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SAT
20-K OHM
PNO HH79NZ007
(1)
OAT
20-K OHM
PNO HH79NZ007
CO
SENSOR
2
(1)
If no Enthalpy sensor connected
ENTHALPY
SENSOR
1
1
2 3 4
ECONO
ACTUATOR
Economizer Control Configurations
Enthalpy Changeover Control —
Economizer changeover based on outdoor air enthalpy
requires an outdoor air enthalpy sensor to replace the OAT
sensor.
The
enthalpy
factory- - installed option or as a field- - installed accessory (part
number HH57AC081). See Fig. 1 for model number
nomenclature; check Position #15 for codes N or R
indicating a factory- - installed enthalpy sensor. Use Fig. 52
1
MAT
BRN
2
MAT
ORN
1
OAT
PNK
2
OAT
VIO
1
GRA
S - BUS
CONTROLLER
2
GRA
S - BUS
1
BLK
IAQ - 2 - 10
2
BLU
IAQ COM
3
IAQ 24V+
1
ACT - 2 - 10
2
ACT COM
BLK
3
BLU
ACT 24V+
4
Fig. 50 - - W7220 Sensor and Control I/O Connections
1
2
BRN
2
ORN
1
PNK
2
VIO
1
GRA
2
GRA
1
BLK
2
BLU
3
1
2
BLK
3
BLU
4
Fig. 51 - - Actuator/S- - BUS
sensor
is
available
as
W1
AUX2-I
OCC
W7220
E- GND
EXH 1
AUX1-O
Y2 - I
Y2 - O
Y1 - I
Y1 - O
C
R
MAT
MAT
OAT
OAT
W7220
S - BUS
CONTROLLER
S - BUS
IAQ - 2 - 10
IAQ COM
IAQ 24V+
ACT - 2 - 10
ACT COM
ACT 24V+
and Table 11 to select the enthalpy changeover setting to
enter in menu item SETPOINTS - - > ENTH CURVE.
Enthalpy Settings —
When the OA temperature, enthalpy and dew point are
below the respective setpoints, the Outdoor Air can be
a
used for economizing. Fig. 52 shows the new single
enthalpy boundaries in the W7220. There are 5 boundaries
(setpoints ES1 through ES5), which are defined by dry
bulb temperature, enthalpy and dew point.
Refer to Table 11 for ENTH CURVE setpoint values.
40
6
5
TSTAT W1
WHT
4
OCCUPANCY --- TSTAT G
BLK
3
GROUND
GRN/YEL
2
POWER EXHAUST RELAY
VIO
1
6
TSTAT Y3
YEL
5
ORN
4
TSTAT Y1
BLU
3
ECON
(2)
GRA
2
24-V COM
BRN
1
24-V POWER
RED
(2)
24V @ Y1-0 means Stage 1 mechanical cooling
6
5
W1
AUX2-I
WHT
4
OCC
BLK
3
E- GND
GRN/YEL
2
EXH 1
VIO
1
AUX1-O
6
Y2 - I
YEL
5
Y2 - O
ORN
4
Y1 - I
BLU
3
Y1 - O
GRA
2
C
BRN
1
R
RED
OFF STATUS
a48--- 9347
a48--- 9348
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