Carrier 48FC 08-16 Series - Indoor Air Quality (IAQ) Sensor Input

54
Fig. 77 — Return Air Temperature or Enthalpy
Sensor Mounting Location
Fig. 78 — EconoMi$er
®
IV W7212 Control
Fig. 79 — Enthalpy Changeover Set Points
Indoor Air Quality (IAQ) Sensor Input
The IAQ input can be used for demand controlled ventilation
control based on the level of CO
2
measured in the space or
return air duct.
Mount the accessory IAQ sensor according to manufacturer speci-
fications. The IAQ sensor should be wired to the AQ and AQ1 ter-
minals of the controller. Adjust the DCV potentiometers to corre-
spond to the DCV voltage output of the indoor air quality sensor at
the user-determined set point. See Fig. 80.
If a separate field-supplied transformer is used to power the IAQ
sensor, the sensor must not be grounded or the EconoMi$er
®
IV
control board will be damaged.
When using demand controlled ventilation, the minimum
damper position represents the minimum ventilation position
for VOC (volatile organic compounds) ventilation require-
ments. The maximum demand ventilation position is used for
fully occupied ventilation.
When demand controlled ventilation is not being used, the mini-
mum position potentiometer should be used to set the occupied
ventilation position. The maximum demand ventilation position
should be turned fully clockwise.
Fig. 80 — CO
2
Sensor Maximum Range Settings
EconoMi$er IV
EconoMi$er IV
Controller
Grommet
Return Air
Sensor
Return Duct
(Field-Provided)
TR1
24 Vac
COM
TR
24
Va c
HOT
12
3
4
5
EF
EF1
+
_
P1
T1
P
T
N
EXH
2V 10V
EXH
Set
Set
2V 10V
2V 10V
DCV
DCV
Free
Cool
B
C
A
D
SO+
SR+
SR
SO
AQ1
AQ
DCV
Min
Pos
Open
Max
N1
CONTROL
CURVE
A
B
C
D
CONTROL POINT
APPROX.
°F (°C)
AT 50% RH
73 (23)
70 (21)
67 (19)
63 (17)
1
2 1
4
1
6
1
8 20
2
2
2
4
26
28
3
0
32
3
4
3
6
38 4
0
42
4
4
4
6
9
0
1
0
0
80
70
60
50
4
0
30
2
0
10
E
NT
HALP
Y BTU PER POUND DRY AIR
85
(29)
90
(32)
95
(35)
100
(38)
105
(41)
110
(43)
35
(2)
35
(2)
40
(4)
40
(4)
105
(41)
110
(43)
45
(7)
45
(7)
50
(10)
50
(10)
55
(13)
55
(13)
60
(16)
60
(16)
65
(18)
65
(18)
70
(21)
70
(21)
75
(24)
75
(24)
80
(27)
80
(27)
85
(29)
90
(32)
95
(35)
100
(38)
A
A
B
B
C
C
D
D
R
ELATIVE HU
MIDITY (%)
HIGH LIMIT
CURVE
APPROXIMATE DRY BULB TEMPERATURE °F (°C)
0
1000
2000
3000
4000
5000
6000
2345678
Range Configuration (ppm)
Damper Voltage for Maximum Ventilation Rate
CO Sensor Max Range Setting
800 ppm
900 ppm
1000 ppm
1100 ppm