Carrier 48/50AJ Air Conditioner User Manual


 
68
IQ.A.C = 4 (10K potentiometer minimum position) —
With a 10K linear potentiometer connected to TB5-6 and 7,
the economizer minimum position will be scaled linearly
from 0% (0 kilo-ohms) to EC.MX (10 kilo-ohms).
IAQ Analog Fan Config (
Configuration
IAQ
AQ.CF
IQ.A.F) — This configuration is used to configure the control
of the indoor fan. If this option is used then the IAQ sensor
must be in the space and not in the return duct. It has the fol-
lowing configurations:
IQ.A.F = 0 (No Fan Start) — IAQ demand will never
override normal indoor fan operation during occupied or
unoccupied period and turn it on.
IQ.A.F = 1 (Fan On If Occupied) — IAQ demand will
override normal indoor fan operation and turn it on (if
off) only during the occupied period (CV operation with
automatic fan).
IQ.A.F = 2 (Fan On Occupied/Unoccupied) — IAQ
demand will always override normal indoor fan operation
and turn it on (if off) during both the occupied and unoccu-
pied period. For IQ.A.F = 1 or 2, the fan will be turned on as
described above when DAQ is above the DAQ Fan On Set
Point (Configuration
IAQ
AQ.SP
D.F.ON). The fan
will be turned off when DAQ is below the DAQ Fan Off Set
Point (Configuration
IAQ
AQ.SP
D.F.OF). The con-
trol can also be set up to respond to a discrete IAQ input.
The discrete input is connected to TB5-6 and 7.
IAQ Discrete Input Config (
Configuration
IAQ
AQ.CF
IQ.I.C) — This configuration is used to set the type of IAQ
sensor. The following are the options:
IQ.I.C = 0 (No Discrete Input) — This is used to indicate
that no discrete input will be used and the standard IAQ
sensor input will be used.
IQ.I.C = 1 (IAQ Discrete Input) — This will indicate
that the IAQ level (high or low) will be indicated by
the discrete input. When the IAQ level is low, the
economizer minimum position will be Configuration
IAQ
DCV.C
IAQ.M.
IQ.I.C = 2 (IAQ Discrete Input with Minimum Position
Override) — This will indicate that the IAQ level (high
or low) will be indicated by the discrete input and the
economizer minimum position will be the IAQ override
position, IQ.O.P (when high).
It is also necessary to configure how the fan operates when
using the IAQ discrete input.
IAQ Discrete Fan Config (
Configuration
IAQ
AQ.CF
IQ.I.F) — This is used to configure the operation of the
fan during an IAQ demand condition. It has the following
configurations:
IQ.I.F = 0 (No Fan Start) — IAQ demand will never
override normal indoor fan operation during occupied or
unoccupied period and turn it on.
IQ.I.F = 1 (Fan On If Occupied) — IAQ demand will
override normal indoor fan operation and turn it on (if
off) only during the occupied period (CV operation with
automatic fan).
IQ.I.F = 2 (Fan On Occupied/Unoccupied) — IAQ
demand will always override normal indoor fan
operation and turn it on (if off) during both the occupied
and unoccupied period.
OAQ 4-20 mA Sensor Config (
Configuration
IAQ
AQ.CF
OQ.A.C) — This is used to configure the type of
outdoor sensor that will be used for OAQ levels. It has the fol-
lowing configuration options:
OQ.A.C = 0 (No Sensor) — No sensor will be used and
the internal software reference setting will be used.
OQ.A.C = 1 (OAQ Sensor with DAQ) — An outdoor
CO
2
sensor will be used.
OQ.A.C = 2 (4 to 20 mA Sensor without DAQ).
100
500
700
1000
INSIDE/OUTSIDE CO
2
DIFFERENTIAL
INSIDE CO
2
CONCENTRATION
AQ
DIFFERENTIAL
LOW (DAQ.L)
AQ
DIFFERENTIAL
HIGH (DAQ.H)
MINIMUM
IAQ
DAMPER
POSITION
ECONOMIZER
MINIMUM
DAMPER
POSITION
INCREASING VENTILATION
VENTILATION FOR PEOPLE
VENTILATION FOR SOURCES
Fig. 12 — IAQ Control
NOTE: Calculating the IAQ.M and EC.MN damper position based
on differential IAQ measurement.
Based on the configuration parameter IAQREACT, the reaction to
damper positioning based on differential air quality ppm can be
adjusted.
IAQREACT = 1 to 5 (more responsive)
IAQREACT = 0 (linear)
IAQREACT = –1 to –5 (less responsive)
Fig. 13 — IAQ Response Curve
A48-7209
A48-7711