor heat pump unit.
• A communicating furnace matched with a non-communicating single stage AC
condensing unit.
Installing Thermostat
1. Remove and inventory all ComfortNet components. The CTK04 contains the ComfortNet commu-
nicating thermostat, lithium coin cell battery, wall mounting screws and anchors, system installa-
tion guide, operating manual, transformer and a wiring set that includes two terminal blocks, two
sheet metal screws and wires.
2. Carefully separate the thermostat body from the thermostat base.
3. Place base at installation location and mark mounting hole locations on wall using base as a
template. See Thermostat Mounting section on next page for optimal mounting location.
4. Drill mounting holes. Drill 3/16" holes for drywall and 7/32" holes for plaster.
5. Attach base firmly to wall using two mounting screws. Leveling is for appearance only and will
not affect thermostat operation.
6. Connect wires to terminal block on base.
7. 18 AWG solid wire is recommended.
8. Push excess wire into wall and plug hole with a fire resistant material (such as fiberglass insula-
tion) to prevent drafts from affecting thermostat operation.
9. Insert coin cell battery in the back of the thermostat.
10. Carefully line up the thermostat with the base and snap into place.
HIGH
VOLTAGE
TRANSFORMER LOW
VOLTAGE CONNECTED
TO R AND C
TERMINALS
CONNECT 2-WIRES TO
INDOOR UNIT
REMOVE AND INVENTORY ALL
COMFORTNET™COMPONENTS
REMOVE OUTDOOR UNIT
COVER AND 7-PIN
CONNECTOR
NOTE: THE CTK04 CONTAINS THE THERMOSTAT, LITHIUM COIN CELL BATTERY,
WALL MOUNTING SCREWS AND ANCHORS, SYSTEM INSTALLATION GUIDE,
OPERATING MANUAL, TRANSFORMER AND A WIRING SET THAT INCLUDES
TWO TERMINAL BLOCKS AND WIRES.
P/N F0430675005
INSTALL HVAC COMPONENTS
GAS
FURNACE
AIR
HANDLER
TERMINALS 1 & 2 ARE
COMMUNICATIONS
WIRES. THEY SHOULD
NEVER BE CONNECTED
TO THE 24 VAC R&C
POWER SUPPLY
TERMINALS.
CONNECT 4-WIRES
FROM STAT AND
2 WIRES FROM
OUTDOOR UNIT
P/N F0430679005
P/N F0430673005
CONNECT TO THE OUTDOOR UNIT
2-WIRE/TRANSFORMER
CONNECTION
CONNECT HIGH VOLTAGE TRANSFORMER LEADS TO L1
AND L2 MALE SPADE TERMINALS ON CIRCUIT BOARD.
DO NOT CONNECT R AND C BETWEEN THE INDOOR UNIT
AND OUTDOOR UNIT. SEE PAGE 5.
INSTALL THERMOSTAT ON INTERIOR WALL
M33487C
1REMOVE 9-PIN CONNECTOR
FROM FURNACE OR AIR
HANDLER CONTROL
23
4
56
AIR CONDITIONER
OR HEAT PUMP
AIR CONDITIONER
OR HEAT PUMP
TRANSFORMER
ADDITIONAL TRANSFORMER
IS NOT REQUIRED FOR
INVERTER/VARIABLE SPEED
OUTDOOR COMMUNICATING
UNITS.
ADDITIONAL TRANSFORMER
IS REQUIRED FOR 2-STAGE
OUTDOOR COMMUNICATING
UNITS.
LOW (24 VAC)
VOLTAGE

System Installation Guide
4
69-2688—11 I/O-CHTSTAT03
Install thermostat
1
Thermostat Mounting
Mount the thermostat approximately 5 feet from the floor on an interior wall using the
included screws and anchors. Drill 3/16" holes for drywall and 7/32" holes for plaster.
Do not install the thermostat where it can be affected by:
• Drafts or dead spots behind doors and in corners.
• Hot or cold air from ducts.
• Radiant heat from sun or appliances.
• Concealed pipes and chimneys.
• Unheated (uncooled) areas such as an outside wall.
Terminal Functions:
1 - Data 1
2 - Data 2
R - 24 volt power
C - 24 volt common
Wire Gauge:
18 gauge wire is recommended. Maximum wire distance between the ComfortNet
thermostat and the IFC should not exceed 100 feet using 18 gauge wire.
MCR29241
MCR33170
1
2
R
C
MCR33171
1
2
R
C

