Carrier 33CS, Debonair 33CS250-01 Installation, Start-up, And Operating Instructions Manual

Commercial Programmable Thermostat

Installation, Start-Up, and

Operating Instructions

Part Number 33CS250-01

Debonair®

33CS

CONTENTS

Page

SAFETY CONSIDERATIONS ...................... 1

GENERAL ........................................ 1

INSTALLATION ................................. 1-6

Select Thermostat Location ...................... 1

Install Thermostat ................................ 1

Set Clock......................................... 3

Heat Pump Configuration ........................ 3

Configure Advanced Setup....................... 3

Install Accessories ............................... 4

Program Thermostat Schedules..................5

Calibrate Sensor ................................. 6

Check Thermostat Operation.....................6

Final Checklist ................................... 6

OPERATION.................................... 6-8

Auto-Changeover ................................6

Two-Stage Operation............................. 6

Clock Backup .................................... 6

Fan Operation....................................6

Emergency Heat ................................. 6

Electric Heat ..................................... 7

Holiday Mode .................................... 7

Remote Temperature Sensor ..................... 7

Keypad Lock ..................................... 7

Dry Contact Switch/External Control .............7

10-Watt Resistor ................................. 7

TROUBLESHOOTING............................. 9

IMPORTANT Read entire instructions before starting the
installation.

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 the safety alert symbol is present on equipment
or in the instruction manual, be alert to the potential for person­al injury.

Understand the signal words DANGER, WARNING, and
CAUTION. 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 signifies a haz­ard which could result in personal injury or death. CAUTION
is used to identify unsafe practices which would result in minor
personal injury or property damage.

GENERAL

The 7-day, commercial, programmable thermostats are
wall-mounted, low-voltage thermostats which maintain room
temperature by controlling the operation of an HVAC (Heating,
Ventilation, and Air Conditioning) system. Separate heating
and cooling set points and auto-changeover capability allow
occupied and unoccupied programming for energy savings.

All thermostats allow up to 4 time/temperature settings to
be programmed per 24-hour period. Each thermostat stores
programs for 7 independent days. Batteries are not required.
During power interruption the internal NEVERLOST™ mem­ory stores programmed schedules for an unlimited time while
the clock continues to run for at least 48 hours.

The thermostat can be configured to accept several different
equipment configurations, including heat pump operation.

NOTE: The thermostat is not factory-configured for use in heat
pump applications. The advanced setup must be performed to
configure the thermostat for use with heat pump units.

INSTALLATION

Select Thermostat Location —

be mounted:

• approximately 5 ft from the floor

• close to or in a frequently used room, preferably on an

inside partitioning wall

• on a section of wall without pipes or ductwork

• where temperature operating limits are within 41 to 104 F

(5 to 40 C)

• where humidity operating range is within 0 to 95% rela-

tive humidity, non-condensing
The thermostat should NOT be mounted:

• close to a window, on an outside wall, or next to a door

leading to the outside

• where exposed to direct light and heat from a lamp, the

sun, a fireplace, or any other temperature-radiating

object which may cause a false reading

• close to or in direct airflow from supply registers or

return air grilles

• in areas with poor air circulation (such as behind a door

or in an alcove)

The thermostat should

Install Thermostat

Before installing thermostat, turn off all power to the unit.
There may be more than one power disconnect. Electrical
shock can cause injury or death.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 1 4
Ta b 1 a 1 3a

PC 111 Catalog No. 533-317 Printed in U.S.A. Form 33CS-12SI Pg 1 1204 12-97 Replaces: New

1. Turn off all power to unit.

2. If an existing thermostat is being replaced:
a. Remove existing thermostat from the wall.
b. Disconnect wires from existing thermostat. Do not

allow wires to fall back into the wall. As each wire
is disconnected, record wire color and terminal
connection.

c. Discard or recycle old thermostat.

NOTE: Mercury is a hazardous waste and must be
disposed of properly.

3. Remove the thermostat cover from wall plate (mounting
base) to expose mounting holes. See Fig. 1. With the ther­mostat facing forward, press the back plate on the left
hand side top corner to release the two prongs holding on
the cover. Pull off the cover when the prongs have been
disengaged.

4. Route thermostat wires through large hole in mounting
base. Remove outer sheath from wires for added flexibili­ty. Standard solid or multi-conductor thermostat wire
should be used from the thermostat to the unit. Size and
length considerations are as follows: for a maximum dis­tance from unit of 36 ft, use 22 AWG (American Wire
Gage) wire; for a maximum distance from unit of 100 ft,
use 18 AWG wire.

