Carrier A07051 User manual

T C --- PA C , T C --- N A C
T C --- P H P, T C --- N H P
ComforttSeries Thermostats
Installation Instructions
A07051 A07050
Comfort Series Comfort Series
Programmable Thermostat Non ---Programmable Thermostat
NOTE: Read the entire instruction manual before starting the installation.

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TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS 3....................................
INTRODUCTION 4..............................................
INSTALLATION CONSIDERATIONS 4..............................
INSTALLATION 5...............................................
Step 1 — Thermostat Location 5...................................
Step 2 — Install Thermostat 6......................................
Step 3 — Set Thermostat Configuration 10...........................
Step 4 — Check Thermostat Operation 18............................
FEATURES AND ACCESSORIES 19................................
OPERATIONAL AND CONNECTION INFORMATION 21..............
WIRING DIAGRAMS 24..........................................
THERMOSTAT CONFIGURATION RECORD 25......................
SAFETY CONSIDERATIONS
Read and follow manufacturer instructions carefully. Follow all local electrical
codes during installation. All wiring must conform to local and national electrical
codes. Improper wiring or installation may damage thermostat.
Recognize safety information. This is the safety--alert symbol . When you see
this symbol on the equipment and in the instruction manual, be alert to the
potential for personal injury.
Understand the signal words DANGER,WARNING,andCAUTION.These
words are used with the safety--alert symbol. DANGER identifies the most
serious hazards which will result in severe personal injury or death. WARNING

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signifies a hazard which could result in personal injury or death. CAUTION is
used to identify unsafe practices which may result in minor personal injury or
product and property damage. NOTE is used to highlight suggestions which will
result in enhanced installation, reliability, or operation.
INTRODUCTION
Carrier’s ComforttSeries programmable thermostats are wall--mounted,
low--voltage thermostats which maintain room temperature by controlling the
operation of a heating and/or air conditioning system. Both heat pump and air
conditioner models are available, each in programmable and non--programmable
versions. A variety of features are provided including battery operation, separate
heating and cooling setpoints, auto changeover, keypad lockout, backlighting,
and built--in installer test. Programming features include 7--day (all days the
same) and 5/2 (Mon--Fri and Sat--Sun) with 2 or 4 periods per day.
This Installation Instruction covers installation, configuration, and startup of all
four versions of the Comfort Series line of thermostats. For operational details,
consult the Owner’s Manual for the specific thermostat you are installing.
INSTALLATION CONSIDERATIONS
Models
There are four models in the Comfort Series: programmable and
non--programmable, AC and HP. Models TC--PAC and TC--NAC are designed for
AC systems, controlling one stage of cooling and one stage of heating. They will not
operate a heat pump. Models TC--PHP and TC--NHP are designed for HP systems,
controlling one stage of cooling and two stages of heating. They can be converted to
AC operation. Select the appropriate model for the intended application.

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Power
All Comfort Series models are dual powered. They can operate from batteries or
24VAC power. Operation from 24VAC is preferred if available. Battery
operation is used when there are not enough wires to support 24VAC operation
or when “armchair programming” is desired. For an AC system, 5 wires are
needed for 24VAC operation and as few as 2 wires are sufficient for battery
operation. For a HP system, 6 wires are needed for 24VAC operation and 5 wires
are sufficient for battery operation. When battery operation is used, the C
terminal does not need to be connected.
Provision is also made for separate heating and cooling transformers via separable
Rc and Rh terminals which are connected via factory--installed jumper wire.
INSTALLATION
Step 1 — Thermostat Location
SApproximately 5 ft (1.5m) from floor.
SClose to or in a frequently used room, preferably on an inside
partitioning wall.
SOn a section of wall without pipes or duct work.
Thermostat should NOT be mounted
SClose to a window, on an outside wall, or next to a door leading to the
outside.
SExposed to direct light or heat from the sun, a lamp, fireplace, or other
temperature--radiating objects which could cause a false reading.
SClose to or in direct airflow from supply registers and return--air
registers.

