Carrier 33CS User manual

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111 Catalog No. 533-30019 Printed in U.S.A. Form 33CS-55SI Pg 1 11-04 Replaces: 33CS-51SI
Book 1 4
Tab 11a 13a
Installation and Operating Instructions
Part Number 33CSSN2-FC
CONTENTS
SAFETY CONSIDERATIONS ......................1
GENERAL ........................................ 1
INSTALLATION ................................. 1-8
Select Thermostat Location ...................... 1
Install Thermostat................................1
Changeover Sensor ..............................5
Configure Advanced Setup....................... 5
Factory Defaults ................................. 6
Calibrate Sensor ................................. 6
Check Thermostat Operation.....................6
Final Checklist ...................................8
OPERATION.................................... 8,9
Select Desired Temperature ...................... 8
Four-Pipe Operation..............................8
Two-Pipe Operation ..............................8
Fan Operation .................................... 8
Keypad Lock .....................................8
Minimum Heat/Cool Temperature Difference ..... 8
Single Set Point Operation .......................8
Dual Set Point Operation .........................9
Outside Air Temperature Sensor .................9
Locking Cover ...................................9
Dry Contact Switch/External Control .............9
TROUBLESHOOTING.............................9
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 sym-
bol . When the safety alert symbol is present on equipment
or in the instruction manual, be alert to the potential for person-
al 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 fan coil non-programmable thermostats are wall-
mounted or unit-mounted, low-voltage thermostats that main-
tain room temperature by controlling the operation of a fan coil
unit. Separate heating and cooling set points, auto-changeover
capability, 2-pipe or 4-pipe configurability, and single or dual
set point options allow for greater flexibility.
The thermostats are normally wall-mounted for 42C and
42D fan coil units. For 42S and 42V fan coil units, the thermo-
stat is mounted on the fan coil unit or inside the fan coil unit on
a junction box. For 42S and 42V fan coil units, the thermostat
may also be remote wall-mounted, if desired.
Batteries are not required. During power interruption the
internal NEVERLOST™ memory stores configuration settings
for an unlimited amount of time.
The thermostat can be configured to accept several different
equipment configurations, including 2-pipe or 4-pipe operation.
The temperature display range of the thermostat is 35 to
99F(2to36C).
INSTALLATION
Select Thermostat Location — The thermostat should
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 32 to
122F(0°to50C)
• 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)
Install Thermostat
1. Turn off all power to fan coil unit.
IMPORTANT: Read entire instructions before starting the
installation.
IMPORTANT: The thermostat is factory-configured for
use in 4-pipe applications. The advanced setup must be
performed to configure the thermostat for use with 2-pipe
applications.
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.
33CS
Fan Coil
Non-Programmable Thermostat

2
2. If an existing thermostat is being replaced:
a. Remove existing thermostat from the wall or unit.
b. Disconnect wires from existing thermostat. Do not
allow wires to fall back into the wall or unit. 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. Thermostat can be mounted directly to the wall or onto
the unit when required. See Fig. 1. A wall mounting plate
is provided when an existing hole in the wall is too large
for the thermostat or when mounting to a junction box
(the thermostat will not completely cover a 2 x 4-in.
junction box).
4. If mounting plate is being used, install mounting plate on
wall or junction box. Mounting plate consists of two
pieces: the metal mounting plate (see Fig. 2A) and
the plastic mounting plate (see Fig. 2B). The standard
mounting plate will cover a 2 x 4-in. or 4 x 4-in. junction
box. Accessory mounting plates of different sizes are
also available. Accessory mounting plate part numbers
are P474-0421 (7 x 4 1/4-in.) or P474-0421L (5 1/2x
61/4-in.).
a. Install the metal mounting plate to wall or junction
box with 2 screws provided. Use the outermost
screw holes.
b. Place plastic mounting plate over the metal mount-
ing plate. Be sure wiring exits through holes in
both mounting plates. Plastic mounting plate is
secured to metal mounting plate when the thermo-
stat mounting base is installed (Step 7).