CTK04 ComfortNet™ Communicating Thermostat
5I/O-CHTSTAT03 69-2688—11
Install thermostat
1
Wiring Thermostat, Indoor Unit and Outdoor Unit
Wire Thermostat to Indoor Unit
Connect 1, 2, R and C from the thermostat to 1, 2, R and C at the Indoor Unit.
Wire Outdoor Unit
Connect wires 1 and 2 from the Indoor Unit to 1 and 2 at the Outdoor Unit. Install the
transformer provided and connect to R and C at the Outdoor Unit. (NOTE: installing
the additional transformer is NOT required for inverter/variable speed outdoor com-
municating units. Additional transformer IS required for 2-stage outdoor communicat-
ing units.) Do NOT connect R and C between the Indoor Unit and Outdoor Unit. See
below.
CTK04
INDOOR
BOARD TERMINAL
CONNECTIONS
R
C
1
2
24VAC (HOT)
24VAC
(COMMON)
DATA 1
DATA 2
L1
L2
24VAC 240V
OUTDOOR
BOARD TERMINAL
CONNECTIONS
OUTDOOR
TRANSFORMER
INSTALLING THE ADDITIONAL TRANSFORMER IS NOT REQUIRED FOR INVERTER/VARIABLE
SPEED OUTDOOR COMMUNICATING UNITS. ADDITIONAL TRANSFORMER IS REQUIRED FOR
2-STAGE OUTDOOR COMMUNICATING UNITS.
R
C
1
2
R
C
1
2
M33168C
1
1

System Installation Guide
6
69-2688—11 I/O-CHTSTAT03
M3294
0
[If no wireless accessories are used, skip to Section 3.]
Portable Comfort Control
Install 2 fresh AAA alkaline batteries Install 3 fresh AA alkaline batteries
Outdoor air sensor Indoor air sensor
Install 2 fresh AA lithium batteries
Power optional accessories
2
The Honeywell RedLINK Internet Gateway gives your customers remote access to
home climate-control systems from any location with Internet access.
Using a Web browser, users can review and adjust indoor temperature,
system mode and other settings. The Gateway can also send alerts to as many as 6
email addresses if a problem occurs.
RedLINK™Internet Gateway
Connect power cord to
an electrical outlet not
controlled by a wall switch
Connect RedLINK Gateway to a
router or modem with Ethernet
cable (RJ45).
MCR32937
MCR32938
MCR32939

CTK04 ComfortNet™ Communicating Thermostat
7I/O-CHTSTAT03 69-2688—11
Power optional accessories
2
TrueSTEAM
Connect the ABCD terminals between TrueSTEAM and the THM4000 Wireless
Adapter.
Adjust the DIP Switches on TrueSTEAM as follows when using the Wireless Adapter:
DIP3: UP
DIP4: UP
DIP5: DOWN THM4000R1000
Tr ueSTEAM
MCR31476
6
543
2
ON
OFF
1
Entry/Exit Remote or Vent Boost Remote
1 Remove the cover.
2 Insert the CR2450 coin cell battery (included) into
the slot at the bottom of the remote. See polarity
marking on the remote.
3 The LED will briefly flash green. If it flashes red,
battery is not good.
MCR33269

System Installation Guide
8
69-2688—11 I/O-CHTSTAT03
Setup thermostat
3
Initial Power Up
1 Turn on AC power to the system.
2 Select Language. Press Next.
3 Select Application (Residential or
Commercial). Press Next.
The thermostat will identify the number
of units connected and then prompt
the installer to select the equipment
(Furnace or Air Handler, Heat Pump or
Air Conditioner) installed. Once config-
ured, the installer will be prompted to
add RedLINK accessories (page 9) and
setup the Installer Options (page 12).
4 Enter a Device Name. Press Next.