7. Secure mounting base to wall with 2 screws and anchors
provided. Ensure all wires exit through hole in mounting
base.

8. Adjust wire length and routing to allow proper closure of
the thermostat. Strip each wire at the end no more than

1

/4-in. to prevent adjacent wires from shorting together.
Match and connect wires to terminals on the thermostat.
See Fig. 2-4 and Table 1.

Improper wiring or installation may cause damage to the
thermostat. Check to ensure wiring is correct before pro­ceeding with installation of unit.

9. Push excess wiring into wall. Seal hole in wall to prevent
drafts.

10. Re-attach thermostat cover to back plate by aligning the
top two prongs of the back plate in the vertical groove of
the top cover and then snapping the cover onto the back
plate.

11. Turn on power to unit. The thermostat will receive power
from the unit. The thermostat will be powered by 24 v,
nominal (18 to 30 vac). Terminals R (+ 24 v), W1/O/B
(first stage heat or reversing valve), Y1 (first stage cool­ing), and G (fan relay) will always be connected. Some
applications will use C (common), Y2 (second stage
cooling), or W2 (second stage heating).

Fig. 1 — Thermostat Mounting

5. Level mounting base against wall and mark wall through
the 2 mounting holes in base.

6. Drill two

3

/16-in. mounting holes in wall where marked.

Be careful not to drill into wiring in wall. Electrical shock
could result.

1204

W2 — Second-Stage Heat
Y2 — Second-Stage

RS2 — Second Remote

RS+5 — +5 vdc
RS1 — Remote Sensor
RS GND — Ground

Compressor

Sensor (Not Used)

→ Fig. 2 — Thermostat Wiring

2

LEGEND

W1/O/B — First-Stage Heat or

Y1 — First-Stage Compressor
G—Fan
W3/ECO — Economizer
CK1 — Dry Contact
CK2 — Dry Contact Ground
R—24 vac Transformer
C—24 vac Transformer

Reversing Valve

Common

THERMOSTAT

B
O

G

W2Y2R

→

(Single-Stage Cooling and Two-Stage Heat Units)

W2Y2R

→

(Two-Stage Cooling and Two-Stage Heat Units)

W1

THERMOSTAT

B
O

W1

C

Y1

24 VAC COMMON

COMPRESSOR RELAY

1st STAGE HEAT CIRCUIT

2nd STAGE HEAT CIRCUIT

Fig. 3 — Typical Wiring

G

C

Y1

24 VAC COMMON

COMPRESSOR RELAY

1st STAGE HEAT CIRCUIT

2nd STAGE COMPRESSOR RELAY

2nd STAGE HEAT CIRCUIT

Fig. 4 — Typical Wiring

FAN RELAY

24 VAC RETURN

FAN RELAY

24 VAC RETURN

Table 1 — Thermostat Wiring Terminations

EXISTING

WIRE

DESIGNATION

GorF Fan G

Y1, Y, or C Cooling Y1

W1,W,orH Heating W1/O/B

Rh,R,M,Vr,orA Power (24 v) R

C Common C*

O/B Reversing Valve W1/O/B†

Y2 Second Stage Cooling Y2

W2 Second Stage Heating W2

RS+5 Remote Sensor (5 vdc) RS+5

RS Remote Sensor Signal RS1

RS G Remote Sensor Ground RS GND

CK1 Dry Contact Switch CK1
CK2 Dry Contact Ground CK2

*Terminal C may not be used in all applications.

†Used on Heat Pump applications only.

FUNCTION

TERMINAL

CONNECTION

TYPICAL

UNIT

TYPICAL

UNIT

L

E

C

G

Y1

O

W1

R

Y2

W2

L

E

C

G

Y1

O

W1

R

Y2

W2

Set Clock — The Set Clock button allows the user to

change the time and day displayed on the thermostat. Press the
Set Clock button. The current time will blink on and off. Press
the UP ARROW and DOWN ARROW buttons until the cor­rect time is shown. Hold down the buttons to quickly move
through the time display. Press and hold the Fan button while
pressing the UP or DOWN ARROW buttons to scroll through
by hours. The AM and PM annunciators will automatically
change. To ensure the schedules are properly followed, make
sure that AM or PM is correct for the time chosen. When the
correct time is shown, press the Mode button to modify the day
of the week. The current day will blink on and off. Press the UP
ARROW and DOWN ARROW buttons until the correct day is
shown. Press the Set Clock button again to exit the Set Time
mode.