5. Remove the thermostat cover from back plate by
grasping the top and bottom of the cover and squeezing
together while pulling apart to expose mounting holes
and wiring connections. See Fig. 1.
6. Route thermostat wires through large hole in thermostat
mounting base. Remove outer sheath from wires for add-
ed flexibility. Standard solid or multi-conductor thermo-
stat 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. If accessory mounting plate is not used:
Level back plate against wall and mark wall through the
2 mounting holes in base. Drill two 3/16-in. mounting
holes in wall where marked. Mounting holes are provided
if installing on unit.
Secure back plate to wall or unit with 2 screws and
anchors provided. Ensure all wires exit through hole in
back plate.
If accessory mounting plate is used:
Secure the metal mounting plate in the wall with two
screws provided. Use the outermost screw holes. Place
plastic mounting plate and thermostat back plate over
the metal mounting plate. Secure mounting plates and
thermostat back plate to the wall with 2 screws provided.
The thermostat mounting base should fit securely in the
indentation provided in the plastic mounting plate. 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. 3-7 and Tables 1 and 2.
9. Push excess wiring into wall. Seal hole in wall to prevent
drafts.
10. Re-attach thermostat cover to back plate.
11. Turn on power to unit. The thermostat will receive power
from the fan coil unit.
Be careful not to drill into wiring in wall. Electrical shock
could result.
Improper wiring or installation may cause damage to the
thermostat. Check to ensure wiring is correct before pro-
ceeding with installation of unit. Do not run thermostat
wiring in same conduit as high-voltage power, or HVAC
wiring. Interference from other wiring may cause incorrect
readings or commands from thermostat.
IMPORTANT: The thermostat is strictly a low-voltage
control. One or two 33ZCRLYBRD relay boards must
be installed to isolate any line voltage from the fan coil
low voltage controls.
WIRING
TERMINAL
BLOCK
HOLE FOR
WIRING
MOUNTING
HOLE
MOUNTING
HOLE
C
Y1 G3
GR W1G2
3 1/8"
3 1/8" 1"
CK1
H2O
RS+5 RS
LEVEL LEVEL
3 9/16"
3 3/4"
Fig. 1 — Thermostat Back Plate Mounting
and Wiring
Fig. 2A — Metal Mounting Plate Dimensions

3
COM
G3/(Y)
G2/(W)
G
LO
MED
HI
(HEAT)
(COOL)
(VALVE)
FAN
COM
G3/(Y)
G2/(W)
G
LO
MED
HI
(HEAT)
(COOL)
(VALVE)
FAN
24vac
R
C
COM
COM
G
G
G3(Y)
G3(Y)
G2(W)
G2(W)
VALVE
FAN
R
C
G2
W1
G3
Y1
G
33ZCRLYBRD
THERMOSTAT
COM
G3/(Y)
G2/(W)
G
LO
MED
HI
(HEAT)
(COOL)
(VALVE)
FAN
24vac
R
C
COM
G
G3(Y)
G2(W)
RS+5
RS GND
RS
REMOTE SENSOR
DRY CONTACT
33CSSEN-01
33CSSEN-WB
33CSSEN-DS
33ZCRLYBRD
RC
R
C
G2
G3
G
RS+5
RS
H2O
Ck1
THERMOSTAT
Y1
W1 HC
24 Volt Water
Valves
Fig. 4 — Typical Wiring Diagram — 4-Pipe, Low Voltage Valves,
Remote Temperature Sensor, and Dry Contact Switch
4 1/4”
4 1/4”
3 1/8”
3 1/8”
Fig. 2B — Plastic Mounting Plate Dimensions
Fig. 3 — Typical Wiring Diagram — 4-Pipe,
2-Relay Boards, Line Voltage Water Valves

4
COM
G3/(Y)
G2/(W)
G
LO
MED
HI
(HEAT)
(COOL)
(VALVE)
FAN
24vac
R
C
COM
G
G3(Y)
G2(W)
R
C
G2
W1
G3
G
V
24 Volt Water
Valve
Y1
33ZCRLYBRD
THERMOSTAT
COM
G3/(Y)
G2/(W)
G
LO
MED
HI
(HEAT)
(COOL)
(VALVE)
FAN
24vac
R
C
COM
G
G3(Y)
