
28
the IAQ Switch Input Config (
Configuration
AIR.Q
II.CF
).
Enthalpy and IAQ are controlled by the same switch input and
therefore cannot be used simultaneously.
II.CF = 0 (No IAQ)
The
II.CF = 0
configuration signifies that there is no IAQ
switch input. The damper will operate at the Econ Min at Max
Fan Speed (
Configuration
ECON
MP.MX
) and corre-
sponding damper position curve based on indoor fan speed
when the space is occupied and the indoor fan is on.
II.CF = 1 (DCV Normally Open) or II.CF = 2 (DCV Nor-
mally Closed)
The Demand Controlled Ventilation (DCV) allows the econo-
mizer minimum position to be decreased when there is no IAQ
problem. If IAQ is low, the economizer minimum position is
Econo Min IAQ Position (
Configuration
AIR.Q
AQ.MN
)
when the indoor fan is operating at Supply Fan Maximum
Speed (
Configuration
UNIT
FS.MX
). If IAQ is high, the
economizer minimum position is Econ Min at Max Fan Speed
(
Configuration
ECON
MP.MX
) when the indoor fan is op-
erating at Supply Fan Maximum Speed (
FS.MX
). If the fan
speed is modulating, see Fig. 8 for higher or lower damper po-
sition setting at the specific fan speed.
II.CF = 3 (Override Normally Open) or II.CF = 4 (Override
Normally Closed)
The damper override function permits absolute positioning of
the economizer damper for ventilation purposes. The override
is active when IAQ is high and inactive when IAQ is low. The
override position is configured by the IAQ Override Position
(
Configuration
AIR.Q
OVR.P
).
OUTDOOR AIR QUALITY (ANALOG INPUT)
The
Comfort
Link control can be configured for outdoor air
quality sensors which provide a 4 to 20 mA signal correspond-
ing to 0 to 2000 ppm CO
2
. If a field supplied sensor has a dif-
ferent range, the ppm display range must be reconfigured by
entering new values for the OAQ Sensor Value at 4mA (
Con-
figuration
AIR.Q
O.4M
) and OAQ Sensor Value at 20mA
(
Configuration
AIR.Q
O.20M
).
OA.CF = 0 (No OAQ)
This signifies that there is no outdoor air sensor installed. The
default value of OAQ is 400 ppm CO
2
when using demand
controlled ventilation (DCV).
OA.CF = 1 (DCV)
The outdoor air quality sensor analog input is the value of
OAQ for demand controlled ventilation (DCV).
OA.CF = 2 (OAQ Lockout)
The outdoor air quality analog input is only used to lock out the
outdoor ventilation. The economizer commanded position is
set to 0% when the CO
2
ppm exceeds the OAQ lockout value
configured for the OAQ Lockout Limit (
Configura-
tion
AIR.Q
OAQ.L
). The default value for OAQ Lockout
Limit (
OAQ.L
) is 600 ppm CO
2
.
FAN ENABLE (ANALOG IAQ SENSOR)
The DCV algorithm will operate whenever the building is oc-
cupied and the indoor fan is operating or whenever the IAQ al-
gorithm has caused the indoor fan to operate. The IAQ Analog
Fan Config (
Configuration
AIR.Q
IA.FN
) determines
whether or not the IAQ algorithm can turn on the indoor fan. If
the indoor fan is not operating, the economizer position will be
zero. The damper position may exceed Econ Min at Max Fan
Speed (
Configuration
ECON
MP.MX
) and corresponding
damper position curve to provide economizer cooling.
IA.FN = 0 (Never)
When
IA.FN = 0
, the IAQ algorithm can never turn on the fan.
IA.FN = 1 (Occupied)
When
IA.FN =1
, the IAQ algorithm will turn on the indoor fan
whenever the building is occupied and IAQ/OAQ differential
is greater than the Fan On AQ Differential (
Configura-
tion
AIR.Q
DF.ON
). The indoor fan will turn off when the
IAQ/OAQ differential is less than the Fan Off AQ Differential
(
Configuration
AIR.Q
DF.OF
).
IA.FN = 2 (Always)
The indoor fan operation for
IA.FN = 2
, is the same as the op-
eration when
IA.FN =1
, except the algorithm is not limited to
the occupied periods only. The fan can be triggered on when
the space is occupied or unoccupied.