Heat Pump Configuration — To configure the ther-

mostat for heat pump operation, Advanced Setup Steps 3 (Heat
Pump Operation) and 4 (Reversing Valve Polarity) must be
configured correctly. See the Configure Advanced Setup sec­tion for information on configuring these options.

NOTE: Some large commercial rooftop heat pump units
(50HJQ,TJQ,EJQ) must be configured with Advanced Setup
Step 3 (Heat Pump Operation) set to OFF. Refer to the base
unit instructions for more information.

Configure Advanced Setup — To ent er i nto the ad -

vanced setup screens of the thermostat, press the Mode and
Program buttons at the same time. The Advanced Setup Step
number is shown in the top right corner of the thermostat
screen. Use the Mode button to advance through the steps.
There are 18 Advanced Setup Steps. See Table 2. Press the Pro­gram button at any time to exit the Advanced Setup mode.

NOTE: Advanced Setup Steps 1 and 2 are configured with the
Set Clock button, and are not accessed through the advanced
setup screens.

Table 2 — Advanced Setup Configuration

STEP DESCRIPTION RANGE DEFAULT

1* Time of Day

2* Day of the Week

3 Heat Pump Off/On Off

4

5 Electric Heat Off/On Off
6 Deadband 1 - 6 F 2 F

7

8 Cycles per Hour d, d1, 2 - 6 6

9 Fan Purge Timer 0:00 - 3:00 0:00
10 Thermoglow™ Backlight Off/On On
11 Economizer Output NO/NC NO

12

13

14 Soft Start 0 - 99 0
15 Temperature Units F/C F
16 Security Level 0 - 3 0

17

18

NC — Normally Closed
NO — Normally Open

*Accessed and configured through the Set Clock button.

Reversing Valve

Pola rity

Forced Minimum

Temperature Difference

Reset Service

Filter Icon

Service Filter

Run Time

Maximum Allowable

Heat Set Point

Minimum Allowable

Cooling Set Point

LEGEND

12:00 AM -

11:59 PM

Sunday through

Saturday

O/B O

0-6F 2F

——

0-1950 hrs 500 hrs

35 - 99 F 80 F

35 - 99 F 65 F

12:00 AM

Monday

3

1204

HEAT PUMP CONFIGURATION (Steps 3 and 4) — To set
the thermostat for heat pump operation, Advanced Setup
Step 3 must be configured to ON. Use the UP and DOWN AR­ROW buttons to configure the step. The default is OFF. Press
the mode button to continue to Step 4. Step 4 is used to set the
reversing valve polarity for the heat pump. The variable can be
set to either “B”or “O.” Set the reversing valve polarity to the
correct value depending on the application. The default is “O.”

NOTE:Step4willappearonlyifStep3issettoON.Step5
will appear only if Step 3 is set to OFF.

→

ELECTRIC HEAT CONFIGURATION (Step 5) — Step 5 is
used to configure the thermostat for first stage electric heat. The
variable can be configured ON or OFF. The default is OFF.

NOTE:Step5willappearonlyifStep3issettoOFF.
DEADBAND (Step 6) — The deadband is the difference in

temperature above the cooling set point or below the heating
set point that the thermostat will wait before turning on the first
stage of heating or cooling. For example, if the cooling set
point is 82 F (28 C) and the deadband is 2 degrees, the first
stage of cooling will not be energized until the temperature
reaches 84 F (30 C). The range of values is 1 to 6 degrees. The
default is 2 degrees.

SET POINT MINIMUM DIFFERENCE (Step 7) — The min­imum difference between heating and cooling set points can be
user-configured. The range is from 0 to 6 degrees. The default
is 2 degrees. The minimum difference is enforced during
Autochangeover and Program On operation.

CYCLES PER HOUR LIMIT (Step 8) — The number of
times that heating or cooling can be energized per hour can be
configured. Set the variable to “d” for no limit. Set the variable
to “d1” to disable the 5-minute compressor lockout. The vari­able can also be set from 2 to 6 cycles per hour. The default is
6 cycles per hour.

Damage to compressor could result if 5-minute compressor
lockout is disabled or compressor is allowed unlimited
cycles. Do not set thermostat Advanced Setup Step 8 to “d”
or “dl” unless specifically recommended for the application.