G2(W)
RS+5
RS GND
RS
REMOTE SENSOR
H2O
Changeover Sensor
33CSWCO-FC
33CSSEN-01
33CSSEN-WB
33CSSEN-DS
33ZCRLYBRD
RC
R
C
G2
G3
G
RS+5
RS
H2O
THERMOSTAT
V
24 Volt Water
Valve
Y1
Fig. 5 — Typical Wiring Diagram — 2-Pipe, Low Voltage Valve, Heat Only or Cool Only
Fig. 6 — Typical Wiring Diagram — 2-Pipe, Low Voltage Valve, Water Changeover Sensor

5
Table 1 — Thermostat Wiring Terminations
(4-Pipe Systems)
Table 2 — Thermostat Wiring Terminations
(2-Pipe Systems)
Changeover Sensor — If the thermostat is being used
with a two-pipe heating/cooling system, a changeover sensor
(33CSWCO-FC) may be used to provide automatic heat/cool
mode changeover.
Configure Advanced Setup — To enter the advanced
setup screens of the thermostat, press the Mode and Fan buttons
simultaneously for 10 seconds. The display will change. 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. Use the UP and DOWN ARROW buttons to change
the settings. There are 13 Advanced Setup Steps. See Table 3.
Press the Mode and Fan buttons at the same time to exit the Ad-
vanced Setup mode.
DISPLAY CONFIGURATION (Step 1) — The Display con-
figuration is used to select what the thermostat will display
when it is not being used. If the configuration is set to ON, the
thermostat will display mode, fan operation, set points, and
room temperature. If the configuration is set to OFF, the ther-
mostat will be blank. If any button is pressed, the thermostat
screen will return to full display. The default is ON.
SINGLE OR DUAL SET POINT CONFIGURATION (Step
2) — Step 2 is used to configure the thermostat for single or
dual set point operation. The configuration can be set to 1 or 2.
The default is 2. When the configuration is set to 1, there is
only one set point used for both heating and cooling. When
the configuration is set to 2, there are two set points (one for
heating, one for cooling).
TWO OR FOUR PIPE SYSTEM CONFIGURATION
(Step 3) — Step 3 is used to configure the thermostat for use in
a 2-pipe or 4-pipe system. When the configuration is set to 2,
the thermostat will be configured for use with a 2-pipe system.
Advanced Setup Step 4 must be configured correctly if Step 3
is set to 2. When the configuration is set to 4, the thermostat
will be configured for use with a 4-pipe system. The default
is 4.
NOTE: Advanced Setup Step 4 will only be shown if Step 3 is
set to 2.
TWO-PIPE SYSTEM OPERATION (Step 4) — Step 4 is
used to configure the thermostat for use in a 2-pipe system.
The configuration can be set to 1, 2, 3, 4, or 5. The default is 3.
When the Two-Pipe Operation configuration is set to 1, the
two-pipe system will function as a Heat-Only system. When
the Two-Pipe Operation configuration is set to 2, the two-pipe
system will function as a Cool-Only system. When the Two-
Pipe Operation configuration is set to 3, the two-pipe system
will function as a Heat/Cool Auto-Changeover system. When
the Two-Pipe Operation configuration is set to 4, the two-pipe
system will function as a Heat/Cool system with auxiliary elec-
tric heat (lockout electric heat when hot water is available).
When the Two-Pipe Operation configuration is set to 5, the
two-pipe system will function as a Heat/Cool system with total
electric heat (no hot water heat).
