Trane TCONT900AC43UA Assembly instructions

INSTALLER’S GUIDE
69-2079-05
Pub No. 18-HD32D1-2
TCONT900AC43UA
COMFORT CONTROL -
4 HEAT (GAS, OIL*, OR ELECTRIC)/3 COOL/HEAT PUMP
COMMUNICATING PROGRAMMABLE
3 WIRE HOOKUP
ALL phases of this installation must comply with NATIONAL, STATE, AND LOCAL CODES
NOTE: If this control is replacing a control that contains mercury in a sealed tube, do not place your old control in the
trash. Dispose of properly.
NOTE: Contact your local waste management authority for instructions regarding recycling and the proper disposal of
an old control.
INTRODUCTION
The TCONT900AC43UA is a communicating programmable Comfort Control that supports single-stage or multi-stage
heat/cool and heat pump applications. It is a wall mounted, low voltage (24VAC) communicating Comfort Control with
backlit LCD and a touch screen display. Room temperature is maintained by controlling the operation of heating,
cooling, heat pump, and dual fuel systems via digital, 2-way communications. The Comfort Control will communicate
with and identify all ComfortLinkTM II components in the system. It is easily manually configured via the user friendly
Installer Setup menu. The Comfort Control features include separate heating and cooling setpoints, selectable auto or
manual changeover, menu driven 7-day programming, adjustable filter reminders, and outdoor temperature sensing.
Setup selections and diagnostics are stored indefinitely in the Comfort Control’s nonvolatile memory eliminating the
need for battery backup.
* See System and Fan Keys section for specific information.
Accessories
Optional
BAYSEN01ATEMPA - Outdoor Sensor - For use with communicating outdoor equipment
BAYTAM00AC00UA - Telephone Access Module (TAM)
Table 1. TCONT900AC43UA Comfort Control
Power Method Changeover
System Selection
and Fan Keys* Fan Selection Comments
24 Vac common wire Automatic or Manual
selectable
Heat-Off-Cool-Auto
Emergency Heat
On-Auto-Circ System and Fan
selection vary, based on
system type
Humidity sensor to
control dehumidification
and humidification

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 2
PRODUCT SPECIFICATIONS
This comfort control contains a Lithium battery which may contain Perchlorate material. Due to State Law in California,
the following statement is required:
Perchlorate Material - special handling may apply. See www.dtsc.ca.gov/hazardouswaste/perchlorate
Power Source: 18-30 VAC, Class II, 50/60Hz
Storage Range: -30°F-150°F (-34.4°C-65.6°C), 5%-90% RH non-condensing
Operating Temperature Range: 0°F-120°F (-17.8°C-37.2°C), 5%-90% RH non-condensing
System Mode: Heat, Cool, Auto, Emergency Heat, and Off
Fan Mode: On, Auto, and Circ
Cooling Setpoint Temperature Range: 60°F-99°F (15.5°C-37.0°C), 1°F (0.5°C) resolution
Heating Setpoint Temperature Range: 50°F-90°F (10°C-32.0°C), 1°F (0.5°C) resolution
Indoor Temperature Display Range: 40°F-99°F (4.5°C-37.0°C)
Outdoor Temperature Display Range: -40°F-127°F (-40°C-53.0°C)
Indoor Humidity Display Range: 0%-99%, 1% resolution
Minimum Cycle Off Time Delay: Compressor: 5 minutes
Heat: 0 minutes

TCONT900AC43UA
Pub. No. 18-HD32D1-2
3 69-2079—05
INSTALLATION
When Installing this Product...
1. Read these instructions carefully. Failure to follow
these instructions can damage the product or cause
a hazardous condition.
2. Check the ratings given in the instructions and on
the product to make sure the product is suitable for
your application.
3. Installer must be a trained, experienced service
technician.
4. After completing installation, use these instructions
to check out the product operation.
WARNING
Voltage Hazard. Can cause electrical shock or
equipment damage.
Disconnect power before beginning installation.
Location
Install the Comfort Control about 5 ft. (1.5m) above the
floor in an area with good circulation at average
temperature. See Figure 1.
Fig. 1. Selecting Comfort Control Location
Do not install the Comfort Control 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
behind the Comfort Control.
Sub-base Installation
The Comfort Control can be mounted horizontally on the
wall or on a 2 in. by 4 in. wiring box. Position sub-base
horizontally on the wall or on a 2 in. by 4 in. wiring box.
1. Turn OFF all power to heating and coolingequip-
ment.
2. If an existing Comfort Control is being replaced:
a. Remove existing Comfort Control from wall.
b. Disconnect wires from existing control, one at a
time. Be careful not to allow wires to fall back
into wall.
c. As each wire is disconnected, record wire color
and terminal marking.
d. Discard or recycle old Comfort Control.
3. Separate the Comfort Control from the subbase to
expose mounting holes.
4. Position and level the sub-base wallplate (for
appearance only). The Comfort Control functions
properly even when not level.
5. Use a pencil to mark the mounting holes.
6. Remove the sub-base from the wall and drill two
3/16 in. holes in the wall (if drywall) as marked. For
firmer material such as plaster, drill two 7/32 in.
holes. Gently tap anchors (provided) into the drilled
holes until flush with the wall.
7. Position the sub-base over the holes, pulling the
wires through the wiring opening.
8. Insert the mounting screws in the holes and tighten.
Wiring
All wiring must comply with local electrical codes and
ordinances. See Figures 2 and 3 wiring diagrams for
specific equipment applications. Refer to Table 2 for
terminal designations.
WARNING
Voltage Hazard. Can cause electrical shock or
equipment damage.
Disconnect power before beginning installation
NOTE: The maximum total cable length for the entire
Comfort Control communicating system is 500
feet 18 AWG. The maximum distance of any
single cable from a transformer is 250 feet
18 AWG.
1. Loosen the terminal screws on the sub-base. Insert
wires into the terminal block next to the loosened
screw. See Figure 4.
IMPORTANT
Use 18-gauge color-coded Comfort Control cable for
proper wiring. Shielded cable is not
typically required. Keep this wiring at least one foot away
from large inductive loads such as
Electronic Air Cleaners, motors, line starters, lighting
ballasts and large distribution panels. Failure to follow
these wiring practices may
introduce electrical interference (noise) which can cause
erratic system operation. All unused Comfort Control wire
to be grounded at indoor unit chassis ground only.
Shielded cable may be required if the above wiring
guidelines cannot be met. Ground the shield only to the
system chassis.
5 FEET
[1.5 METERS]
YES NO
NO
NO

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 4
Fig. 2. Field Wiring Diagram, Communicating Indoor Unit - Communicating Outdoor Unit
Fig. 3. Field Wiring Diagram, Communicating Indoor Unit - Single Stage Cooling Unit
B
BK
Y2
Y1
O
R
D
W1
W3
G
W2
B
D
B
R
D
X2
Y2
Y1
O
CLII
COMFORT
CONTROL
24VAC HOT
24VAC
Common
DATA
CLII
INDOOR
UNIT
CLII
LOW VOLTAGE WIRING TO BE NO. 18
AWG MINIMUM CONDUCTOR.
