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Field-Installed Accessories
SPACE TEMPERATURE SENSOR (T-55) — The T-55 space
temperature sensor (part no. 33ZCT55SPT) is a field-installed
accessory. The sensor is installed on a building interior wall to
measure room air temperature. The T-55 sensor also includes an
override button on the front cover to permit occupants to over-
ride the Unoccupied Schedule (if programmed). The jumper
wire in the installer’s packet must be connected between R and
W1 when using a T-55 device. See Fig. 30 and 31.
SPACE TEMPERATURE SENSOR (T-56) — The T-56 space
temperature sensor (part no. 33ZCT56SPT) is a field-installed
accessory. This sensor includes a sliding scale on the front
cover that permits an occupant to adjust the space temperature
set point remotely. The T-56 sensor also includes an override
button on the front cover to allow occupants to override the
unoccupied schedule (if programmed). The jumper wire in the
installer’s packet must be connected between R and W1 when
using a T-56 device. See Fig. 30 and 32.
SPACE TEMPERATURE SENSOR (T-58) — The T-58
space temperature sensor (part no. 33ZCT58SPT) is a field-in-
stalled accessory. The T-58 sensor communicates with the
Comfort
Link™ controller, providing space temperature, heat-
ing and cooling set points, and mode operation information.
The jumper wire in the installer’s packet must be connected
between R and W1 when using a T-58 device. See Fig. 33.
Refer to the T-58 installation instructions for information on
installing and configuring the T-58 sensor.
Each T-58 sensor must have a unique address on the CCN.
Each T-58 sensor must also be configured with the address of
the unit control it is communicating to.
SPACE TEMPERATURE SENSOR AVERAGING — See
Fig. 34 for space temperature averaging with T-55 sensors only.
If the use of one T-56 sensor is required, refer to Fig. 35.
ECONOMIZER — The economizer accessory usage de-
pends on model size. When installing this accessory, the unit
must be configured for economizer installation by setting
Configuration
→
ECON
→
EC.EN
to YES. The default settings
for the other economizer configurations should be satisfactory.
If they need to be changed, additional information about these
configuration settings can be found in the Economizer section.
POWER EXHAUST — The power exhaust accessory usage
depends on voltage. When installing this accessory, the unit
must be configured for power exhaust installation by setting
Configuration
→
ECON
→
PE.EN
to ENBL. The default set-
tings for the other power exhaust configurations should be
satisfactory. If they need to be changed, additional information
about these configurations can be found in the Power Exhaust
section.
TWO-POSITION DAMPER — This accessory wires direct-
ly into the low voltage circuit for the indoor fan control. No
other control configuration is needed.
INDOOR AIR QUALITY — The indoor air quality (IAQ)
sensor is a field-installed accessory which measures CO
2
levels in
the air. When installing this sensor, the unit must be configured for
IAQ use by setting
Configuration
→
AIR.Q
→
IA.CF
to a value
of 1, 2, or 3. See the Indoor Air Quality section for more
information.
OUTDOOR AIR QUALITY — The outdoor air quality
(OAQ) sensor (part no. 33ZCSENCO2) is a field-installed acces-
sory that measures CO
2
levels in the air. When installing this
sensor, the unit must be configured for OAQ use by setting
Configuration
→
AIR.Q
→
OA.CF
to a value of 1 or 2. See the
Indoor Air Quality section for more information.
SMOKE DETECTORS — The smoke detectors are field-
installed accessories. These detectors can detect smoke in
either the return air (part no. CRSMKDET001D00) or supply
and return air (part no. CRSMKSUP001B00). When installing
either detector, the unit must be configured for fire shutdown by
setting
Configuration
→
UNIT
→
FS.SW
to normally open (1)
or normally closed (2).
NOTE: When a Humidi-Mizer™ system is installed, the
inputs to the fire shutdown are moved to the control harness.
See the Third Party Control section on page 38 for more
information.