EXISTING WIRE
DESIGNATION FUNCTION TERMINAL CONNECTION
Y1,Y,orC Cooling Y1
W1,W,orH Heating W1
Rh,R,M,Vr,orA Power R
CCommon C
G, F, or LOW Low Fan Speed G
MED Medium Fan Speed G2
HIGH High Fan Speed G3
EXISTING WIRE
DESIGNATION FUNCTION TERMINAL CONNECTION
Y1,Y,orC Water Valve Y1
W1,W,orH Strip Heater W1
Rh,R,M,Vr,orA Power R
CCommon C
G, F, or LOW Low Fan Speed G
MED Medium Fan Speed G2
HIGH High Fan Speed G3
COM
G3/(Y)
G2/(W)
G
LO
MED
HI
(HEAT)
(COOL)
(VALVE)
FAN
24vac
R
C
COM
G
G3(Y)
G2(W)
R
C
G2
G3
G
VVR
24 Volt Cold
Water Valve 24 Volt Relay
to Control Strip Heater
Y1
W1
33ZCRLYBRD
THERMOSTAT
Fig. 7 — Typical Wiring Diagram — 2-Pipe, Low Voltage Valve, Chilled Water with Electric Strip Heat

6
FAN OPERATION (Step 5) — If the fan operation is set to
ON, the fan will operate at continuous low speed. If the fan
operation is set to OFF, the fan will cycle off and will only be
energized during a heating or cooling cycle (AUTO mode). The
default is ON.
NOTE: When a remote temperature sensor is used, the choice
should be Fan ON.
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.
NOTE: If single set point operation is used, the deadband will
be above and below the single set point.
SET POINT MINIMUM DIFFERENCE (Step 7) — The min-
imum 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.
BACKLIGHT DISPLAY (Step 8) — The display backlight
can be set to ON (always on) or OFF (turn off 8 seconds after
usage). The default is OFF.
FAHRENHEIT/CELSIUS OPERATION (Step 9) — The ther-
mostat 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. The default is “F.”
REMOTE SENSOR (Step 10) — The Remote Sensor con-
figuration is used to configure the operation of a remote sensor
(if used). If the configuration is set to Yes, then the remote
sensor will function as an outdoor temperature sensor (read
only). The thermostat will not control to the temperature. If the
configuration is set to No, then the remote sensor will function
as a remote temperature sensor. The thermostat will control to
the temperature reading from the sensor. The default is Yes.
DRYCONTACTSWITCH(Step11)—Step11isusedto
configure the dry contact switch as normally open (NO) or
normallyclosed(NC).ThedefaultisNO.
DRY CONTACT SWITCH OPERATION (Step 12) — Step
12 is used to configure the operation of the dry contact switch.
When the dry contact switch is active, the thermostat can enter
Occupied or Unoccupied mode. If the configuration is set to
Occupied, then the thermostat will enter Occupied mode when
the dry contact switch is active. If the configuration is set to
Unoccupied, then the thermostat will enter Unoccupied mode
when the dry contact switch is active. The default is Occupied.
NOTE: Step 13 will only be displayed if Step 12 is set to
Unoccupied.
DRY CONTACT SWITCH UNOCCUPIED OPERATION
(Step 13) — If the Step 12 configuration is set to Unoccupied,
then the thermostat will enter Unoccupied mode when the dry
contact switch is energized. Step 13 determines what the ther-
mostat will do when it enters Unoccupied mode. If the configu-
ration is set to Unoccupied Set Points, then the thermostat will
control to the unoccupied set points. If the configuration is set
to Off, the thermostat will turn off the fan coil during Unoccu-
pied mode. The default is to control to the unoccupied set
points.
The dry contact switch configuration allows for the dry
contact switch input to be used for a condensate overflow
switch when correctly configured. For example, when the drain
pan is full, a condensate switch would trip the dry contact,
causing the fan coil unit to shut down.
Table 3 — Advanced Setup Configuration
Factory Defaults — If the thermostat needs to be reset to
factory default settings, perform the following procedure:
1. Set the thermostat mode to OFF.
2. Hold down the Mode button and press the DOWN
ARROW button simultaneously for 5 seconds. All of the
icons on the display screen will appear.