PRE-OCCUPANCY PURGE TIMER (Step 9) — The pre­occupancy purge allows fresh outside air to be brought into the
space before the Occupied 1 time period. The timer limits the
amount of time that the purge can operate. The timer can be set
from 0 to 3 hours with 15-minute intervals. The default is
0 hours (disabled).

BACKLIGHT DISPLAY (Step 10) — The display backlight
can be set to ON (always on) or OFF (turn off 8 seconds after
usage). The default is ON.

ECONOMIZER OUTPUT (Step 11) — The thermostat has
an output terminal which can be controlled during Occupied
periods. This output terminal allows for the control of other de­vices such as economizers, lighting, water heaters, and base­board heaters. The output can be set to NO (normally open) or
NC (normally closed). The default is NO.

If the Economizer Output configuration is set to NO, then
the W3/ECO terminal of the thermostat is energized when the
thermostat is in Occupied periods 1, 2 and 3, and also during
Pre-Occupancy Purge. The W3/ECO terminal is deenergized
during Unoccupied periods.

If the Economizer Output configuration is set to NC, then
the W3/ECO terminal of the thermostat is deenergized when
the thermostat is in Occupied periods 1, 2, and 3, and also dur­ing Pre-Occupancy Purge. The W3/ECO terminal is energized
during Unoccupied periods.

SERVICE FILTER (Steps 12 and 13) — Step 12 allows the
user to reset the Service Filter counter to zero and remove the

“SERVICE FILTER” icon (if displayed on the thermostat
screen). Press the FAN button while in Setup Step 12 and the
counter is reset to zero. Press the Mode button to adjust the
number of hours the blower will run before the “SERVICE
FILTER” icon is displayed. The range is 0 to 1950 hours. Set
the variable to 0 to disable this function. The default is
500 hours.

SOFT START (Step 14) — The soft start is used when multi­ple units are used in an application. The soft start staggers the
start up times of the units in the event of power loss and restart.
Each unit should be assigned a unit ID number. The 30-second
delay time is multiplied by the unit ID number to get the total
soft start delay time for each unit. For example, if the unit ID
number is 10, set the Soft Start function to 10, the start up delay
time is 30 seconds x 10 = 300 seconds (5 minutes). The range
is 0 to 99 (ID numbers). A value of 0 disables the function. The
default is 0 (ID number).

FAHRENHEIT/CELSIUS OPERATION (Step 15) — The
thermostat can be set to operate in Fahrenheit or Celsius
degrees. Set the variable to “F” for Fahrenheit operation. Set
the variable to “C” for Celsius operation.

SECURITY LEVEL (Steps 16 to 18) — The Security Level
limits the actions that the user can perform at the thermostat.
There are 4 security levels. When the security level is set to
“0,” no security will be in effect. When the security level is set
to “1,” the set point range is limited by the settings of Steps 17
and 18. When the security level is set to “2,” the set point range
is limited by the settings of Steps 17 and 18 and the Program
On thermostat operation mode is always in effect. When the
security level is set to “3,” the set point range is limited by the
settings of Steps 17 and 18, the Program On mode is always in
effect, and set point changes are prohibited. The default is 0.

NOTE: The Fan button is ignored when security Levels 2 or 3
are in effect.

Security Maximum Heat Set Point (Step 17)

—IftheSecu­rity Level is not set to 0, the maximum heating set point will be
in effect. The user will not be allowed to set the heating set
point over the specified value. The range of values is 35 to 99 F
(1 to 37 C). The default is 80 F (27 C).

Security Minimum Cool Set Point (Step 18)

—IftheSecu­rity Level is not set to 0, the minimum cooling set point will be
in effect. The user will not be allowed to set the cooling set
point below the specified value. The range of values is 35 to
99 F (1 to 37 C). The default is 65 F (18 C).

→

Install Accessories — The following accessories can

be used with this thermostat:

• remote temperature sensor with override

(33CSSEN-WB)

• remote temperature sensor (33CSSEN-01)

• Add-a-Wire™ accessory (33CSACC-AW)

• duct temperature sensor (33CSSEN-DS)

• Add-a-Subzone™ accessory (33CSACC-AZ)

• wireless remote sensor (33CSRFS-RC/RE)

Refer to the accessory installation instructions for each

accessory for more information.
REMOTE TEMPERATURE SENSOR — A remote temper-

ature sensor may be provided to read the temperature from a
space. If a remote temperature sensor is connected, the thermo­stat will ignore the reading of its internal sensor. When the ther­mostat is using a reading from a remote sensor, the degree sym­bol above the temperature reading will blink.