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SIn areas with poor air circulation, such as behind a door or in an
alcove.
Step 2 — Install Thermostat
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installing thermostat, turn off all power to equipment.
There may be more than 1 power disconnect.
!WARNING
1. Turn OFF all power to unit.
2. If an existing thermostat is being replaced:
a. Remove existing thermostat from wall.
b. Disconnect wires from existing thermostat, 1 at a time. Be careful not
to allow wires to fall back into the wall.
c. As each wire is disconnected, record wire color and terminal marking.
d. Discard or recycle old thermostat.

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ENVIRONMENTAL HAZARD
Failure to follow this caution may result in environmental
damage.
Mercury is a hazardous waste. Federal regulations require that
Mercury be disposed of properly.
CAUTION
!
3. Open thermostat (mounting base) to expose mounting holes. The base
can be removed to simplify mounting. Press the thumb release at the top
of the thermostat and snap apart carefully to separate mounting base from
remainder of thermostat.
4. Route thermostat wires through large hole in mounting base. Level mounting
base against wall (for aesthetic value only—thermostat need not be level for
proper operation) and mark wall through 2 mounting holes. See Fig. 1.
A07153
Fig. 1 -- Backplate Mounting

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5. Drill two 3/16--in. mounting holes in wall where marked.
6. Secure mounting base to wall with 2 anchors and screws provided
(additional anchoring holes available for more secure mounting if needed)
making sure all wires extend through hole in mounting base.
7. Adjust length and routing of each wire to reach proper terminal and
connector block on mounting base with 1/4 in. of extra wire. Strip only
1/4 in. of insulation from each wire to prevent adjacent wires from
shorting together when connected. See Fig. 2.
A07155
Fig. 2 -- Secure Wires to Terminal Strip
8. Match and connect equipment wires to proper terminals of the connector
blocks (see Fig. 3). If there are separate 24VAC transformers, one in the
indoor unit and one in the outdoor unit, connect the common of each to the
C terminal. Remove factory--installed jumper wire from Rc and Rh terminals.
Connect the R from the indoor unit to the Rh terminal. Connect the R from
the outdoor unit to the Rc terminal. Then the W and G signals are taken from
the Rh power and the Y and O signals are taken from the Rc power.

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O/B - reversing valve
Not used
Rc - 24 VAC, from cooling equipmen
t
Rh - 24 VAC, from heating equipmen
t
W - Heating
C - Common 24 VAC
G - Fan
Y - Cooling
A07159
Fig. 3 -- Terminal Designations
ELECTRICAL OPERATION HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
Improper wiring or installation may damage the thermostat.
Check to make sure wiring is correct before proceeding with
installation or turning on unit.
CAUTION
!
9. Push any excess wire into wall and against mounting base. Seal hole in
wall to prevent air leaks. Leaks can affect operation.
10. Snap case back together. Attach thermostat to backplate by inserting tab
on bottom edge and hinging up until top snap secures. See Fig. 4.

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A07157
Fig. 4 -- Attach Comfort Series Programmable Thermostat
11. Close thermostat assembly making sure pins on back of circuit board
align with sockets in connector.
12. Turn ON power to unit.
When power is applied, all display icons are lit for 2 seconds to test the display.
Following this, the equipment type for which the thermostat is configured is
displayed for an additional 2 seconds. It will be one of HP, AC, H, PH, PC or C (see
explanation under Step 3, Option 01 below). A HP thermostat configured to operate
an AC (see Option 1 below) will display AC. An AC thermostat cannot display HP.
NOTE: If a common wire has not been connected, two AA batteries must be
used to power the thermostat.
Step 3 — Set Thermostat Configuration
Configuration options enable the installer to configure the thermostat for a particular
installation. Most are not presented to the homeowner and therefore must be properly