3. Press and hold the Fan button until Fd (factory defaults)
appears on the screen.
4. Press the Mode button twice to return to normal display.
Calibrate Sensor — Every thermostat is factory-
calibrated. 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. Set the thermostat mode to OFF.
2. Hold down the Mode and DOWN ARROW buttons for
5 seconds. All of the icons on the display screen will
appear. Release the buttons.
3. Press the Mode button. The current temperature will be
displayed.
4. Use an accurate thermometer to measure room tempera-
ture. Press the UP or DOWN ARROW buttons until the
number equals room temperature.
5. Press the Mode button to return to normal operation.
Check Thermostat Operation
FOUR-PIPE OPERATION — To check thermostat opera-
tion with a 4-pipe system, perform the following procedure:
1. Turn on power to fan coil unit.
2. Press the Mode button repeatedly until the Heat icon
appears on the display. The thermostat is now in Heating
mode.
3. Press the UP ARROW button until the heating set point is
10 F (6 C) higher than the current room temperature.
The hot water valve will open and the fan should be
energized.
STEP DESCRIPTION RANGE DEFAULT
1Display Blanking OFF/ON ON
2Single/Dual Set Point 1, 2 2
32 or 4 Pipe System 2, 4 4
42-Pipe System
Operation 1-5 3
5Fan Operation OFF/ON ON
6Deadband 1-6 degrees 2
7Set Point Minimum
Temperature Difference 0 - 6 degrees 2
8Thermoglow™
Backlight OFF/ON OFF
9Temperature Units F/C F
10 Remote Sensor Setup YES/NO YES
11 Dry Contact Switch NO/NC NO
12 Dry Contact Switch
Operation Occupied, Unoccupied Occupied
13 Dry Contact Switch
Unoccupied Operation Off, Set Points Set Points

7
4. Press the Fan button repeatedly until the Fan icon appears
with a single bar next to it. Confirm that the fan is running
at low speed. Press the Fan button again. The Fan icon
appears with two bars next to it. Confirm that the fan is
running at medium speed. Press the Fan button again.
The Fan icon appears with three bars next to it. Confirm
that the fan is running at high speed. Press the Fan button
again. The bars next to the Fan icon should disappear.
When no bars are shown, the fan will operate in the
AUTO mode. The fan speed will automatically change
based on load requirements.
5. Press the Mode button repeatedly until the Cool icon
appears on the display. The thermostat is now in Cooling
mode.
6. Press the DOWN ARROW button until the cooling set
point is 10 F (6 C) lower than the current room tempera-
ture. The cold water valve will open and the fan should be
energized.
7. Press the Mode button repeatedly until the OFF icon
appears. Both valves should be closed and the fan should
be off.
8. If heating, cooling, or fan do not operate properly, check
wiring and consult Table 4.
TWO-PIPE OPERATION WITH CHANGEOVER SEN-
SOR AND NO STRIP HEAT — To check thermostat opera-
tion of a 2-pipe system with changeover sensor, perform the
following procedure:
1. Turn on power to fan coil unit.
2. Make sure the thermostat is correctly configured for use
in two-pipe applications. Advanced Setup Step 3 should
be set to 2 (two-pipe applications). Advanced Setup Step
4 should be set to 3 (heat/cool changeover system without
electric heat).
3. Press the Fan button repeatedly until the Fan icon appears
with a single bar next to it. Confirm that the fan is running
at low speed. Press the Fan button again. The Fan icon
appears with two bars next to it. Confirm that the fan is
running at medium speed. Press the Fan button again.
The Fan icon appears with three bars next to it. Confirm
that the fan is running at high speed. Press the Fan button
again. The bars next to the Fan icon should disappear.
When no bars are shown, the fan will operate in the
AUTO mode. The fan speed will automatically change
based on load requirements.
4. If hot water heat is available, press the Mode button
repeatedly until the Heat icon appears on the display. The
thermostat is now in Heating mode.
