14
two 2-conductor 20 AWG twisted-pair cables (see Table 9) to
connect the field-supplied separate isolated 24 vac power
source to the sensor and to connect the sensor to the control
terminals. To connect the sensor to the control, identify the
positive (+) and ground (GND) terminals on the sensor and
connect the positive terminal to the RH/IAQ terminal on the
control and connect the ground terminal to terminal GND.
HUMIDITY
SENSOR
(Wall-Mounted)
INSTALLA-
TION — The accessory space humidity sensor is field sup-
plied and installed on an interior wall to measure the relative
humidity of the air within the occupied space. See Fig. 22.
The use of a standard 2 x 4-in. electrical box to accommo-
date the wiring is recommended for installation. The sensor can
be mounted directly on the wall, if acceptable by local codes.
If the sensor is installed directly on a wall surface, install the
humidity sensor using 2 screws and 2 hollow wall anchors
(field-supplied);
do not overtighten screws
.
The sensor must be mounted vertically on the wall. The
Carrier logo should be oriented correctly when the sensor is
properly mounted.
DO NOT mount the sensor in drafty areas such as near heat-
ing or air-conditioning ducts, open windows, fans, or over heat
sources such as baseboard heaters, radiators, or wall-mounted
light dimmers. Sensors mounted in those areas will produce
inaccurate readings.
Avoid corner locations. Allow at least 4 ft between the sen-
sor and any corner. Airflow near corners tends to be reduced,
resulting in erratic sensor readings.
Sensor should be vertically mounted approximately 5 ft up
from the floor, beside the space temperature sensor.
For distances up to 500 feet, use a 3-conductor, 18 or
20 AWG cable. A CCN communication cable can be used,
although the shield is not required. The shield must be removed
from both ends of the cable if this cable is used.
Do NOT clean or touch the sensing element with chemical
solvents; they can permanently damage the sensor.
Fig. 20 — Ventilation Rates Based on
CO
2
Set Point
Fig. 19 — Indoor Air Quality Sensor
(Wall-Mounted Version Shown) 33ZCSENCO2
35 in-lb (4 Nm)
80...110s
H F 2 3 B J 0 4 2
M a d e i n S w i t z e r l a n d
b y B e l i m o A u t o m a t i o n
1
0
yel
blu
ora
WIP
5K
LISTED
94D5
TEMP. IND. &
REG. EQUIP.
UL
Class 2 Supply
L R 9 2 8 0 0
NEMA2
24VAC/DC
50/60Hz
3VA
2W
COM
1
2
3
blk
red
wht
LINE VOLTAGE
24VAC
SEPARATE
POWER
SUPPLY
REQUIRED*
IAQ
GND
21
87
*Do not connect to the same transformer that supplies power to the zone controller.
Fig. 21 — Indoor Air Quality Sensor Wiring
Summary of Contents for 35L Series
Page 19: ......