CTK04 ComfortNet™ Communicating Thermostat
9I/O-CHTSTAT03 69-2688—11
MCR32935
MCR32934
While the Add Device screen is displayed
on the thermostat, press and release the
CONNECT button on each wireless device, as
described below. Accessories need to be at
least 2 feet away from the thermostat during
the linking process.
If you need to return to the "Add Device" screen to add devices later, press MENU
and scroll down to press INSTALLER OPTIONS. Enter the date code (password) when
prompted. The date code is printed on the back of the thermostat; or press MENU >
EQUIPMENT STATUS to find the date code. After you enter the password, scroll down to
press WIRELESS DEVICE MANAGER and then select ADD DEVICE.
MCR28847A
Link optional accessories to wireless network
4
Wireless outdoor sensor
Wireless indoor sensor
Press and release CONNECT. After
a short delay the thermostat will
display "Wireless Outdoor Sensor
added" on the Add Device screen.
Press and release CONNECT.
After a short delay, the status light
will glow green for 15 seconds.
If the status light turns red, the sensor did not link with the thermostat.
Battery level indicators (when batteries are inserted)
Good: Status light flashes green for 5 seconds.
Low: Status light flashes red for 5 seconds. Use fresh batteries.
Battery level indicators (during use)
Good: Status light remains off.
Low: Battery power will be depleted in about 2 months. Thermostat displays Low
Battery warning. Status light remains off.
Critical: Battery power will be depleted in about 2–3 weeks. Status light flashes red.
Press DONE after all devices have been linked
When power is interrupted, the equipment and the RedLINK
accessories will automatically restore communication after power
resumes.
If you have both a wired and wireless outdoor sensor installed, the
thermostat displays the reading from the wireless outdoor sensor.
The thermostat can use up to 6 optional
wireless sensors.

System Installation Guide
10
69-2688—11 I/O-CHTSTAT03
Entry/Exit Remote or Vent Boost Remote
Press and release CONNECT button.
TrueSTEAM
Press and release the CONNECT button on the THM4000 Wireless Adapter. After a short delay, the CONNECTED status light will glow
steady green..
Link optional accessories to wireless network
4
MCR32943
RedLINK Internet Gateway
Press and release the button on the bottom of the Internet
Gateway. After a short delay, the RedLINK status light will glow
steady green.
The Internet Gateway must be registered online before
use at www.mytotalconnectcomfort.com. Enter the MAC
ID and MAC CRC numbers located on the bottom of
the Internet Gateway. For additional information, see
instructions provided with the device.
MCR32942
CONNECT
WIRELESS SETUP
Portable Comfort Control
The linking procedure will time out if there is no keypress for 30 minutes. To begin again,
press and hold in the lower right corner of the screen until the display changes (about 3
seconds).
Press CONNECT on the Portable Comfort Control display screen. Press DONE when the
screen displays "Connected." Press NO at the next screen to save and exit. (Or press
YES to link another thermostat.)
Error messages:
E1 29 Incompatible device cannot be connected.
E1 34 Low RF signal. Move device to a different location and try
again.
E1 38 Make sure the thermostat is in Wireless Setup mode,
and the Portable Comfort Control is at least 2 feet away.
MCR33096
After a short delay, the status light will glow
green for 15 seconds. If the status light
turns red, the remote did not link with the
thermostat for the connection process.

CTK04 ComfortNet™ Communicating Thermostat
11 I/O-CHTSTAT03 69-2688—11
Mount optional accessories
1 Mount the sensor on a vertical exterior
wall, at least 6 inches below any
overhang. Choose a location protected
from direct sunlight.
2 Place sensor securely in bracket, facing
away from wall.
5
M28491
M28849A
[If no sensors are used, skip to Section 6.]
To install outdoor air sensor
To install indoor air sensor
To install Entry/Exit Remote or Vent Boost Remote
1 Remove the wallplate and mount it 4
to 6 feet above the floor on an interior
wall. Drill 3/16-inch holes for drywall,
7/32-inch for plaster.
2 Attach sensor securely to wallplate as
shown.
Mounting the remote is optional.
1 Remove the front cover from the
remote.
2 Use provided screws and wall anchors
to fasten the remote to the wall. Drill
3/16-inch holes for drywall, 7/32-inch
for plaster.
3 Replace the cover on the remote.
M32936B
M33095
Do not install the indoor air sensor where it can be affected by:
• Drafts or dead spots behind doors and in corners.
• Hot or cold air from ducts.
• Radiant heat from sun or appliances.
• Concealed pipes and chimneys.
• Unheated (uncooled) areas such as an outside wall