5. Press the UP ARROW button until the heating set point is
10 F (6 C) higher than the current room temperature.
The hot water valve will open and the fan should be
energized.
6. If cold water cooling is available, press the Mode button
repeatedly until the Cool icon appears on the display. The
thermostat is now in Cooling mode.
7. Press the DOWN ARROW button until the cooling set
point is 10 F lower than the current room temperature.
The cold water valve will open and the fan should be
energized.
8. Press the Mode button repeatedly until the OFF icon
appears. The valve should be closed and the fan should
be off.
9. If heating, cooling, or fan do not operate properly, check
wiring and consult Table 4.
TWO-PIPE OPERATION WITHOUT CHANGEOVER
SENSOR — To check thermostat operation with a 2-pipe
system without changeover sensor, perform the following
procedure:
1. Turn on power to fan coil unit.
2. Make sure the thermostat is correctly configured for use
in two-pipe applications. Advanced Setup Step 3 should
be set to 2 (two-pipe applications). Advanced setup Step
4 should be set to 1 (heat only), 2 (cool only), or 5 (cool-
ing with total electric heat).
3. Press the Fan button repeatedly until the Fan icon appears
with a single bar next to it. Confirm that the fan is running
at low speed. Press the Fan button again. The Fan icon
appears with two bars next to it. Confirm that the fan is
running at medium speed. Press the Fan button again.
The Fan icon appears with three bars next to it. Confirm
that the fan is running at high speed. Press the Fan button
again. The bars next to the Fan icon should disappear.
When no bars are shown, the fan will operate in the
AUTO mode. The fan speed will automatically change
based on load requirements.
4. If heating is available, press the Mode button repeatedly
until the Heat icon appears on the display. The thermostat
is now in Heating mode. Press the UP ARROW button
until the heating set point is 10 F (6 C) higher than the
current room temperature. Heating will energize (the hot
water valve will open or the strip heat will energize) and
the fan will run.
5. If a cooling only or cooling only with strip heat system,
press the Mode button repeatedly until the Cool icon
appears on the display. The thermostat is now in Cooling
mode. Press the DOWN ARROW button until the cool-
ing set point is 10 F lower than the current room tempera-
ture. The cold water valve will open and the fan will run.
6. Press the Mode button repeatedly until the OFF icon
appears. The valve should be closed and the strip heater
and fan should be off.
7. If heating, cooling, or fan do not operate properly, check
wiring and consult Table 4.
TWO-PIPE OPERATION WITH CHANGEOVER SEN-
SOR AND STRIP HEAT — To check thermostat operation
of a 2-pipe system with changeover sensor and strip heat, per-
form the following procedure:
1. Turn on power to fan coil unit.
2. Make sure the thermostat is correctly configured for use
in two-pipe applications. Advanced Setup Step 3 should
be set to 2 (two-pipe applications). Advanced setup
Step 4 should be set to 4 (heat/cool changeover system
with auxiliary electric heat).
3. Press the Fan button repeatedly until the Fan icon appears
with a single bar next to it. Confirm that the fan is running
at low speed. Press the Fan button again. The Fan icon
appears with two bars next to it. Confirm that the fan is
running at medium speed. Press the Fan button again.
The Fan icon appears with three bars next to it. Confirm
that the fan is running at high speed. Press the Fan button
again. The bars next to the Fan icon should disappear.
When no bars are shown, the fan will operate in the
AUTO mode. The fan speed will automatically change
based on load requirements.

8
4. If hot water heat is available, press the Mode button
repeatedly until the Heat icon appears on the display. The
thermostat is now in Heating mode.
NOTE: The strip electric heat and cooling will be locked
out if hot water heat is available.
5. Press the UP ARROW button until the heating set point is
10 F (6 C) higher than the current room temperature. The
hot water valve will open or the strip heat will energize
and the fan should be energized.
6. If cold water cooling is available, press the Mode button
repeatedly until the Cool icon appears on the display. The
thermostat is now in Cooling mode.