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set by the installer. (Only those marked with an asterisk * below are available to the
homeowner.) Following is a list of the options available, an explanation of their
function, and their factory default settings. Not all numbers are used in the Comfort
Series because not all options are available in this series -- and numbering is
consistent across the TB, TC, and TP thermostat lines.
Configuration Options -- Summary:
Option 01 -- Equipment type
Option 03* -- Fahrenheit/Centigrade
Option 04 -- Fan (G) on with W output
Option 07 -- Zoning
Option 10 -- Reversing valve
Option 11 -- Minimum deadband between heating and cooling setpoints
Option 12 -- Smart Recovery (programmable models only)
Option 13 -- Room air temperature offset adjustment
Option 15 -- Auto Changeover availability
Option 16 -- Maximum cycles per hour
Option 17 -- Time between equipment stages
Option 18* -- Continuous backlighting
Option 21* -- Keypad lockout
Option 24* -- Programmable/non--programmable (programmable models only)
Option 25* -- Number of programmable periods per day
Option 26 -- Minimum cooling setpoint
Option 27 -- Maximum heating setpoint
Option 99 -- Reset to factory defaults
Those options marked with an asterisk are also adjustable by the homeowner.
See Owner’s Manual for further information.

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To Enter the Configuration Mode:
Press and hold the FAN key for about 10 seconds until the display changes so
that only two pairs of digits are showing. The left (programmable version) or the
large upper (non--programmable version) display shows the configuration
number and the right (programmable version) or small lower
(non--programmable version) shows the configuration setting. Configuration
number will be flashing which means it can be adjusted using the UP and
DOWN keys. To cause the opposite pair to flash (to be adjustable), press the
MODE key. Successive presses of the MODE key alternate between the
configuration number and the configuration setting. To exit the configuration
mode, press the FAN key. If no key is pressed for 3 minutes, the configuration
mode will automatically exit, returning the thermostat to normal operation.
Configuration Options -- Selection:
Option 01 -- Equipment type
Selections: with HP thermostat: HP, AC, H, C, PH or PC
with AC thermostat: AC, H, C or PC
PC and PH are only available on non--programmable models.
Meanings:
PC or PH selects PTAC units (Packaged Terminal Air Conditioners) which
are used in motel rooms and other rented spaces. When this option is
selected, the display shows only the setpoint, not the room temperature.
Also the compressor timeguard is disabled, allowing the compressor to
turn on immediately when a demand is established.
HP or PH controls 1 speed heat pump with 1 stage of aux heat.
AC or PC controls 1 speed air conditioner with 1 stage of heat.
H operates a heat only system: furnace or fan coil only; no outdoor unit.

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C operates a cool only system: outdoor AC unit with an indoor fan coil; no strip
heater support.
Note that this option allows a HP thermostat to be converted to control an AC
system.
Option 03 -- Fahrenheit/Centigrade
Selections:
F = Fahrenheit — Default is Fahrenheit.
C = Centigrade.
Selects temperature measurement units.
Option 04 -- Fan (G) ON with W output
Selections:
OF = G not energized with W — This is default.
ON = G energized with W.
This selection determines whether the fan (G) is to be ON or OFF when the W
(furnace or strip heat) is ON. Furnaces and fan coils which manage their own
blowers do not require a separate G signal. Some auxiliary heaters require a
separate G signal to operate the blower when W is applied.
Option 07 -- Zoning
Selections:
OF = non--zoned system — This is default.
ON = zoned system.
ON disables thermostat’s internal timers which are not needed with zoning
system controls. Must be set to OF for non--zoned systems.