When installing a remote sensor, do not run the wires in the
same conduit as the HVAC equipment control wires, fire alarm
wiring, or other high voltage wiring. Do not use building
metalwork as a ground. Use only unshielded wire.

NOTE: Sensors can only be averaged when using a wireless
remote sensor (33CSRFS-RC/RE).

1204

4

Program Thermostat Schedules — Before program-

ming the thermostat, plan the thermostat daily schedule. The
schedule is divided into 7 days (Monday through Sunday).
Each day has from 2 to 4 time periods (Occupied 1, Occu­pied 2, Occupied 3, Unoccupied) depending on the configura­tion of the thermostat. Each occupied time period has a start
time, stop time, heating set point, and cooling set point. The un­occupied time period has a heating set point and a cooling set
point. The unoccupied time period is active whenever an occu­pied time period is not active. Fill in Table 3 as an aid to pro­gramming the daily schedules.

PROGRAMMING MODE — To program the daily sched­ules, perform the following procedure:

1. Enter programming mode by pressing the Program but­ton. The Occupied 1 annunciator will appear on the ther­mostat display. Use the UP ARROW and DOWN AR­ROW buttons to set the maximum number of Occupied
periods for each day. The thermostat can be set to 1, 2,
or 3. After the number of Occupied periods has been
selected, press the Mode button. See Fig. 5.

2. The cooling set point for Occupied 1 will be displayed.
Use the UP ARROW and DOWN ARROW buttons to
raise or lower the cooling set point until the desired tem­perature is shown. The range of acceptable values is 35 to
99 F (1 to 37 C). Press the Mode button to continue. See
Fig. 5.

3. The heating set point for Occupied 1 will be displayed.
Use the UP ARROW and DOWN ARROW buttons to
raise or lower the heating set point until the desired tem­perature is shown. The range of acceptable values is 35 to
99 F (1 to 37 C). Press the Mode button to continue. See
Fig. 5.

4. The cooling set point for Unoccupied will be displayed.
Use the UP ARROW and DOWN ARROW buttons to
raise or lower the cooling set point until the desired tem­perature is shown. The range of acceptable values is 35 to
99 F (1 to 37 C) or “OF”(no unoccupied cooling). Press
the Mode button to continue.

5. The heating set point for Unoccupied will be displayed.
Use the UP ARROW and DOWN ARROW buttons to
raise or lower the heating set point until the desired tem­perature is shown. The range of acceptable values is 35 to
99 F (1 to 37 C) or “OF” (no unoccupied heating). Press
the Mode button to continue.

6. The day of the week will be shown. Use the UP ARROW
and DOWN ARROW buttons to change the day of the
week until the desired starting day is shown. Possible
choices are M (Monday) through S (Sunday). Press the
Mode button when the desired day is shown.

7. The Start Time for Occupied 1 will be displayed. Use the
UP ARROW and DOWN ARROW buttons to raise or
lower the time until the desired Start Time is shown. Press
the Mode button to continue. See Fig. 6.

8. The Stop Time for Occupied 1 will be displayed. Use the
UP ARROW and DOWN ARROW buttons to raise or
lower the time until the desired Stop Time is shown. Press
the Mode button to continue.

9. The On/Off icon will be displayed. Use the UP ARROW
to turn the Occupied 1 period ON for this day. Use the
DOWN ARROW to turn the Occupied 1 period OFF for
this day.

→

10. If more than one occupied period has been selected in
Step 1, repeat Steps 2 through 9 to program the remaining
schedule for Occupied periods 2 and 3.

→

11. The Copy command can be used to copy the previous
day’s schedule if the schedules are the same. The copy
command becomes available after all the occupied peri­ods are programmed in a day. Use the UP ARROW to
change the copy command to YES. Use the DOWN­ARROW to change the copy command to NO. Press the
Mode button when the choice has been made. See Fig. 7.

If NO was selected, the schedule will automatically
change to the next day and the user must enter the occu­pied schedules for that day.

NOTE: Occupied 1 schedule heating and cooling set
points are the same for each day. Occupied 2 and 3 set
points may be set to different values for each day of the
week.

If YES was selected, the schedule will be copied to the
next day. The schedule copy may be repeated until Sun­day is reached. The Sunday schedule cannot be copied to
Monday.

12. After all the times and set points for each day have been
entered, press the Program button to exit programming
mode.

NOTE: The thermostat will continue to follow the schedule
until a new one is entered.