7. Press the DOWN ARROW button until the cooling set
point is 10 F (6 C) lower than the current room tempera-
ture. The cold water valve will open and the fan should be
energized.
8. Press the UP ARROW button until the heating set point is
10 F (6 C) higher than the current room temperature.
Electric strip heating will be available if cold water is
sensed by the changeover sensor. The strip heater will
energize and the fan will run.
9. Press the Mode button repeatedly until the OFF icon
appears. The valve should be closed and the strip heat and
fan should be off.
10. If heating, cooling, or fan do not operate properly, check
wiring and consult Table 4.
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
Select Desired Temperature — The UP and DOWN
ARROW buttons are used to adjust the heating and cooling set
points. Pressing the UP and DOWN ARROW buttons in Auto
mode will adjust both the heating and cooling set points. Press-
ing the UP and DOWN ARROW buttons in either Heat or
Cool mode will adjust only the heating or cooling set point.
NOTE: If the Single Set Point mode is configured, there will
be only one set point for both heating and cooling.
Four-Pipe 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.
Two-Pipe Operation
HEAT ONLY — When the thermostat is configured for Heat
Only operation, only Heat and Off modes can be selected.
COOL ONLY — When the thermostat is configured for Cool
Only operation, only Cool and Off modes can be selected.
HEAT/COOL WITH CHANGEOVER SENSOR — When
the thermostat is configured for operation with a changeover
sensor, all modes are available for operation. If the water
temperature is changed during the year, the thermostat will
automatically lock out the incorrect mode. Heat or Cool modes
may not be available, depending on water temperature.
TOTAL OR AUXILIARY ELECTRIC HEAT — 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 room temperature is below the heating set point). For
total electric heat, a call for heat will activate the electric heater.
For auxiliary electric heat, a call for heat will either activate the
electric heater (if chilled water is in the coil), or open the coil
valve (if hot water is in the coil).
If COOL is selected, the thermostat will only enter Cooling
mode (if room temperature is above the cooling set point and
chilled water is in the coil).
If AUTO is selected, the thermostat will enter Heating or
Cooling mode based on the room temperature and the heating
and cooling set points.
Fan Operation — The Fan button is used to select fan
operation. When only the Fan icon is shown, the fan is in “Au-
to” mode and will run continuously (unless thermostat mode is
set to OFF or thermostat is in unoccupied mode and heating or
cooling are not active). The thermostat will increase or de-
crease the fan speed based on temperature demand.
Fan operation can also be set to always run at Low, Medi-
um, or High speeds. To set fan operation at Low speed, press
the Fan button until one bar is shown next to the Fan icon. The
fan will run continuously at Low speed (unless thermostat
mode is set to OFF or thermostat is in unoccupied mode and
heating or cooling are not active).
To set fan operation at Medium speed, press the Fan button
until two bars are shown next to the Fan icon. The fan will run
continuously at Medium speed (unless thermostat mode is set
to OFF or thermostat is in unoccupied mode and heating or
cooling are not active).
To set fan operation at High speed, press the Fan button
until three bars are shown next to the Fan icon. The fan will run
continuously at High speed (unless thermostat mode is set to
OFF or thermostat is in unoccupied mode and heating or cool-
ing are not active).
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 proce-
dure. 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.
Minimum Heat/Cool Temperature Differ-
ence — The heating and cooling set points will not be al-
lowed any closer to each other than the value set in Advanced
Setup Step 7. The minimum temperature difference is enforced
during Auto mode and Program On operation.
Single Set Point Operation — When the thermostat
is configured for single set point operation, the display on the
thermostat will change. Instead of displaying current room
temperature, the large number shown will be the user set point.
This set point is used for both heating and cooling.
To prevent short cycling in single set point mode, it is rec-
ommended that the deadband be set to a minimum of 2.
Press and hold the Mode button for 2 seconds to display
the room temperature. Press any button to return to the normal
display.