OUTDOOR
UNIT
B
BK
Y2
Y1
O
R
D
W1
W3
G
W2
B
B
R
D
Y
CLII
COMFORT
CONTROL
24VAC HOT
24VAC
Common
DATA
CLII
INDOOR
UNIT
SINGLE
STAGE AIR
CONDITIONER
LOW VOLTAGE WIRING TO BE NO. 18
AWG MINIMUM CONDUCTOR.

TCONT900AC43UA
Pub. No. 18-HD32D1-2
5 69-2079—05
2. Securely tighten each terminal screw.
3. Push excess wire back in the hole.
4. Plug the hole in the wall with nonflammable insula-
tion to help prevent drafts from adversely affecting
Comfort Control operation.
Mounting Comfort Control on Sub-base
NOTE: To remove the Comfort Control from the wall,
pull straight out.
1. Align the terminal screw block with the pins on the
back of the Comfort Control.
2. Push the Comfort Control straight onto the wall-
plate. See Figure 4.
3. Perform installation of all other system equipment.
Fig. 4. Comfort Control
4. Turn ON power to the heating and cooling
equipment.
INITIAL POWER-UP
Power-Up Sequence
The ComfortLinkTM II communicating Comfort Control will
communicate and identify all ComfortLinkTM II
components in the system.
Discovery Mode
Discovery mode begins when ComfortLinkTM II
communicating Comfort Control is first installed and
power is connected. For communicating equipment, the
Comfort Control automatically configures the equipment
type, number of stages, cycle rates for each stage, and
compressor stage ratios based on the information it
received during Discovery mode.
NOTE: While in Discovery mode, the LED indicator
located in the upper right corner of the Comfort
Control will be illuminated.
NOTE: All discovered values will be saved into memory.
If a communicating device goes missing (Err 89)
or changes in value (Err 126) the error will be
broadcast to the comfort control screen. (Restor-
ing communications will clear this error or see
ISU 0706 to reset the system configuration).
NOTE: The communicating Comfort Control can be
reset (ISU 0710) to factory default settings.
NOTE: If no equipment is connected during the Auto-
Discovery process, the system mode will be
stuck at “OFF” and no equipment will run.
NOTE: To change the default/discovery settings, enter
the Installer Setup menu (see Table 4) and select
the desired item.
NOTE: Only ISU settings with an “E” will be Auto-
Discovered. Manually changing an ISU setting to
an option other than “E” disables Discovery
mode for that ISU setting.
NOTE: See Table 3 for default cycle rate settings.
Table 2. Terminal Designations
Terminal
Designations Function
D Data
R Power - 24 Vac (hot)
B Power - 24 Vac (Common)
WALL
Table 3. Typical Cycle Rate Settings
System
Cycles Per
Hour
Steam, Gravity 1
Hydronic Heat, Condensing Gas
Furnaces, Compressor Stages
3
Gas or Oil Forced Air, Auxiliary Heat 5
Electric Heat, Emergency Heat 9

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 6
1. Communicating Indoor Unit -
Communicating Outdoor Unit
For a fully communicating system, the communicating
Comfort Control will automatically configure the indoor
and outdoor equipment configuration and cycle rates for
each stage. See Figure 2.
2. Communicating Indoor Unit - Single
Stage Cooling Unit
For a partially communicating system, the communicating
Comfort Control will automatically configure the indoor
equipment configuration and cycle rates for each stage.
See Figure 3.
NOTE: The outdoor equipment configuration will default
to a single stage cooling unit.
ADJUSTING REAL TIME CLOCK
Setting Calendar and Time
Locate and remove the tab labeled “Remove” in the lower
left corner on the Comfort Control back. The tab must be
removed to activate the real-time clock. See Figure 5.
Fig. 5. Clock Activation
NOTE: If the system is not powered, the Real Time
Clock battery life is approximately 20 weeks.
The Comfort Control is designed to automatically keep
the current time and day in memory for up to ten years
under normal use once calendar is set. When the Comfort
Control is powered, the display is ready for the calendar
date to be entered. See Figure 6.
1. Use the arrow keys to set the Year, Month and Day,
as shown in Figure 6.
2. Press the Done key.
3. Use the arrow keys to set the current time. See Fig-
ure 6.
4. Press the Done key.
Fig. 6. Control Time and Date Settings
REMOVE DURING
INSTALLATION
REMOVE DURING
INSTALLATION
REMOVE TAB TO ACTIVATE REAL TIME CLOCK
DONE
MON
MON
TUE WED
WED
THU
THU
FRI
FRI
SA
SA
T
T
SUN
CHANGE FILTER UV LAMP HUMIDIFIER PAD
OK TO PICK MULTIPLE DAYS SCREEN LOCKED
DONE
MON
MON
WED
WED
THU
THU
FRI
FRI
SA
SA
T
T
SUN
PM
CHANGE FILTER UV LAMP HUMIDIFIER PAD
OK TO PICK MULTIPLE DAYS SCREEN LOCKED
SET CURRENT DAY
SET MONTH
USE ARROWS TO SET YEAR AND TIME
M22645

TCONT900AC43UA
Pub. No. 18-HD32D1-2
7 69-2079—05
INSTALLER SETUP (ISU)
The Comfort Control works with many different system
types. The installer can use the Installer Setup menu to
change factory settings to customize installations. See
Table 4.
Entering Installer Setup
Follow these steps to enter the Installer Setup:
1. Be sure the Comfort Control is powered.
NOTE: If necessary, press the Done key to return to the
home screen.
2. Press and release the system key.
3. Press and hold the two blank keys on either side of
the center key for approximately five seconds until
screen changes. See Figure 7.
4. Release the two blank keys when the screen on the
Comfort Control matches the screen in Figure 8.
5. See Figure 8 to review how the Comfort Control
keys are used during Installer Setup. See Table 4
for the Installer Setup Numbers and Settings.
6. Press the Done key to exit the Installer Setup-
screen.
NOTE: Manually changing an ISU setting to an option
other than “E” disables Discovery mode for that
ISU setting. If power is lost, all custom settings
are retained in the memory.
Fig. 7. Entering Installer Setup
Fig. 8. Installer Setup Start Screen
D
O
N
E
CANCEL
MON
T
UE
WED
THU
FRI
SA
T
A
A
T
SUN
PM
S
Y
S
TE
M
EM HEAT
O
F
F
COOL
Followin
g
Sc
h
edu
l
e
In
s
i
de
Se
t T
o
DONE
O
MON
WED
THU
FRI
SA
T
A
A
T
SUN
INSTALLER
SETUP NUMBER FACTORY
SETTING
ADVANCE TO NEXT
INSTALLER SETUP
PRESS TO EXIT
INSTALLER SETUP
CHANGE THE
FACTORY
SETTING
A
U
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description
Date (Year Upper) 0120 20 20, 21 Select the first two digits of
current calendar year (20
for 2007)
2001-2178 available.