Fig. 5 — Setting Occupied 1 Set Points

Fig. 6 — Start Time Display

Fig. 7 — Copy Command Display

5

1204

If only one occupied schedule is selected, the Occupied 2
and 3 schedules are skipped. If the start time is set later in the
day than the stop time, the program will run from midnight of
that day to the stop time and then from the start time to mid­night. If the same start and stop times are programmed for an
occupancy schedule, the thermostat will be in Occupied mode
for 24 hours. If one occupied period starts or stops within an­other occupied period, the lower numbered schedule has priori­ty. For example, if schedule Occupied 3 is running for 24 hours
and Occupied 2 schedule comes on from 1 to 3 PM, the set
points from Occupied 2 are in effect from 1 to 3 PM.

OVERRIDING THE SCHEDULE — The schedule can be
overridden by pressing the UP or DOWN ARROW buttons to
change the desired temperature. The thermostat will use the
new set point until the next scheduled time period starts.

Calibrate Sensor — Every thermostat is factory cali-

brated. Under normal circumstances there will never be a need
to re-calibrate the thermostat. If re-calibration must be done,
perform the following procedure:

1. Hold down the Mode and Fan buttons for 5 seconds. All
of the icons on the display screen will appear. Release the
buttons. Press the UP and DOWN ARROW buttons
simultaneously.

2. Press the UP and DOWN ARROW buttons simulta­neously again. The current temperature will be displayed.

3. Use an accurate thermometer to measure room tempera­ture. Press the UP or DOWN ARROW buttons until the
flashing number equals room temperature.

4. Press the Mode button to return to normal operation.

Check Thermostat Operation — To check thermo-

stat operation, perform the following procedure:

1. Press the Mode button repeatedly until the Heat icon ap­pears on the display. The thermostat is now in Heating
mode.

2. Press the Fan button. The Fan Auto icon will appear on
the display screen. Press the UP ARROW button until the
heating set point is 10 F (6 C) higher than the current
room temperature. Heating and fan should be energized.

3. Press the Mode button repeatedly until the Cool icon ap­pears on the display. The thermostat is now in Cooling
mode.

4. Press the DOWN ARROW button until the cooling set
point is 10 F lower than the current room temperature.
Cooling and fan should be energized.

5. Press the Mode button repeatedly until the Off icon ap­pears. Press the Fan button until the display reads Fan On.
The fan should energize.

6. If heating, cooling, or fan operation do not energize,
check wiring and consult Table 4.

Table 3 — Daily Schedule Planner

Final Checklist

1. Put away tools and instruments. Clean up debris and
packaging.

2. Review Owner’s Guide with occupant or owner.

3. Leave the manuals with owner.

OPERATION

The Mode button selects the operating mode of the thermo­stat. If OFF is selected, the thermostat will not enter Heating or
Cooling mode. If HEAT is selected, the thermostat will only
enter Heating mode (if the room temperature is below the heat­ing set point). If COOL is selected, the thermostat will only en­ter Cooling mode (if the room temperature is above the cooling
set point). If AUTO is selected, the thermostat will enter Heat­ing or Cooling mode based on the room temperature and the
heating and cooling set points. If PROGRAM ON is selected,
the stored schedule is enabled and the thermostat will follow
the Occupied and Unoccupied schedules stored in its memory.

Auto-Changeover — When the thermostat mode is set

to AUTO, the thermostat will provide automatic changeover
from Heating to Cooling mode and Cooling to Heating mode
when required. The thermostat will automatically switch to
maintain the desired temperature setting. The thermostat does
not need to be manually changed from heating to cooling or
cooling to heating operation.

Two-Stage Operation — The second stage of heat or

cool is turned on when the first stage has been on for a mini­mum of 2 minutes and the temperature differential from the set
point is equal to or greater than the set point plus the deadband
plus 2 degrees.

Clock Backup — In the event of a power loss, the ther-

mostat will keep time for a minimum of 48 hours without ex­ternal power or batteries.

→

Fan Operation — If Fan On is selected, the fan will run

continuously during occupied schedule (except when Mode is
switched to OFF). The fan will be off during unoccupied
schedule except during heating or cooling operation.

If Fan On is not selected, the fan will only operate during
heating or cooling operation.

NOTE: The Fan button will be ignored when security levels 2
or 3 are in effect.