FAN ENABLE (SWITCH INPUT)
The DCV algorithm will operate whenever the building is oc-
cupied and the indoor fan is operating or whenever the IAQ al-
gorithm has caused the indoor fan to operate. The IAQ Switch
Fan Config (
Configuration
AIR.Q
II.FN
) determines
whether or not the IAQ algorithm can turn on the indoor fan. If
the indoor fan is not operating, the economizer position will be
zero. The damper position may exceed Econ Min at Max Fan
Speed (
Configuration
ECON
MP.MX
) and corresponding
damper position curve to provide economizer cooling.
II.FN = 0 (Never)
When the
II.FN = 0
, the IAQ algorithm can never turn on fan.
II.FN = 1 (Occupied)
When
II.FN =1
, the IAQ algorithm will turn on the indoor fan
whenever the building is occupied and IAQ is high. The indoor
fan will turn off when the IAQ returns to normal.
II.FN = 2 (Always)
The indoor fan operation for
II.FN =2
is the same as the opera-
tion when
IA.FN =1
, except the algorithm is not limited to the
occupied periods only. The fan can be triggered on when the
space is occupied or unoccupied.
Optional Humidi-MiZer
®
Dehumidification System
Units with the factory-equipped Humidi-MiZer option are capa-
ble of providing multiple modes of improved dehumidification
as a variation of the normal cooling cycle. The Humidi-MiZer
option includes additional valves in the liquid line and discharge
line of each refrigerant circuit, a reheat coil downstream of the
evaporator, and Motormaster
®
variable-speed control of some or
all outdoor fans. The Humidi-MiZer Equipped (
Configura-
tion
HMZR
REHT
) configuration is factory set to Yes for
Humidi-MiZer equipped units. This enables Humidi-MiZer op-
erating modes and service test.
Humidi-MiZer operation requires installation and configuration
of either a space relative humidity sensor or a relative humidity
switch input. Space Humidity Switch (
Configura-
tion
UNIT
RH.SW
) set to 1 for use of a normally open
switch or 2 for normally closed switch. The switch is wired to
field connection terminal board terminal labeled HUM and the
“R2” terminal. Set RH Sensor on OAQ Input (
Configura-
tion
UNIT
RH.S
) to Yes for use of a 4 to 20 mA output RH
sensor wired to field connection terminal board (TB) terminals
SPRH and LPWR (for loop powered). RH Sensor Value at 4ma
(
Configuration
AIR.Q
H.4M
) sets the % display for a 4mA
input from the relative humidity sensor. RH Sensor Value at
20ma (
Configuration
AIR.Q
H.20M
) sets the % display for
a 20mA input from the relative humidity sensor.
DEHUMIDIFICATION DEMAND
When using a humidistat or switch input, the demand for de-
humidification is seen as Space Humidity Switch (
In-
puts
GEN.I
HUM
) being Low or High. A low value
means humidity level is good and a high value means that
dehumidification is needed.When using an RH sensor, the
demand is based on the Space Humidity Sensor (
In-
puts
AIR.Q
SP.RH
) value compared to the Space RH
Summary of Contents for /50HC 04-28
Page 69: ...69 Fig 24 Typical Control Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 70: ...70 Fig 25 Typical Power Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 71: ...71 Fig 26 Typical Control Diagram for 50HC 04 14 Units 50HC 14 shown ...
Page 72: ...72 Fig 27 Typical Power Diagram for 50HC 04 14 Units 50HC 14 Non Humidi MiZer shown ...
Page 73: ...73 Fig 28 Typical Control Diagram 48HC 17 28 Units ...
Page 74: ...74 Fig 29 Typical Control Diagram 50HC 17 28 Units ...
Page 75: ...75 Fig 30 Typical Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 76: ...76 Fig 31 Typical Non Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 89: ...89 Fig 42 Modulating ERV Wiring Schematic ...
Page 90: ...90 Fig 43 EnergyX ERV Control Box Component Layouts ...
Page 101: ...101 Fig 59 Exhaust Fan Assembly Removal Exhaust Fan Assembly ...
Page 141: ......