Date (Year Lower) 0130 06 00-99 Select the last two digits of
current calendar year (07
for the year 2007)
2001-2178 available.
Date (Month) 0140 1-12 Select number that
represents current
calendar month
Date (Day) 0150 1-31 Select number that
represents current
calendar date

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 8
Schedule Options 0160 4 0, 4 0 - Non-programmable
4 - 7 Day programmable
When ISU0160 is changed
from 0 (non-programmable
to 4 (programmable),
“Permanent Hold” will
display under the time icon.
This goes away when the
schedule key is hit or when
the schedule menu is
entered.
Restore Energy Star
Schedule
0165 0 0, 1 0 - No
1 - Resets the schedule to
default Energy Star
No ISU or USU settings
affected.
System Selection 0172 E E, 1-3 E - Auto-Discover
1 - Heat/Cool
2 - Heat Pump
3 - Heat Only (no fan)
If no equipment is
connected during the Auto-
Discovery process, the
system mode will be stuck
at “off” and no equipment
will run.
Compressor Stages 0174 E E, 0-2 E - Auto-Discover
0 - None
1 - Single Stage
2 - Two Stage/Two Step
A minimum of 1H or 1C is
required.
Heater Stages 0176 E E, 0-3 E - Auto-Discover
0 - None
1 - Single Stage
2 - Two Stage
3 - Three stage
A minimum of 1H or 1C is
required.
Fan Operation 0180 E E, 0, 1 E - Auto-Discover
0 - Equipment controls fan
operation in heat mode
(fossil).
1 - Comfort Control
controls fan operation in
heat mode (electric).
Only seen if ISU 0172 is set
to 1.
Indoor Unit Type 0181 E E, 0, 1 E - Auto-Discover
0 - Non-variable Speed
1 - Variable Speed
Compressor Low
Stage Airflow
0182 E
2 Stage =
50%
2 Step =
80%
E, 25, 30,
35, 40,
45,
50, 55,
60,
65, 70,
75,
80
E - Auto-Discover,
25% - 80% in 5%
increments
Only shown for variable
speed indoor units.
Options may vary based on
actual system installed.
Compressor Stage 2
Airflow
0183 100% 100 Not Auto-discovered Only shown for variable
speed indoor units.
Options may vary based on
actual system installed.
Heat Pump Warm Air
Discharge
0185 0 0, 1 0 - Disabled = 100%
1 - Enabled = 80%
Only shown for variable
speed indoor units.
Continuous Fan
Airflow
0186 50 25, 30,
35,
40, 45,
50,
55, 60,
65,
70, 75,
80,
85, 90,
95,
100
25% - 100% in 5%
increments
Only shown for variable
speed indoor units.
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
Pub. No. 18-HD32D1-2
9 69-2079—05
Backup Heat source
(Aux heat)
0200 E E, 0, 1 E - Auto-Discover
0 - Electric
1 - Fossil
HP only
1st Stage
Compressor Cycles
Per Hour (CPH)
0220 E E, 2-6 E - Auto-Discover
2 - 6 is available;
(3 is recommended)
Default value is 3 CPH if
nothing is discovered.
2nd Stage
Compressor Cycles
Per Hour (CPH)
0230 E E, 2-6 E - Auto-Discover
2 - 6 is available;
(3 is recommended)
Default value is 3 CPH if
nothing is discovered.
1st Stage Heater
Cycles Per Hour
(CPH)
0240 E E, 2-6 E - Auto-Discover
2 - 6 is available;
(3 is recommended)
Default value is 3 CPH if
nothing is discovered.
2nd Stage Heater
Cycles Per Hour
(CPH)
0250 E E, 2-6 E - Auto-Discover
2 - 6 is available;
(5 is recommended)
Default value is 5 CPH if
nothing is discovered.
3rd Stage Heater
Cycles Per Hour
(CPH)
0260 E E, 2-6 E - Auto-Discover
2 - 6 is available;
(5 is recommended)
Default value is 5 CPH if
nothing is discovered.
Continuous Backlit 0280 0 0, 1 0 - Backlit not on
continuously. Comfort
Control backlight comes on
with a key press.
1 - Backlit is on
continuously. Comfort
Control backlight will come
on full brightness
with a key press and
display will dim 45
seconds after the last
keypress.
Changeover 0300 1 0, 1 0 - Manual Changeover
1 - Auto Changeover
Deadband 0310 3 3-9 3 - 3°F (2.0°C)
4 - 4°F (2.5°C)
5 - 5°F (3.0°C)
6 - 6°F (3.5°C)
7 - 7°F (4.0°C)
8 - 8°F (4.5°C)
9 - 9°F (5.0°C)
Shown only if automatic
changeover is selected. If
ISU 0380 is set to
Integrated Temperature and
Humidity Control (ITHC),
the deadband is restricted
to a range of 5 to 9.
Temperature
Indication Scale
0320 0 0, 1 0 - Temperature is
displayed in °F
1 - Temperature is
displayed in °C
Daylight Savings 0330 2 0, 1, 2, 3 0 - Daylight savings is
disabled.
1 - Daylight savings is
enabled (US 1987)
2 - Daylight savings is
enabled (US 2007)
3 - Daylight savings is
enabled (Europe)
Set to 0 for areas that do
not follow daylight savings.
Outdoor Temperature
Sensor
0342 E E, 0, 1 E - Auto-Discover
0 - None
1 - Installed Sensor
All communicating outdoor
units are equipped with an
ambient temperature
sensor that will be auto-
discovered
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 10
Dual Fuel Heat Pump
Control
0345 1 0, 1, 2 0 - Compressor lockout
only
1 - Heat Pump Compressor
lockout and failed to
maintain heat protection
2 - Heat Pump Compressor
lockout and Auxiliary Heat
lockout and Failed to
maintain heat protection in
between. To access aux
heat lockout, select option
2.
If compressor is “Failing to
maintain heat”, revert to aux
heater above balance point.
Dual Fuel Heat Pump
Upstage to Furnace
Timer
0346 60 0, 30, 45,
60, 75
0 - Disabled
30 - 30 minutes
45 - 45 minutes
60 - 60 minutes
75 - 75 minutes
System will switch to gas
furnace to satisfy call for
heat if second stage
compressor timer expires.
Heat Pump
Compressor Lockout
Outdoor Temperature
0350 0,
40 (dual
fuel)
0, 5 - 60 0 - No compressor lockout
5 - 5°F (-15.0°C)
10 - 10°F (-12.0°C)
15 - 15°F (-9.5°C)
20 - 20°F (-6.5°C)
25 - 25°F (-4.0°C)
30 - 30°F (-1.0°C)
35 - 35°F (1.5°C)
40 - 40°F (4.5°C)
45 - 45°F (7.0°C)
50 - 50°F (10.0°C)
55 - 55°F (13.0°C)
60 - 60°F (15.5°C)
System will switch to gas
furnace to satisfy call for
heat if the highest
compressor stage,
continuous-run timer
expires.