Emergency Heat — Emergency heat is available for

heat pump applications. To turn on emergency heat, press and
hold the Fan button. While holding the Fan button, press the
UP button for 2 seconds. An ‘‘EH’’ will be displayed. During
emergency heat, the fan will operate and the second stage of
heat will be energized (locking out the first stage compressor).
To exit emergency heat, press and hold the Fan button. While
holding the Fan button, press the UP button for 2 seconds. Dur­ing emergency heat, only OFF and HEAT modes are available.

DAY

OF THE

WEEK

Monday /// /// /// /

Tuesday /// /// /// /

Wednesday /// /// /// /

Thursday /// /// /// /

Friday /// /// /// /

Saturday /// /// /// /

Sunday /// /// /// /

NOTE: The cooling temperature set point must be higher than the heating temperature set point.
(The temperature difference may be changed in the advanced set up configuration.)

Occupied 1 Occupied 2 Occupied 3 Unoccupied

Start / Stop / Heat / Cool Start / Stop / Heat / Cool Start / Stop / Heat / Cool Heat / Cool

1101

SCHEDULE

6

Electric Heat — When the Electric Heat option in the ad-

vanced set up is set to ON (configured by installer), the thermo­stat will turn on the fan immediately any time there is a heat
demand. This feature should only be used on first stage electric
heating applications. Do not use with gas heat.

Holiday Mode — When the thermostat is in Holiday

mode, the thermostat will operate under Unoccupied set points.
To configure and activate the Holiday mode, press the Holiday
button. The ‘‘HOL’’ icon will be displayed along with the re­maining days of Holiday mode operation. Press the UP or
DOWN ARROWS to select the number of days that the holi­day schedule will be in effect. A value of 0 disables Holiday
mode. The duration can be set from 1 to 99 days. The thermo­stat will enter Holiday mode on midnight of the next day after
the mode has been activated. Holiday mode will remain in
effect until midnight of the last configured day.

→

If the Holiday mode is in effect, the number of days remain­ing and the “HOL’’ icon will be displayed. The Override button
will be active during Holiday mode. The Dry Contact Switch is
ignored.

To turn off the Holiday mode before the remaining config­ured days have passed, press the Holiday button to enter into
the configuration mode. Press the DOWN ARROW to set the
number of days to zero. Holiday mode will be disabled.

Remote Temperature Sensor — A remote tempera-

ture sensor is available to read the temperature from a space. If
a remote temperature sensor is connected, the thermostat will
ignore the reading of its internal sensor. When the thermostat is
using a reading from a remote sensor, the degree symbol above
the temperature reading will blink.

Keypad Lock — To prevent unauthorized use of the ther-

mostat, the front panel buttons can be disabled. To disable or
lock the keypad, press and hold the Mode button. While hold­ing down the Mode button, press the UP and DOWN ARROW
buttons simultaneously. The ‘‘Locked’’ icon will appear on the
display.

The thermostat is unlocked by performing the same proce­dure. Press and hold the Mode button. While holding down the
Mode button, press the UP and DOWN ARROW buttons
simultaneously. The ‘‘Locked’’ icon will be removed from the
display.

→

Dry Contact Switch/External Control — A dry con-

tact switch is provided to allow an external device to force the
thermostat into Occupied 1 mode. When the thermostat is
forced into Occupied 1 mode via the dry contact closure, the
Occupied 1 icon will blink each second. The external device is
wired to contacts CK1 and CK2. See Fig. 8.

NOTE: Twenty-four volt power is not required for CK1 and
CK2.

When using the auxiliary input or controlling multiple
HVAC units with a single thermostat, it is possible to encounter
transformer phasing problems that will interfere with thermo­stat operation.

Connecting transformers that are not phased correctly may
result in a direct short, which could damage transformers and/
or the thermostat. Phasing problems are likely if the units share
a common ground with secondary grounded transformers.

Determining proper phasing can be difficult without the
help of an electrician (especially across different building
transformers). Damage to equipment can result if phasing
is improperly done. The use of isolation relays is recom­mended before attempting phasing.

Do not attempt to rewire equipment internally to phase
units. Damage to unit components may occur.

To avoid this problem, if possible, phase all HVAC units to­gether. If phasing is impractical, isolation relays may be used to
isolate the transformers. To isolate the auxiliary input, use a
separate transformer for the auxiliary control device (usually a
timeclock). Connect the device to an isolation relay coil. Con­nect one set of isolated contacts to each thermostat at CK1 and
CK2.