System Installation Guide
12
69-2688—11 I/O-CHTSTAT03
Installer options (ISU)
6
Create Setup: Press CREATE SETUP to set all system settings one
by one.
View/Edit Current Setup: Press VIEW/EDIT CURRENT SETUP to
select a specific function and make quick changes.
Installer Test: Press INSTALLER TEST to quickly determine if the
heat, cool, fan and thermostat are operating properly. Minimum off
timers are ignored during the test.
Data Logs: Press DATA LOGS to view the Alerts Log and User
Interactions Log.
Wireless Device Manager: Press WIRELESS DEVICE MANAGER
to add or remove wireless accessories.
Advanced Options: Press ADVANCED OPTIONS to setup the
thermostat using a USB device or to restore the thermostat to the
factory default settings. See page 2 for more information on the USB
port.
TIP:You can use the thermostat USB port to download all system configuration and installer options, including your company
name and contact information.You can upload this data to each thermostat you install, to save time.
To setup the thermostat, press MENU and scroll down to press INSTALLER OPTIONS.
Enter the date code (password) when prompted. The date code is printed on the
back of the thermostat; or press MENU > EQUIPMENT STATUS to find the date code.
After you enter the password, press CREATE SETUP to setup the thermostat.
A brief summary of installer options follows. You can download a complete list of all
options at http://customer.honeywell.com.
1000 Language B
1010 Residential/Commercial B
1030 Device Name B
1030 Device Name on Home Screen C
1040 Programmable/Non-programmable B
1050 Fahrenheit/Celsius B
1052 Indoor Equipment Type B
1053 Air Handler Heater Kit Installed B
1054 Outdoor Equipment Type B
1056 Air Conditioner Communication B
1058 Furnace Type B
1059 Air Conditioner/Heat Pump Type B
1060 Outdoor Air Sensor B
2190 System Zoning - Backup Heat Control B
3000 Manual/Auto Changeover B
3000 Auto Changeover Deadband B
3010 Temperature Control Options B
3020 Finish With High Cool Stage B
3021 Finish With High Heat Stage B
3030 Staging Control - Cool Differentials B
3050-3060 Staging Control - Heat Differentials B
3090 Staging Control - Backup Heat Differentials B
3110 Backup Heat Upstage Timer B
3120 Outdoor Compressor Lockout B
3120 Outdoor Backup Heat Lockout B
3140 Cool/Compressor Cycles Per Hour B
3150 Heat Cycles Per Hour B
3160 Backup Heat Cycles Per Hour B
3170-3190 Cooling Derivative, Integral, Throttling range C
3200-3220 Heating Derivative, Integral, Throttling range C
3240 Minimum Compressor Off Time B
3260 Extended Fan Run Time in Cool B
3260 Extended Fan Run Time in Heat B
4000 Number of Schedule Periods B
4010 Pre-occupancy Purge Duration C
4020 Override: Standard or Initiate Occupancy C
4030 Override Duration C
4050 Minimum Recovery Settings - Heat C
4060 Maximum Recovery Settings - Heat C
4070 Minimum Recovery Settings - Cool C
4080 Maximum Recovery Settings - Cool C
4090 Adaptive Intelligent Recovery R
4100 Minimum Cool Setpoint B
4100 Maximum Heat Setpoint B
4110 Keypad Lockout B
4120 Entry/Exit Remote -
Home/Occupied Cool Setpoint B
4120 Entry/Exit Remote -
Home/Occupied Heat Setpoint B
4130 Entry/Exit Remote -
Away/Unoccupied Cool Setpoint B
ISU Function ISU Function
R: Residential C: Commercial B: Both