Auxiliary Heat
Lockout Outdoor
Temperature
0360 0 0, 5 - 65 0 - No auxiliary heat
lockout
5 - 5°F (-15.0°C)
10 - 10°F (-12.0°C)
15 - 15°F (-9.5°C)
20 - 20°F (-6.5°C)
25 - 25°F (-4.0°C)
30 - 30°F (-1.0°C)
35 - 35°F (1.5°C)
40 - 40°F (4.5°C)
45 - 45°F (7.0°C)
50 - 50°F (10.0°C)
55 - 55°F (13.0°C)
60 - 60°F (15.5°C)
65 - 65°F (18.5°C)
Not available for dual fuel
unless option 2 is selected
in ISU#0345. Default will be
50 in this case.
1st Stage Heater
Defrost Balance
Point
0361 0 0, 5 - 55 0 - Disabled
5 - 5°F (-15.0°C)
10 - 10°F (-12.0°C)
15 - 15°F (-9.5°C)
20 - 20°F (-6.5°C)
25 - 25°F (-4.0°C)
30 - 30°F (-1.0°C)
35 - 35°F (1.5°C)
40 - 40°F (4.5°C)
45 - 45°F (7.0°C)
50 - 50°F (10.0°C)
55 - 55°F (13.0°C)
Only shown if outdoor
temperature is available.
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
Pub. No. 18-HD32D1-2
11 69-2079—05
2nd Stage Heater
Defrost Balance
Point
0362 40 0, 5 - 55 0 - Disabled
5 - 5°F (-15.0°C)
10 - 10°F (-12.0°C)
15 - 15°F (-9.5°C)
20 - 20°F (-6.5°C)
25 - 25°F (-4.0°C)
30 - 30°F (-1.0°C)
35 - 35°F (1.5°C)
40 - 40°F (4.5°C)
45 - 45°F (7.0°C)
50 - 50°F (10.0°C)
55 - 55°F (13.0°C)
Only shown if outdoor
temperature is available.
3rd Stage Heater
Defrost Balance
Point
0363 25 0, 5 - 55 0 - Disabled
5 - 5°F (-15.0°C)
10 - 10°F (-12.0°C)
15 - 15°F (-9.5°C)
20 - 20°F (-6.5°C)
25 - 25°F (-4.0°C)
30 - 30°F (-1.0°C)
35 - 35°F (1.5°C)
40 - 40°F (4.5°C)
45 - 45°F (7.0°C)
50 - 50°F (10.0°C)
55 - 55°F (13.0°C)
Only shown if outdoor
temperature is available.
Defrost Heater
Selection
0364 0 - 7 0 - None
1 - Aux1
2 - Aux2
3 - Aux3
4 - Aux1 and Aux2
5 - Aux2 and Aux3
6 - Aux1 and Aux3
7 - Aux1 and Aux2 and
Aux3
Default will be preset to the
maximum number of aux
heat stages available.
Only shown if Heater
Defrost Balance Point(s)
are disabled by selecting
“0” in ISU 0361, 0362 and/
or 0363.
Discharge
Temperature Sensor
0365 E E, 0, 1 E - Auto-Discover
0 - None
1 - Remote Sensor
Installed
For future use.
Leave at factory
default setting “E”
Indoor Humidity
Sensor
0370 1 0, 1, 2 0 - Disabled
1 - Internal sensor
2 - Remote sensor
Indoor Humidification
Control
0372 E, 0 E, 0, 1, 2 E - Auto-Discover
0 - Off
1 - Relative Humidity
Setpoint
2 - Dewpoint Control
Auto-Discover will discover
“0”
Dewpoint Control with Frost
Protection requires outdoor
temperature sensor
Humidifier Fan Action 0374 2 1, 2 1 - Fan turns on with
Humidifier
2 - Humidify only when
Heat is on
Only visible when ISU 0372
enabled. Fan will run for 2
minutes after humidifier
turns off.
Indoor
Dehumidification
Control
0380 1 0, 1, 4 0 - Off
1 - Integrated Temperature
and Humidity Control -
ITHC (RH Setpoint)
4 - Trane Droop (RH
Setpoint)
Deadband limited when in
Auto- Changeover Mode
and ITHC is enabled.
See “Dehumidification” on
page 19.
Comfort-RTM Delay 0381 0 0, 1, 2 0 - No Delay
1 - Comfort-RTM 15 sec
2 - Comfort-RTM 30 sec
Only shown for non-variable
speed indoor units
Dehumidification
Maximum Droop
0383 1 1, 2, 3 1 - 1°F (0.5°C)
2 - 2.0°F (1.0°C)
3 - 3°F (1.5°C)
Only shown if ITHC is
selected
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
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Dehumidification
Airflow
0387 100 80 - 100 80 - 80% Airflow
85 - 85% Airflow
90 - 90% Airflow
95 - 95% Airflow
100 - 100% Airflow
Only shown for variable
speed indoor units. See
Advanced Features section
for more information
Trane Proprietary
Humidity Control
0388 1 0, 1 0 - Disabled
1 - Enabled
Not shown if ISU0380 is set
to 0.
See Advanced Features
section for more information
Furnace Filter 1
Change Reminder
0500 E, 0 E, 0 - 14 E - Auto-Discover
0 - Disabled (reminder off)
1 - 10 run time days
2 - 30 run time days
3 - 60 run time days
4 - 90 run time days
5 - 120 run time days
6 - 180 run time days
7 - 270 run time days
8 - 365 run time days
9 - 30 continuous days
10 - 60 continuous days
11 - 90 continuous days
12 - 120 continuous days
13 - 180 continuous days
14 - 365 continuous days
When set to Auto-Discover
(and the discovered value is
not 0=disabled), the
Comfort Control will display
the filter timer value it
receives from the
ComfortLinkTM II
communicating filtering
device on the More screen.
To reset the filter timer of
the ComfortLinkTM II
communicating filtering
device, simply press the
More key to access the filter
timer value and then press
the Reset key. If no
ComfortLinkTM II
communicating filtering
device has been
discovered, the auto-
discovered value will default
to 0.
When not set to Auto-
Discover (and not set to
0=disabled), the Comfort
Control will display its
internal filter timer on the
More screen.
To reset the Comfort
Control's internal timer,
simply press the More key
to access the filter timer
value and then press the
Reset key.
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
Pub. No. 18-HD32D1-2
13 69-2079—05
Furnace Filter 2
Change Reminder
0501 E, 0 E, 0 - 14 E - Auto-Discover
0 - Disabled (reminder off)
1 - 10 run time days
2 - 30 run time days
3 - 60 run time days
4 - 90 run time days
5 - 120 run time days
6 - 180 run time days
7 - 270 run time days
8 - 365 run time days
9 - 30 continuous days
10 - 60 continuous days
11 - 90 continuous days
12 - 120 continuous days
13 - 180 continuous days
14 - 365 continuous days
When set to Auto-Discover
(and the discovered value is
not 0=disabled), the
Comfort Control will display
the filter timer value it
receives from the
ComfortLinkTM II
communicating filtering
device on the More screen.