FILTER STATUS — The filter status accessory (part no.
CRSTATUS003B00) is a field-installed accessory. This accesso-
ry detects plugged filters. When installing this accessory, the unit
must be configured for filter status by setting
Configuration
→
UNIT
→
FL.SW
to normally open (1) or normally closed (2).
Normally open (1) is the preferred configuration.
FAN
STATUS
—
The fan status accessory (part no.
CRSTATUS003B00) is a field-installed accessory. This acces-
sory detects when the indoor fan is blowing air. When installing
this accessory, the unit must be configured for fan status by
setting
Configuration
→
UNIT
→
FN.SW
to normally open (1)
or normally closed (2). Normally open (1) is the preferred
configuration.
ENTHALPY SENSORS — The enthalpy accessories (part
no. CRENTSNG02A00 and CRENTDIF02A00) are field-
installed accessories. The first accessory (outdoor air only)
determines when the enthalpy is low relative to a fixed refer-
ence. Adding the second accessory (return air) compares the
enthalpy between the outdoor and return airstreams. In each
case, the enthalpy 4 to 20 mA signals are converted to a switch
output which is read by the ECB. When installing this accesso-
ry, the unit must be configured for enthalpy-based control by
setting
Configuration
→
ECON
→
EN.SW
to normally open (1).
See Fig. 14-19 for wiring details.
RETURN/SUPPLY AIR TEMPERATURE SENSOR — The
temperature sensor (part no. 33ZCSENSAT) is a field-installed
accessory which may be installed on the common return air
duct and/or the common supply air duct near the unit. The duct
return air temperature (RAT) may be selected for display only
if the space temperature offset (SPTO) is not used. When in-
stalling the sensor, the unit must be configured by setting
Configuration
→
UNIT
→
RAT.S
to YES. The duct supply air
temperature (SAT) may be used to replace the SAT sensor that
is internal to the unit. A supply duct SAT measurement is valid
for heating mode display while the factory-standard internal
SAT is not valid for heating due to its location upstream of the
heating section. When installing the supply duct SAT, the unit
must be configured by setting
Configuration
→
UNIT
→
SAT.H
to ENBL. A SAT sensor in the supply duct is the preferred con-
figuration for systems with Carrier VVT® controls.
SPACE HUMIDITY SENSOR — The space relative humidi-
ty sensor (part no. HL39ZZ005 duct mount or HL39ZZ007
wall mount) is a field-installed accessory. The space relative
humidity (RHS) may be selected for display only if the outdoor
air quality sensor (OAQ) is not used. When installing the rela-
tive humidity sensor, the unit must be configured by setting
Configuration
→
UNIT
→
RH.S
to YES.
ELECTRIC HEAT — The electric heat accessory depends on
model size, voltage, and heater kW size. When field installing
this accessory, the unit must be configured for electric heat by
setting
Configuration
→
HEAT
→
HT.TY
to a value of 2.
Summary of Contents for 48PG24
Page 68: ...68 Fig 14 Low Voltage Control Schematic 48PG20 28 Units without Humidi MiZer System a48 7627...
Page 69: ...69 Fig 15 Low Voltage Control Schematic 48PG20 28 Units with Humidi MiZer System a48 8227...
Page 70: ...70 Fig 16 Low Voltage Control Schematic 50PG20 28 Units without Humidi MiZer System a48 7778...
Page 71: ...71 Fig 17 Low Voltage Control Schematic 50PG20 28 Units with Humidi MiZer System a50 8101...
Page 72: ...72 Fig 18 Power Schematic Units without Humidi MiZer System a48 7628...
Page 73: ...73 Fig 19 Power Schematic Units with Humidi MiZer System a48 8228...
Page 74: ...74 Fig 20 Component Arrangement Units without Humidi MiZer System a48 8229...
Page 75: ...75 Fig 21 Component Arrangement Units with Humidi MiZer System a48 8230...
Page 105: ......