CTK04 ComfortNet™ Communicating Thermostat
13 I/O-CHTSTAT03 69-2688—11
ComfortNet User Menu
Press MENU > COMFORTNET USER MENU
Press MENU and scroll down to press COMFORTNET USER MENU. Enter the date code
(password) when prompted. The date code is printed on the back of the thermostat;
or press MENU > EQUIPMENT STATUS to find the date code.
Each piece of equipment is divided into categories which may include: (Not all
menu options listed here may be available. Additional menu options may be dis-
played on the thermostat.)
• Diagnostics:Provides a fault history of the equipment and allows the
installer to clear the fault history.
• Identification: Provides the model and serial number of the equipment and
software revision information.
• Sensors: Provides the sensor data of the equipment. In some instances, it
4130 Entry/Exit Remote -
Away/Unoccupied Heat Setpoint B
4140 Entry/Exit Remote -
Vacation/Holiday Cool Setpoint B
4140 Entry/Exit Remote -
Vacation/Holiday Heat Setpoint B
5040 Indoor Sensors Used for Temperature Control B
7000 Filter Type B
7020 Number of Air Filters B
7110 Air Filter Replacement Reminder B
7110 Air Filter 2 Replacement Reminder B
7120 EAC Cell Cleaning Reminder B
7120 EAC Pre-Filter Cleaning Reminder B
7120 EAC Post-Filter Replacement Reminder B
8000 Humidifier Type B
8010 Indoor Sensor Used for Humidification Control B
8050 Humidification - Window Protection B
8060 System Modes Allowing Humidification B
8070 Humidification Control B
8100 Clean Tank / Water Filter Replacement Reminder B
8100 Humidifier Pad Replacement Reminder B
9000 Dehumidification Equipment B
9010 Indoor Sensor Used for Dehumidification Control B
9020 Humidity Sensor Displayed on the Home Screen B
9070 Dehumidification - Overcooling Limit R
9080 Dehumidification Control C
9090 Dehumidification Minimum On Time C
9100 High Humidity Comfort Reset Setting C
9180 Dehumidification Away Mode B
9190 Dehumidification Away Mode - Fan Control B
9200 Dehumidification Away Mode -
Low Limit Temperature B
9200 Dehumidification Away Mode -
Temperature Setting B
9200 Dehumidification Away Mode -
Dehumidification Setting B
9210 Dehumidifier Filter Replacement Reminder B
10000 Ventilation Type B
10050 Ventilation Control Method B
10090 Number of Bedrooms R
10090 Size of House R
10100 Enter Equipment Ventilation Rate R
10120 Ventilation Percent On Time B
10170 Ventilator Filter Cleaning Reminder B
11000 Number of UV Devices B
11050 UV Bulb Replacement Reminder B
11050 UV Bulb 2 Replacement Reminder B
12000 Installer Custom Reminders B
14000 Clock Format B
14010 Daylight Saving Time B
14020 Indoor Temperature Display Offset B
14020 Indoor Humidity Display Offset B
15000-15020 Dealer name, phone, email, website, message B
Installer options (ISU)
6
ISU Function ISU Function
may allow the installer to setup or turn off a sensor.
• Setup: Allows the installer to change the settings of the equipment.
• Status: Provides the current status of the equipment.
See equipment installer manual for specific submenu options available within
each category.

System Installation Guide
14
69-2688—11 I/O-CHTSTAT03
Wiring humidifier to the IFC
Wiring TrueEASE to IFC
Wiring TrueSTEAM to IFC
To change installer setup (ISU) information, see pages 12-13.
IFC
1
2
R
C
THERMOSTAT
1
2
R
C
HUM
HUM
1. WIRE THERMOSTAT AND TrueSTEAM AS SHOWN.
2. SET THERMOSTAT ISU 8000 TO “STEAM”.
3. SET TrueSTEAM DIP SWITCHES AS SHOWN (3 DOWN, 4 UP, 5 DOWN).
NOTE
FAN INTERLOCK IS HANDLED BY THE COMFORTNET COMMUNICATION.
TrueSTEAM DIP SWITCHES
TRUESTEAM
MCR33172
24 V
24 V
HUM
HUM
C
GT
R
RT
GF
EXT
6
5
43
2
ON
OFF
1
AFS MONITOR RECOMMENDED
IFC
1
2
R
C
THERMOSTAT
1
2
R
C
HUM
HUM
1. WIRE THERMOSTAT AND TrueEASE AS SHOWN.
2. SET THERMOSTAT ISU 8000 TO “BYPASS OR FAN POWERED”.
3. SET TrueEASE DIP SWITCHES AS SHOWN :
• TOP DIP SWITCH – SET TO THE RIGHT
• BOTTOM DIP SWITCH – SET TO THE LEFT
NOTE
FAN INTERLOCK IS HANDLED BY THE COMFORTNET COMMUNICATION.
MCR33173
TrueEASE DIP SWITCHES
BYPASS
HUM
CONTROL
FAN
POWERED
TrueEASE