To reset the filter timer of
the ComfortLinkTM II
communicating filtering
device, simply press the
More key to access the filter
timer value and then press
the Reset key. If no
ComfortLinkTM II
communicating filtering
device has been
discovered, the auto-
discovered value will default
to 0.
When not set to Auto-
Discover (and not set to
0=disabled), the Comfort
Control will display its
internal filter timer on the
More screen.
To reset the Comfort
Control's internal timer,
simply press the More key
to access the filter timer
value and then press the
Reset key.
Humidifier Pad
Replacement
Reminder
0510 E, 0 E, 0 - 3 E - Auto-Discover
0 - Disabled
1 - 90 continuous days
(30 run time days)
2 - 180 continuous days
(60 run time days)
3 - 365 continuous days
(90 run time days)
When controlling humidifier
settings, use run time days.
Otherwise, use calendar
days.
Adaptive Intelligent
Recovery
0530 1 0, 1 0 - Conventional recovery
is activated
1 - Adaptive Intelligent
Recovery control is
activated
Adaptive Recovery starts
recovery early to reach
setpoint by start of program
period.
Number of Periods 0540 4 2, 4 2 - Two Periods available
(Wake, Sleep)
4 - Four Periods available
(Wake, Leave, Return,
Sleep)
Selection applies to all days
of the week.
Not shown if
nonprogrammable is
selected.
Heat Temperature
Range Stop
0600 90 50 - 90 Highest heating setpoint.
Temperature range (1°F
increments) of heating
setpoint.
Shown in 1/2°C
Cool Temperature
Range Stop
0610 60 60 - 99 Lowest cooling setpoint.
Temperature range (1°F
increments) of cooling
setpoint.
Shown in 1/2°C
Minimum
Noncompressor On
Time
0620 3 0 - 15 Minimum number of
minutes non-compressor
(heat) equipment is on.
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 14
Minimum
Compressor On Time
0630 3 0 - 15 Minimum number of
minutes compressor is on.
Clock Format 0640 12 12, 24 12 - 12-hour clock format
24 - 24-hour clock format
Extended Fan On
Time Heat
0650 0 0, 30, 60,
90 or 120
Fan operation is extended
0, 30, 60, 90 or 120
seconds after call for heat
ends.
Only shown for nonvariable
speed indoor units.
Compressor Heat
Blower Off Delay
Profile
0651 5 0 - 5 0 - Disabled
1 - 0.5 min @ 35%
2 - 0.5 min @ 50%
3 - 1.5 min @ 50%
4 - 0.75 min @ 100%
5 - 1.5 min @ 100%
Only shown for variable
speed indoor units.
Extended Fan on
time control
0660 90 0, 30, 60,
90 or 120
Fan operation is extended
0, 30, 60, 90 or 120
seconds after call for cool
ends.
Only shown for nonvariable
speed indoor units.
Compressor Cool
Blower Off Delay
Profile
0661 5 0 - 5 0 - Disabled
1 - 0.5 min @ 35%
2 - 0.5 min @ 50%
3 - 1.5 min @ 50%
4 - 0.75 min @ 100%
5 - 1.5 min @ 100%
Only shown for variable
speed indoor units.
Compressor Heat
Fan On Delay Profile
0665 0 0, 1, 5,
10, 20,
30
0 - Disabled
1 - Enabled - 50% for 1
minute (V.S. only)
5 - 5 seconds
10 - 10 seconds
20 - 20 seconds
30 - 30 seconds
For Variable Speed indoor
units: choices are 0 and 1.
For Non-variable Speed
indoor units: choices are 0,
5, 10, 20, and 30.
Compressor Cool
Fan On Delay Profile
0667 0 0, 1, 5,
10, 20,
30
0 - Disabled
1 - Enabled - 50% for 1
minute (V.S. only)
5 - 5 seconds
10 - 10 seconds
20 - 20 seconds
30 - 30 seconds
For Variable Speed indoor
units: choices are 0 and 1.
For Non-variable Speed
indoor units: choices are 0,
5, 10, 20, and 30.
Keypad Lockout 0670 0 0, 1, 2 0 - Unlocked keypad
1 - Partially locked keypad
2 - Fully locked keypad
Unlocked - all functions are
available.
Partially locked - only
temperature up and down
keys and ability to enter and
modify installer setup mode
are available.
Fully locked - only ability to
enter and modify installer
setup mode are available.
Temperature Control
in Heat
0680 2 1, 2, 3 1 - Less aggressive
temperature control (could
cause temperature
undershoot)
2 - Standard temperature
control in heating
3 - More aggressive
temperature control (could
cause temperature
overshoot)
Applies to recovery ramp
and use of auxiliary heat
during recovery.
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
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15 69-2079—05
OPERATION
Using the Comfort Control
System and Fan Settings
The System default setting is Heat, unless no Heat stage
is discovered/configured. The fan default setting is Auto.
SYSTEM SETTINGS
Heat: Controls heating system.
Off: Heating and cooling are off.
Cool: Controls cooling system.
Auto: Automatically changes between heating and
cooling systems, depending on indoor temperature. (See
Installer Setup section.)
Em Heat: Compressor is locked out and auxiliary heat
cycles to maintain temperature (Used only for heat pump
systems with backup heat.) Maximum allowable
emergency heat stages is 3.
FAN SETTINGS
Pressing the fan key selects whether the indoor fan motor
runs in the On, Automatic, or Circulation mode. The fan
setting can be programmed into the Comfort Control
schedule for each period (Wake, Leave, Return, Sleep).
On: Fan runs continuously
Auto: Fan is automatically following the fan schedule.
(See Fan Schedule section for more information.)
Circ: Circulation control will provide a variable circulation
determined by the Adaptive Intelligent Circulation (AIC)
algorithm running the fan between 20% and 60% of the
time.
Temperature Control
in Cool
0690 2 1, 2, 3 1 - Less aggressive
temperature
control (could cause
temperature
undershoot)
2 - Standard temperature
control
in cooling
3 - More aggressive
temperature
control (could cause
temperature
overshoot)
Applies to recovery ramp
and use of cooling stages
during recovery.
Temperature Display
Offset
0700 0 -3, -2, -1,
0, 1, 2, 3
-3°F (-1.5°C)
-2°F (-1.0°C)
-1°F (-0.5°C)
0°F (0.0°C)
1°F (0.5°C)
2°F (1.0°C)
3°F (1.5°C)
Humidity Display
Offset
0701 0 -5, -4, -3,
- 2, -1, 0,
1, 2, 3, 4,
5
-5%
-4%
-3%
-2%
-1%
0%
1%
2%
3%
4%
5%
Reset Discovered
Device
0706 0 0, 1 0 - No
1- Yes
Will clear the equipment
change alert (Err 126 - see
Alert Code Addendum, form
18-HD32D2-1/69-2009) by
re-initializing Auto
Discovery
Restore Factory
Defaults
0710 0 0, 1 0 - No Comfort Control
reset
1 - Resets all Installer
Setup options to default
values and resets schedule
to default setting
(Energy Star).