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Option 10 -- Reversing valve
This selection is only available on heat pump systems. “O” terminal can be
configured to be energized in either heating mode or in cooling mode, depending
on heat pump operation. “O” is used to describe a heat pump system that
energizes its reversing valve in cooling. “B” is used to describe a heat pump
system that energized its reversing valve in heating.
H — Reversing valve output (O/W2/B) is energized when HEAT mode is
selected.
C — Reversing valve output (O/W2/B) is energized when COOL mode is
selected.
Default is C.
Option 11 -- Minimum Deadband Between Heating And Cooling
Selections:
01 through 06 — Default is 02.
Sets the minimum allowable number of degrees between heating and cooling
setpoints. One setpoint will “push” the other to maintain this difference.
Option 12 -- Smart Recovery (programmable model only)
Selections:
OF, 30, 60, 90 — Default is 90.
Smart Recovery OF means setpoints change immediately at setback recovery
time. Thirty, 60, or 90 selects the number of minutes recovery starts before
programmed recovery time. Recovery takes place smoothly during the selected
recovery time, ending at the recovery time and temperature which is
programmed. If the setpoint is changed during smart recovery, the smart
recovery is cancelled and the new setpoint is effective immediately. Not available
with non--programmable thermostats.

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Option 13 -- Room Air Temperature Offset
Selections:
--5to5_F—Defaultis0.
This option selects the number of degrees F to be added to the displayed
temperature to calibrate or deliberately miscalibrate the measured room
temperature.
Option 15 -- Auto Changeover Availability
Selections:
ON—Thisisdefault.
OF
ON allows automatic changeover between heating and cooling as demand
requires. OF maintains either heating or cooling mode only. Auto changeover is
not available when PH, PC, H or C is selected under Option 1.
Option 16 -- Maximum Cycles Per Hour
Selections:
2, 4, or 6 — Default is 4.
The maximum cycle rate is limited by internal timers to the selected number of
cycles per hour. Selection of a higher number causes faster cycling resulting in
more constant room temperature.
Option 17 -- Minimum Time Between Equipment Stages
Selections:
10, 15, 20, 25 — Default is 15.
When there are two stages of heat available, this is the amount of time the first
stage must operate before the second stage can turn on. With heat pumps, longer

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times can reduce the amount of auxiliary heat used. Not available with AC
thermostats.
Option 18 -- Backlight Configuration
Selections:
ON, OF — Default is OF.
When ON is selected and the thermostat is not battery operated a low level
continuous display backlight is always on. With OF selected, the backlight is
only on for a short time after the door is opened or a key is pressed. Continuous
backlight is not available with battery operation.
Option 21 -- Keypad Lockout
Selections:
ON, OF — Default is OF.
With OF selected, the keypad cannot be locked. With ON selected the keypad
will be locked and can be unlocked by simultaneously pressing the UP and
DOWN keys for 5 seconds. Once unlocked, it will relock 2 minutes after the last
keypad press. A “lock” icon is displayed while it is locked.
Option 24 -- Programmable/Non--Programmable (programmable model only)
Selections:
P, nP — Default is P.
This option is only available on programmable models, allowing programming
to be disabled when nP is selected. The clock is displayed, but the program
schedule, the HOLD and TEMPORARY HOLD functions are disabled.
Option 25 -- Number of Programmable Periods (programmable model only)
Selections:
2, 4 — Default is 4.

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Selecting 2 allows 2 programming periods, P1 and P2, per day. Selecting 4
allows periods P1, P2 , P3, and P4. Not available with non--programmable
thermostats.
Option 26 -- Minimum Cooling Setpoint
Selections:
52_to 90_— Default is 52_F.
Sets the lowest cooling setpoint available to the user.
Option 27 -- Maximum Heating Setpoint
Selections:
50_Fto88_F—Defaultis88_F.
Sets the highest heating setpoint available to the user.
Option 99 -- Reset to Factory Defaults
Selection:
See below — There is no default.
Use this capability to reset the thermostat to “out of the box” conditions.
NOTE: All configuration settings, program settings, clock, and day which have
been manually entered will be lost!
When this option is selected, the configuration number (99), will appear on the
left and 10 will appear on the right. To perform the reset, first use the MODE key
to make the 10 flash. Then press and hold the DOWN key. The 10 will start
counting down toward zero. If the DOWN key is kept pressed until the count
reaches zero, the reset will be performed. If the DOWN key is released early, the
number will return to 10 and the reset will not occur.