CTK04 ComfortNet™ Communicating Thermostat
15 I/O-CHTSTAT03 69-2688—11
Heat pump with outdoor temperature lockouts
Outdoor temperature lockouts are optional. See Installer Setup
options (ISU 3120).
Heat pump only
Heat pump with backup heat as needed *
Backup heat only
Heat pump only
Heat pump or backup heat operates *
Backup heat only
Outdoor temperatureOutdoor temperature
Backup heat lockout
Backup heat lockout
Compressor lockout
Compressor lockout
* No backup heat unless indoor temperature drops to selected Backup Heat Differential setting, or Backup Heat
Upstage Timer expires. Heat pump stays ON when backup heat turns on.
* No backup heat unless indoor temperature drops to selected Backup Heat Differential setting, or Backup
Heat Upstage Timer expires. Heat pump turns OFF when backup heat turns on.
Electric - Backup heat allowed to run with heat pump
Fossil Fuel - Backup heat NOT allowed to run with heat pump

System Installation Guide
16
69-2688—11 I/O-CHTSTAT03
Backup heat differential and upstage timer
Basic and Advanced Temperature Control Options (ISU 3010)
A backup heat differential and backup heat upstage timer can be set on heat pump
systems with backup heat. See installer setup options (ISU 3090-3110).
Normal operation
When the Backup Heat Differential is set to Comfort, the thermostat uses backup
heat as needed to keep the indoor temperature within 1° F (0.5° C) of the setpoint.
When the Backup Heat Differential is set to 2° F or higher, backup heat is not used
unless the indoor temperature drops to the Backup Heat Differential setting or the
Backup Heat Upstage Timer expires, whichever occurs first. The upstage timer starts
when the highest stage of the previous equipment type turns on.
Manual temperature change
When the Backup Heat Differential is set to Comfort, the thermostat uses backup
heat as needed to keep the indoor temperature within 1° F (0.5° C) of the setpoint.
When the Backup Heat Differential is set to 2° F or higher, if the heat pump is mak-
ing progress as expected, backup heat will not be used to reach the new setpoint.
Set to a higher number to use less backup heat (a greater difference between the
current indoor temperature and the new setpoint is required to turn on backup heat).
See notes below.
Programmed recovery
If the heat pump is making progress as expected, backup heat will not be used to
reach the setpoint of the next program period. Backup heat is always restricted dur-
ing a programmed recovery when the Adaptive Intelligent Recovery feature is used.
See note below.
Basic Options: The Installer Setup displays basic temperature control options
which include Backup Heat Differential, Backup Heat Upstage Timer and Outdoor
Temperature Lockouts. Note: Outdoor Temperature Lockouts only apply to Heat
Pump applications.
Advanced Options: The Installer Setup displays both Basic and Advanced Options.
Advanced temperature control options include Finish With High Cool Stage, Finish
With High Heat Stage, Temperature Differential settings between all stages and
Cycle Rate settings per stage.
During a programmed recovery (or when the temperature setpoint is changed by the user), the thermostat waits to turn on the
backup heat depending on system performance, load conditions and how many degrees the temperature setpoint is changed.
Backup heat will be used ONLY when the temperature is not rising quickly enough to reach the setpoint in a reasonable time.
If the backup heat was used in the last 2 hours because the heat pump was not able to maintain the setpoint, the thermostat
may turn on the backup heat earlier when the user raises the setpoint.
Finish With High Heat or Cool Stage - When a multi-stage heating or cooling system is used, this feature keeps the high stage
of the heating or cooling equipment running until the desired setpoint is reached.

CTK04 ComfortNet™ Communicating Thermostat
17 I/O-CHTSTAT03 69-2688—11
Humidification
The thermostat reads the indoor humidity level and allows the user to set a humidifi-
cation setting with or without window protection.
Window Protection
Window Protection limits the amount of humidity to prevent frost or condensation on
windows. Window Protection (ISU 8050) requires an outdoor sensor.
The maximum humidity level that is allowed ("Window Limit") is displayed on the
Humidification Settings screen. The thermostat prevents frost or condensation on
windows by not allowing the humidity to go above the Window Limit when it is con-
trolling the humidifier. This helps inform the user as to why their humidity setting
might not be reached at times. The Window
Limit is based on the current outdoor tempera-
ture and the user's window protection setting.
If Window Protection is turned Off, the ther-
mostat controls the humidity level to the user's
desired humidity setting. Frost or condensation
may appear on windows.
Dehumidification - Residential
The thermostat reads the indoor humidity level and allows the user to set a dehu-
midification setting.
When set up for dehumidification using the cooling system, an overcooling limit can
be set from 0 F to 3 F (ISU 9070). The thermostat uses the cooling system to reduce
humidity by lowering the temperature up to 3 F below the current cool setpoint until
the desired humidity level is reached.
To see all dehumidification options, press MENU > INSTALLER OPTIONS > VIEW/EDIT CURRENT SETUP >
DEHUMIDIFICATION.
To see all humidification options, press MENU > INSTALLER OPTIONS > VIEW/EDIT CURRENT SETUP >
HUMIDIFICATION.