Only the calendar setting
and time are retained.
Table 4. Installer Setup Menu
Selection
Installer Setup
Number (ISU)
Factory
Setting
Choices
CommentsOption Description

TCONT900AC43UA
Pub. No. 18-HD32D1-2
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LED Indication
An LED indicator is located in the upper right corner of the
Comfort Control. It is only visible when lighted:
• It indicates that there is an Alert.
• It indicates that the Comfort Control is in Discovery
mode.
LED Indication
FILTER INDICATION
The Comfort Control can track up to two filter timers by
total fan run time or calendar days. This feature can be
used to tell the homeowner when to replace the Furnace
filter or clean the Air Cleaner cells:
Select filter timer reset time:
Total Fan Run Time: the number of run time days for the
filter timer to count down from: 0, 10, 30, 60, 90, 120, 180,
270, or 365 days. (One run time day represents 24 hours
of continuous fan/system run time.)
Calendar Days: the number of days for the filter timer to
count down from: 0, 30, 60, 90, 120, 180, or 365 days. To
activate this feature, select a value other than 0
(disabled). See Owner’s Guide for more detailed
information.
Pre-programmed
Table 5 shows the Energy Star default program settings.
See Owner’s Guide for complete instructions on changing
the program.
Alert Code Numbers
The Comfort Control can receive Alert codes from any
communicating equipment via the ComfortLinkTM II bus.
The Comfort Control will illuminate the Red “Service” LED
and toggle between the main screen and a screen
showing the Alert code number. When multiple Alert
codes exist simultaneously, the display will cycle through
each code (showing a maximum of the 5 most recent
Alerts) and return to the main screen. See the Alert Code
Addendum (form 18-HD32D2-1/69-2009) for a listing of all
equipment Alert codes.
Equipment Damage Hazard. Minimum
compressor off-time is bypassed during Installer
System Test.
Avoid cycling compressor quickly. Observe compressor
protection period.
System Checkout
Installer System Test
The Installer System Test mode is used to test the
Comfort Control operation with HVAC equipment. See
Table 7. System configuration determines which tests are
available and the number of stages shown. While in
System Test mode, the minimum off time is bypassed.
The Installer Test is part of the Installer Setup options.
Enter Installer Setup screen and press the Down arrow
key for quick access to the test selection(s).
NOTE: Changing tests will turn equipment off.
NOTE: Entering Installer Setup will turn equipment off.
NOTE: NOTE: Charge AssistTM mode not available dur-
ing Installer System Tests.
NOTE: Test modes time out after 5 minutes.
Table 5. Energy Star Default Program Settings
Period Time
Heat
Setpoint
Cool
Setpoint
Fan
Setting
Wake 6:00 AM 70°F (21°C) 78°F (25.5°C) Auto
Leave 8:00 AM 62°F (16.5°C) 85°F (29.5°C) Auto
Return 6:00 PM 70°F (21°C) 78°F (25.5°C) Auto
Sleep 10:00 PM 62°F (16.5°C) 82°F (28°C) Auto
Table 6. Installer System Tests
Selection
Installer Setup
Number
Factory
Setting
Choices Comments
Option Description
Installer Test Cool Test 1 0 0, 1, 2, 3 0 - Cool is off
1 - Cool stage 1
2 - Cool stage 1, 2
3 - Cool stage 1, 2, 3
Not shown if ISU 0172 is
set to 3 or if ISU0174 is
set to 0.
If Discharge Air
Temperature Sensor is
available, Press the More
key to show the
Discharge Air
Temperature value.
Installer Test Fan Test 2 0 0, 1 0 - Fan is off
1 - Fan on
Not shown if ISU 0172 is
set to 3.
If Discharge Air
Temperature Sensor is
available, Press the More
key to show the
Discharge Air
Temperature value.

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17 69-2079—05
ADVANCED FEATURES
Adjustable Continuous Air Flow
The Continuous Fan air flow is user adjustable from 25%
to 100% in 5% increments either by entering the User
Setup menu or the Installer Setup menu (see Table 4, ISU
Number 0186).
NOTE: CONTINUOUS fan mode during COOLING
operation may not be appropriate in humid cli-
mates. If the indoor air exceeds 60% relative
humidity or simply feels uncomfortably humid, it
is recommended that the fan only be used in the
AUTO mode.
Control Response Rate
A set of more/ less aggressive Proportional-Integral
control constants can be chosen to increase/decrease the
responsiveness of the temperature control performance.
Choosing a more aggressive rate may cause
overshooting. Furthermore, selecting a less aggressive
rate may result in undershooting.
Cycle Rate
Cycle rate is the selected number of system cycles per
hour at 50% load. If the cycle rate were set to 3, each ON/
OFF cycle would be 20 minutes long when operating at
50% load. The total ON and/or OFF times depends on the
actual indoor space load. A shorter cycle rate may be
desired for Heating mode to maintain tighter control to
indoor setpoint. A longer cycle rate may be desired for
Cooling mode to allow the system to remove moisture
from the air and improve indoor comfort.
Auto Changeover
When the system mode is set to Auto, the control
automatically switches between heating and cooling
modes to maintain the desired comfort level.
Setpoint Deadband
The number of degrees separating Heating and Cooling
setpoints is user adjustable from 2 to 9 degrees. When
the control is set to Auto, and the cooling setpoint is
changed to a cooler setpoint, the heating setpoint will also
change to maintain the selected deadband. The same
action occurs when the Heating setpoint is changed to a
warmer temperature.
NOTE: The deadband is restricted to a range of 5 to 9 if
ISU 0380 is set to Integrated Temperature and
Humidity Control (ITHC).
Backlit Display
When continuous backlight is disabled, the liquid crystal
display will illuminate only when a touchscreen key is
pressed to improve visibility. The backlight stays on for 45
seconds after the last touch screen key press. When
continuous backlight is enabled, the liquid crystal display
will remain illuminated continuously. The display will dim
to half brightness 45 seconds after the last touch screen
key press.
Filter Reminders
The Comfort Control can track up to two filter timers by
total fan run time or calendar days. When the preset
timer(s) has expired to remind the homeowner that it is
time to change the filter(s), “Change” then “Filter” will
automatically flash. To reset either filter timer, simply
press the More key to access the filter timer value and
then press the Reset key. Once the timer has been reset,
Installer Test Heat Test 3 0 0, 1, 2, 3,
4
0 - Heat is off
1 - Heat stage 1
2 - Heat stage 1, 2
3 - Heat stage 1, 2, 3
4 - Heat stage 1, 2, 3, 4
Not shown if ISU 0176 is
set to 0.
If Discharge Air
Temperature Sensor is
available, Press the More
key to show the
Discharge Air
Temperature Air Value.
Installer Test
Emergency Heat
Test 4 0 0, 1, 2, 3 0 - EmHeat is off
1 - EmHeat stage 1
2 - EmHeat stage 1, 2
3 - EmHeat stage 1, 2, 3
If Discharge Air
Temperature Sensor is
available, Press the More
key to show the
Discharge Air
Temperature value.