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Step 4 — Check Thermostat Operation
The Comfort Series thermostats have a built--in installer test capability. Use it to
check thermostat and equipment operation without delays or setpoint
adjustments to force heating or cooling.
To enter the Installer Test mode, use the same process as is used to enter Installer
Configuration, only hold the FAN key longer. More specifically, press and hold
the FAN for about 15 seconds until the display reads In on the left and St on the
right for the programmable model, or InS in the smaller display for the
non--programmable model. The MODE will be OFF. The MODE key (upper
left) can now be used to select heat, cool, or emergency heat, if this is a HP
thermostat. Selecting one of the available modes will immediately command the
equipment to turn on in that mode. It will run for 3 minutes and then return the
mode to off. With HP thermostats (having 2 stages of heating), the test will run
for 3 minutes on each stage. If the thermostat is programmable, the clock display
counts down from 180 seconds while each stage operates. Changing the mode to
OFF will terminate any running test immediately.
During any test, the display icons will be displayed the same as for normal
operation of that stage, as follows:
SELECTED MODE DISPLAY ICONS
off off
cool cool on
heat heat on, aux heat on
Em Heat aux heat on
To terminate the Installer Test mode press the DONE or FAN button. If the
thermostat is left in Installer Test mode, it will revert back to normal operation
after 15 minutes.

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Checklist
1. Run equipment through several heating and cooling cycles to ensure
proper operation. To operate the thermostat in its normal operating mode,
consult the Owner’s Manual.
2. If the equipment is to be left in operation, the setpoints, operating mode,
and possibly program schedule must be properly selected.
3. Put away tools and instruments and clean up debris.
4. Review and leave Owner’s Guide with owner.
FEATURES AND ACCESSORIES
Home, Away, Sleep (programmable models only)
This feature provides three button selections which select from three
predetermined pairs of heat and cool setpoints. In programmed versions, one of
these three choices can be selected for any programmed period. To change these
settings, a temperature is first selected and then the key pressed and held, similar
to setting stations on a push--button radio. See Owner’s Manual for details.
Clock (programmable models only)
Without batteries the clock will continue to operate for 8 hours while power is
removed. With batteries, the clock operates until the end of the battery life.
Batteries
Battery operation is available for installations where there is no common (C)
wire available at the thermostat or where operation is to continue while the
thermostat is removed from the wall, usually to facilitate remote (armchair)
programming. For battery operation, install two alkaline AA batteries. The
thermostat is designed to operate up to one year on a set of batteries. A battery
indicator on the display warns when battery replacement is needed. See

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Homeowners Guide for details. If batteries are installed and the thermostat is
operated from 24VAC power, battery operation will occur only when 24VAC
power is not present. The changeover between 24VAC power and battery power
is automatic.
Display Lighting
The display has two levels of lighting, high level and low level. High level
lighting comes on for 10 seconds when the door is opened and/or buttons are
being pressed with 24VAC and with batteries. Low level lighting is only
available if the thermostat is operated from 24VAC. It is not available with
batteries. The low level can be selected (see Option 18) for continuous backlight.
Door Switch
When the door is opened, the display changes from its normal operation view.
The large temperature display disappears so it will be available for other user
functions. If the door is left open for 3 minutes, the display reverts to normal
operation.
Mounting Options
For those installations requiring it, mounting hole locations for the
programmable model are spaced to fit either a horizontal or vertical junction box.
Mounting hole locations for the non--programmable are spaced to fit a horizontal
junction box.
Defrost Operation
In a HP installation with the “O” selection of Option 10, the thermostat allows all
defrost cycles to run to completion before turning off the compressor. It does this
by sensing a 24VAC signal on the O line which it did not produce. This occurs
while the HP is defrosting. As long as this O signal is present, the thermostat will
keep the Y output on, even if it is satisfied, thus allowing the defrost cycle to