System Installation Guide
18
69-2688—11 I/O-CHTSTAT03
Dehumidification - Commercial
The thermostat reads the indoor humidity level and allows the user to set a
dehumidification setting.
Dehumidification using the cooling system has the following methods of
dehumidification control (ISU 9080):
Basic: This option uses the cooling system to reach the desired humidity level.
Minimum On Time and High Humidity Comfort Reset are not used with this method.
This option should only be used if the equipment can lower the fan speed in a call for
dehumidification.
Minimum on Time (ISU 9090): This option ensures that the compressor runs long
enough to effectively reduce humidity when the cooling equipment is cycled on. The
compressor will run for the minimum "on time" you set until the desired humidity level
is reached.
High Humidity Comfort Reset (ISU 9100): This option uses the cooling system
to lower the temperature up to 5 F below the current cool setpoint until the desired
humidity is reached. The high humidity comfort range is from 1 to 5 F.
High Humidity Comfort Reset with Minimum On Time (ISU 9090 and ISU
9100): This method uses both options above to reduce humidity while maintaining a
comfortable temperature.
To see all dehumidification options, press MENU > INSTALLER OPTIONS > VIEW/EDIT CURRENT SETUP >
DEHUMIDIFICATION.

CTK04 ComfortNet™ Communicating Thermostat
19 I/O-CHTSTAT03 69-2688—11
Dehumidification Away Mode
Dehumidification Away Mode protects the home when unoccupied for long periods
of time during hot and humid weather by maintaining the desired humidity and
temperature settings.
To start Dehumidification Away Mode, press
Menu, then press Dehumidification Away Mode.
The thermostat automatically follows settings
that are set by the dealer during installer setup.
Press Cancel to end Dehumidification Away
Mode.
Southern Dehumidification Away Mode
Options: (ISU 9180 to 9200)
• Fan: Auto, On or Circulate
• Low Limit Temperature Setting: The
thermostat allows the cooling system
to lower the indoor air to the Low Limit
Temperature Setting to control humidity.
• Temperature Setting: The temperature
maintained while Dehumidification Away
Mode is active and the desired humidity level is satisfied.
• Dehumidification Setting: The desired humidity level while Dehumidification
Away Mode is active.
Ventilation
Ventilation Control Method (ISU 10050)
The thermostat can control the fan to meet either ASHRAE or Percent On Time
settings. If the required ventilation has not been achieved for ASHRAE or Percent On
Time during calls for heat and cool, the thermostat will force the fan on.
• ASHRAE: The thermostat operates the fan to meet the ASHRAE 62.2
ventilation standard based on CFM, number of bedrooms, and square footage
of the house. ASHRAE 62.2 can only be met if the fan is running. If the fan is
off for any reason (set up to turn Off during Sleep period, turned off by user
etc.), ASHRAE 62.2 is not met during those times.
• Percent On Time: The thermostat operates the fan based on a percentage
entered in the installer setup (ISU 10120). For example, if Percent On Time
is set to 50%, the fan will run at random times during a 1 hour period until it
reaches a 50% run time (approximately 30 minutes). Options 10% to 100%.
To see all ventilation options, press MENU > INSTALLER OPTIONS > VIEW/EDIT CURRENT SETUP >
VENTILATION.

System Installation Guide
20
69-2688—11 I/O-CHTSTAT03
Indoor sensor operation
Temperature control
The thermostat can be set to respond to its
internal temperature sensor, or to an optional
remote indoor sensor. If multiple sensors are
used, the thermostat will respond to an aver-
age of temperatures detected at each sensor.
Humidification control
If optional remote indoor sensors are installed,
you can choose which sensor you want to use
for humidification control. You can use a differ-
ent sensor for dehumidification.
Dehumidification control
If optional remote indoor sensors are installed,
you can choose which sensor you want to use
for dehumidification control. For example, you
can use one sensor for humidification control,
and another for dehumidification.