Available only if heat
pump with auxiliary heat
is selected.
Installer Test
Humidifier
Test 5 0 0, 1 0 - Humidifier off
1 - Humidifier on
Not shown if ISU 0372 is
set to 0.
Fan will follow Hum
setting.
Installer Test
Dehumidification
Function
Test 6 0 0, 1 0 - Dehumidifier off
1 - Dehumidifier on
Not shown if ISU 0380 is
set to 0.
Fan will follow DeHum
setting.
Table 6. Installer System Tests
Selection
Installer Setup
Number
Factory
Setting
Choices Comments
Option Description

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 18
the filter timer value can be viewed at any time by simply
pressing the More key until the filter timer is displayed on
the screen.
NOTE: Both the filter timers are auto discoverable ISU
settings. If no ComfortLinkTM II communicating
filtering device has been discovered, the auto
discovered value will default to 0. To enable one
or both timers, change ISU 0500 and/or ISU
0501 to a value other than 0.
Fan Selections
Pressing the Fan key selects whether the indoor fan
motor runs in the On, Automatic, or Circulation mode. In
On mode, the fan motor runs continuously. The fan
automatically follows the fan schedule in Automatic mode.
Circulation control will provide a variable circulation
determined by the Adaptive Intelligent Circulation (AIC)
algorithm running the fan between 20% and 60% of the
time. Each schedule period (Wake, Leave, Return, Sleep)
can be programmed with a specific fan setting (On,
Automatic, or Circulation).
Screen Locked
Locking the control’s touch screen keys can help prevent
unwanted tampering with or changing of control settings.
The Comfort Control can either be fully locked or partially
locked. Both options continuously display “Screen
Locked” on the screen. Changing ISU Number 0670 to 0
will unlock the keys and “Screen Locked” will disappear.
Installer System Tests
The built in Installer System Test mode allows the servicer
to quickly and easily test the Comfort Control’s operation
with HVAC equipment and makes diagnostic procedures
a snap. System configuration determines which tests are
available and the corresponding number of stages shown
(see Table 7, Tests 1 - 6 for details).
Default Factory Settings
The Comfort Control is shipped with a set of factory
default settings. The factory default settings can be
restored at any time using the Installer Setup menu (see
Table 4, ISU Number 0710).
NOTE: Before you perform Auto-Discovery Mode (ISU
Number 0710), is it recommended that you
record all your user settings. All user setting
choices will be reset to factory defaults in Auto-
Discovery Mode.
Wait Indicator
“Wait” will be displayed when the setpoint is changed in
the direction of calling for additional system capacity or
the outdoor unit is in Charge AssistTM mode. “Wait”
indicates system time delays are being enforced, and the
control is adjusting to the new setting.
Calibrate Indoor Temperature
This option allows calibration of the room temperature
sensor. The selected number is number of degrees, plus
or minus, which will be added to the actual temperature.
The number can range between +3 and -3 degree in 1-
degree increments. Factory default is 0. The adjusted
value will be used as the temperature for both display and
control action.
Calibrate Indoor Humidity
This option allows calibration of the indoor humidity
sensor. The selected number is percent relative humidity,
plus or minus, which will be added to the actual indoor
humidity. The number can range between +5% and -5% in
1% increments. Factory default is 0. The adjusted value
will be used as the humidity for both display and control
action.
Outdoor Temperature Sensor
For accuracy, the initial reading of the outdoor
temperature sensor requires five minutes to stabilize. See
the Sensor Instructions for installation information.
NOTE: If the device is using an outdoor sensor for
control and the outdoor temperature sensor
becomes unavailable, the display will show
dashes “- -” and generate an Alert. If the device
is not using an outdoor sensor for control and
the outdoor temperature sensor becomes
unavailable, no outdoor value will be displayed.
The Comfort Control will not send an Alert.
Humidification
Indoor Humidification Control
This feature attempts to control the indoor humidity to the
user’s humidification setpoint using a humidifier. The
humidification setpoint can range between 10% and 60%
in 5% increments. When enabled, the default
humidification setpoint is 50%.
Frost Control
The Frost Control requires an outdoor sensor and a
humidifier. The Comfort Control calculates the possibility
of condensation or frost forming by using the outside
temperature and inside temperature to determine the
dewpoint. When the dewpoint could cause frost or
condensation, the humidification request will not be
honored.
SCHED HOLD CLOCK SCREEN MORE
TUE
TUE
PM
FAN
AUTO
SYSTEM
HEAT
Wait
Inside Set To
Humidity
THU
Hold Temperature
Until
CANCEL

TCONT900AC43UA
Pub. No. 18-HD32D1-2
19 69-2079—05
The Frost Setting can be accessed by pressing the More
key until the Frost Setting is displayed on the screen. It
has a value range of 0 to 10, with 0 representing glass
with poor insulation and 10 representing glass with
perfect insulation. If the factory setting (5), results in too
much condensation or frost on the windows, lower the
setting. When the air seems too dry, raise the setting.
Dehumidification
Integrated Temperature and Humidity Control
(ITHC)
The dehumidification control attempts to control the
indoor humidity to the user’s dehumidification setpoint by
running the compressor. The dehumidification setpoint
can be accessed by pressing the More key until the
dehumidification setpoint is displayed on the screen. The
setpoint can range between 40% and 80% in 5%
increments. When enabled, the default dehumidification
setpoint is 50%. In extremely high humidity conditions, the
Comfort Control keeps the compressor running for up to
3°F (-1.7°C) below the temperature setpoint. It does this
while trying to achieve the desired dehumidification
setpoint and balancing that with the temperature setpoint.
The maximum allowable dehumidification droop can be
selected in ISU 0383.
Trane Droop
Trane Droop is a feature that cycles the compressor on to
improve indoor comfort by removing moisture from the air.
The Droop cycle is activated when the indoor humidity is
above the user’s dehumidification setpoint. When this
function is active, the Comfort Control will control
temperature at 1 or 2 degrees F below the cooling
setpoint. The Droop cycle is deactivated when the indoor
humidity drops below the user’s dehumidification setpoint.
If the indoor humidity sensor fails, the droop logic will
always be enabled while in cooling mode.
Comfort-RTM Delay
When the indoor humidity is above the users
dehumidification setpoint, Comfort-RTM Delay will remove
humidity from the air by implementing a blower turn-on
delay of 15 or 30 seconds to “pre-chill” the coil. Comfort-
RTM Delay applies to non-variable speed indoor unit types
only.
Dehumidification Airflow
During any dehumidification control option, a lower speed
fan can be activated. The settings range from 80% to
100% in 5% increments (see Table 4, Installer Setup
number 0387). The default dehumidification airflow is
100%.
Trane Proprietary Humidity Control
When enabled, this feature will disable any blower off
delays and disable continuous fan mode when the indoor
humidity is above the dehumidification setpoint. This will
help prevent coil condensation from being evaporated
back into the air stream.