9
Dual Set Point Operation — When the thermostat is
configured for dual set point operation, there are separate heat
and cool set points. The adjustable set point range is 35 to 99 F
(2 to 36 C). When the thermostat is in Heat or Cool mode, the
set points can be adjusted to any temperature within the operat-
ing range.
When the thermostat is in Auto mode, the thermostat will
not allow the Cool set point to be lower than the Heat set point.
The thermostat will also use the programmed Deadband value
(Advanced Setup Step 6) to determine the minimum difference
between the Heat and Cool set points. If the Deadband is set for
6 degrees, the Cool set point cannot be set within 6 F of the
Heat set point.
When entering Auto mode from Heat or Cool modes, the
Heat and Cool set points will remain spread apart by the same
amount when the set points are adjusted. For example, if the
Cool set point is 80 F (adjusted in Cool mode) and the Heat set
point is 70 F (adjusted in Heat mode), when entering Auto
mode, both set points would be adjusted by the same amount
when the UP and DOWN arrow buttons are pressed. There-
fore, if the DOWN ARROW was pressed 5 times, the Cool set
point would be 75 F and the Heat set point would be 65 F. To
adjust the set points individually, enter the Heat or Cool modes
first.
Outside Air Temperature Sensor — Press and hold
the Fan button for 2 seconds to display outside temperature
(if optional outdoor sensor is wired to thermostat). Press any
button to return to normal operation.
Locking Cover — A locking cover with tamper-proof
screws is provided with the thermostat. The locking cover can
be used to keep the thermostat set points and configurations
from being changed. A special tool is required to remove the
cover.
Dry Contact Switch/External Control — Adry
contact switch is provided to allow an external device to force
the thermostat into the Unoccupied set points configured in
Advanced Setup Step 13. When the thermostat is forced
into Unoccupied set points via the dry contact closure, the
Unoccupied icon will blink each second. The external device is
wired to contacts CK1 and R. See Fig. 4.
NOTE: More than one thermostat is not required. All thermo-
stats wired to the external device will enter Unoccupied modes
at the same time.
TROUBLESHOOTING
Table 4 — Troubleshooting
PROBLEM SOLUTION
The fan always runs in Low speed, even with no temperature
demand. This is normal operation of the thermostat. If the fan needs to be shut off, switch mode to Off. The fan will not run in the unoccupied mode when there is
no call for heating or cooling.
The fan will not run in all three speeds or switches speeds in
improper order. Wiring between the thermostat and the relay board or between the relay board and the fan is incorrect. Check the wiring for proper connection.
Cold water valve opens for both a cool or heat demand in a
4-pipe system. Check the configuration of Advanced Setup Step 3. Configuration should be set for 4-pipe system.
Valve does not open in 2-pipe system. Wiring or configuration is incorrect. Check the configuration of Advanced
Setup Step 3. Configuration should be set for 2-pipe system. Make sure water
valve is wired to the Y1 terminal.
Thermostat displays large set point instead of room
temperature. This is the normal display when the thermostat is set to single set point instead of dual set point (Advanced Setup Step 2).
The thermostat will only allow Heat or Off modes in 2-pipe
installations, even though chilled water is available. Changeover sensor is faulty, improperly wired, or improperly installed. Confirm proper wiring of the changeover sensor. Confirm proper placement of the sen-
sor. If wiring and placement are proper, check the changeover sensor with an
ohmmeter as follows:
1. Remove power from the fan coil system.
2. Disconnect wiring between the sensor and the thermostat.
3. Place an ohmmeter between R and the wire just disconnected from the
thermostat.
4. The sensor should show continuity whenever the water temperature is con-
firmed to be at or below 65 F. If the sensor is open when the water tempera-
ture is at or below 65 F, replace the sensor.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111 Catalog No. 533-30019 Printed in U.S.A. Form 33CS-55SI Pg 12 11-04 Replaces: 33CS-51SI
Book 1 4
Tab 11a 13a
Copyright 2004 Carrier Corporation