To prevent phasing problems when controlling multiple
HVAC units with one thermostat, phase the HVAC units or use
isolation relays to isolate the unit transformers. One unit will be
connected directly to the thermostat and the unit will power the
thermostat. All other units will require one set of isolated con­tacts for each of the following: Heat, Cool, Fan, and Reversing
Valve (if required).

Units that are phased will have the high voltage legs to the
24 VAC power transformer in common. This requires identify­ing which terminals from the high voltage input lugs are pro­viding power to the transformer. Do not assume that the same
terminals will always provide power to the transformer. For
each unit, check the unit wiring diagram. See Fig. 9.

SOFT START — When multiple thermostats are controlled
by the same external device, a Soft Start option can be used to
stagger the turn on times of the HVAC equipment. This feature
may cause a delay in operation after entering Unoccupied
mode.

10-Watt Resistor — A 10-watt, 270-ohm resistor is pro-

vided with the thermostat. This resistor should only be used in
applications where it is necessary to use 4 wires in a power­stealing mode when the common wire (C) is not available. It is
recommended that a common wire be used whenever possible.
Refer to the Troubleshooting section for more information on
resistor use and wiring.

7

1204

110 VA C

TIMECLOCK

ISOLATION

RELAY

COIL

TRANSFORMER

NOTE: Additional relays may be used. Relay coils must be connected in parallel.

→

Fig. 8 — Typical Dry Contact Switch Wiring

CK1

THERMOSTAT

CK2

CK1

THERMOSTAT

CK2

CK1

THERMOSTAT

CK2

A

SITE

POWER

B

C

→

1101

L

1

L

L

3

2

24 VAC

UNIT WITH

TRANSFORMER

ON L AND L

2

3

Fig. 9 — Example of Unit Phasing

8

L

L

1

2

24 VAC

UNIT WITH

TRANSFORMER

ON L AND L

1

L

3

2

TROUBLESHOOTING

→

Table 4 — Thermostat Troubleshooting

PROBLEM SOLUTION

Display on thermostat not illuminated. Check for 24 vac at the R terminal connection. Terminal R must be

‘‘Service Filter’’ is displayed on thermostat. After the configured number of blower operating hours, the Service Filter

Cooling will not energize. Select COOL mode. Decrease cooling set point to 10 degrees below room

Heating will not energize. Select HEAT mode. Increase heating set point to 10 degrees above room

When using 4 wires (R,G,W,Y), the cooling equipment
tries repeatedly to turn on, but cannot. At times the
display dims or disappears.

When using 4 wires (R,G,W,Y), the heating equipment
tries repeatedly to turn on, but cannot. At times the
display dims or disappears.

When controlling a heat pump, heat comes on during
cooling cycle.

When calling for cooling, both heating and cooling are
energized.

When controlling a commercial heat pump unit, unit
runsinreverseorheatingisalwayson.

The thermostat temperature display rises to 99 F. There is not enough voltage to the thermostat. Check wiring and power

The resistor labeled “L3” on the thermostat is burned
out and brown. Thermostat will not work.

connected for proper thermostat operation.

message will be displayed. This reminds the owner to replace the filter.
Reset the Service Filter feature to reset the blower operation timer to 0
hours.

temperature. Check for 24 vac at Y1 terminal with a load connected. If
present, thermostat is operating correctly and problem is with wiring or
equipment. If 24 vac is not present, replace the thermostat. Check for Com­pressor Cycle per Hour Limit. Cooling may be locked out.

temperature. Check for 24 vac at W1/O/B terminal with a load connected. If
present, thermostat is operating correctly and problem is with wiring or
equipment. If 24 vac is not present, replace the thermostat.

There is not enough power available. Connect a 270 ohm, 10 watt power
resistor at the air-conditioning equipment between terminals W and C
(non-heat pump applications only).

There is not enough power available. Connect a 270 ohm, 10 watt power
resistor at the air-conditioning equipment between terminals Y and C
(non-heat pump applications only).

Configure thermostat for heat pump operation (Table 2, Step 3).

The thermostat is configured for a heat pump. Configure the thermostat for
non-heat pump operation (Table 2, Step 3).

Commercial heat pumps require that Heat Pump Option on thermostat is
turned OFF.

supply.
The thermostat has been wired incorrectly and the circuit board is burned

out. Thermostat must be replaced.

9

1204

Copyright 1997 Carrier Corporation

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 1 4
Ta b 1 a 1 3a

PC 111 Catalog No. 533-317 Printed in U.S.A. Form 33CS-12SI Pg 12 1204 12-97 Replaces: New