NOTE: This feature, ISU 0388, is not shown unless
some form of dehumidification control is
selected.
NOTE: Trane Proprietary Humidity Control does not
affect the fan operation when the fan setting at
the comfort control is in Auto or Circ Modes.
Special Heat Pump Features
Auxiliary Heat Lockout Temperature
When an outdoor temperature sensor has been
discovered/ enabled, none of the installed auxiliary heat
stages will turn on during heating operation above the
selected outdoor temperature. When the outdoor
temperature is less than the auxiliary heat lockout
temperature (ISU Number 0360), the Comfort Control
may cycle the indoor heat on and off to satisfy the load.
During defrost, this outdoor temperature setting is ignored
and the defrost heater balance point outdoor temperature
thresholds are used.
NOTE: For Dual Fuel applications, if the heat pump fails
to maintain heat while the outdoor temperature is
above the auxiliary lockout temperature, the fur-
nace will be used until the setpoint is reached, at
which time heat pump operation will resume.
Compressor Heat Lockout Temperature
When an outdoor temperature sensor has been
discovered/ enabled, only the installed auxiliary heat
stages will turn on during heating operation below the
selected outdoor temperature. When the outdoor
temperature is greater than the compressor heat lockout
temperature (ISU Number 0350), the heat pump attempts
to satisfy the load.
If the heat pump can not satisfy the load and the outdoor
temperature is less than the compressor lockout
temperature (ISU Number 0350), the Comfort Control will
transition to auxiliary heat operation and will turn off the
heat pump. During defrost, this outdoor temperature
setting is ignored and the defrost heater balance point
outdoor temperature thresholds are used.
NOTE: There is a 5°F deadband between the Compres-
sor and auxiliary heat lockout temperatures.
Operation in Heat Mode
When the outdoor temperature is below the compressor
lockout temperature, only the auxiliary heat operates.
When the outdoor temperature is above the auxiliary
lockout temperature, only the Compressor operates. See
Figure 9. When the outdoor temperature is between the
two temperatures, both the Compressor and auxiliary
heat operate.
Fig. 9. Heat Pump Operation with Lockout
Temperatures Set.
Defrost Heater Balance Point Control
When an outdoor temperature sensor has been
discovered/ enabled, a separate outdoor temperature
turn-on threshold can be set for each installed heater
stage during defrost in Installer Setup Numbers 0361 -
35
COMPRESSOR
LOCKOUT
TEMPERATURE
AUXILIARY
LOCKOUT
TEMPERATURE
COMPRESSOR ONLY
BOTH COMPRESSOR AND
AUXILIARY HEAT
AUXILIARY ONLY
50
OUTDOOR TEMPERATURE

TCONT900AC43UA
Pub. No. 18-HD32D1-2
69-2079—05 20
0363. If the balance point for a particular heater stage is
disabled, that heater stage will be used during every
defrost cycle independent of the outdoor temperature.
NOTE: NOTE: If the outdoor sensor is no longer report-
ing, all available heater stages will be used dur-
ing defrost.
When an outdoor temperature sensor has not been
discovered/enabled, the stage or combination of stages to
be used during defrost can be set in Installer Setup
Number 0364.
Operation in Emergency Heat Mode
When the Comfort Control is placed in Emergency Heat
mode, the compressor and auxiliary lockout features are
turned off. In the Emergency Heat mode, the compressor
is locked out and only the auxiliary heat operates. The
Comfort Control is capable of controlling up to a maximum
of three Emergency Heat stages.
Heat Pump with Fossil Fuel Heat (Dual Fuel) and
Outdoor Temperature Sensor
In this operation, there is no external fossil fuel kit (dual
fuel kit) installed; the Comfort Control controls this
function. During the transition between Furnace and heat
pump operation, there is a minimum Comfort Control time
delay of 45 seconds between the Furnace turning off and
the heat pump turning on and 0 seconds between the
heat pump turning off and the Furnace turning on.
NOTE: If the outdoor is missing or no longer reporting,
the control algorithm will revert back to a fossil
fuel only application.
For non-communicating equipment, configure the Comfort
Control by:
1. Choose Heat Pump Application in Installer Setup
Number 0172.
2. Choose Fossil Fuel Option as the backup heat
source in Installer Setup Number 0200.
3. Outdoor Temperature Sensor for Control Option
is automatically chosen in Installer Setup Number
0342.
4. Choose appropriate Dual Fuel Heat Pump Control
in Installer Setup Number 0345.
NOTE: If the heat pump fails to maintain heat while the
outdoor temperature is above the auxiliary lock-
out temperature, the Furnace will be used until
the setpoint is reached, at which time heat pump
operation will resume.
5. Choose appropriate Compressor Lockout Tem-
perature in Installer Setup Number 0350.
6. If heat pump auxiliary lockout was selected in
Installer Setup Number 0345, choose appropriate
Heat Pump Auxiliary Lockout Temperature in
Installer Setup Number 0360.
7. Choose appropriate Defrost Balance Point Tem-
peratures in Installer Setup Numbers 0361 - 0363.
Heat Pump with Electric Auxiliary (Backup) Heat
and Outdoor Temperature Sensor
For non-communicating equipment, configure the Comfort
Control by:
1. Choose Heat Pump Application in Installer Setup
2. Choose Electric Option as the Auxiliary (Backup)
Heat Source in Installer Setup Number 0200.
3. Choose appropriate Outdoor Temperature Sensor
for Control Option in Installer Setup Number 0342.
4. If Outdoor Temperature Sensor was discovered/
enabled in Installer Setup Number 0342, choose
appropriate Compressor Lockout Temperature
in Installer Setup Number 0350.
5. If Outdoor Temperature Sensor was discovered/
enabled in Installer Setup Number 0342, choose
appropriate Heat Pump Auxiliary Lockout
Temperature in Installer Setup Number 0360.
6. If Outdoor Temperature Sensor was discovered/
enabled in Installer Setup Number 0342, choose
appropriate Defrost Balance Point Temperatures
in Installer Setup Numbers 0361 - 0363.
TROUBLESHOOTING GUIDE
Refer to Table 8 for troubleshooting information.
Table 7. Troubleshooting Information
Symptom Possible Cause Action
Red service LED is illuminated
and the display alternates
between Home screen and Alert
Code screen.
Alert Code present Refer to the Alert Code Addendum (form
18-HD32D2-1/69-2009).
Display will not come on. 1. Blown fuse or tripped circuit
breaker.
2. Indoor unit power switch OFF.
3. Indoor unit blower
compartment door or panel loose
or not properly installed.
4. Wire broken/shorted; or R and
D or B and D are reversed.
1. Replace fuse or reset breaker.
2. Turn power switch to ON.
3. Replace door panel in proper position
to engage safety interlock or door switch
on furnace.
4. Check R, B, D wiring.
Indoor temperature display is
incorrect.
Temperature display needs
calibration.
Calibrate Sensor - ISU 0700
Indoor humidity display is
incorrect.
Indoor humidity display needs
calibration.
Calibrate Sensor - ISU 0701