37
*Sylk is a trademark of Honeywell International Inc.
 
S-Bus Sensor Wiring
The labels on the sensors and controller are color coded for ease of
installation. Orange labeled sensors can only be wired to orange
terminals  on  the controller.  Brown  labeled  sensors  can  only  be
wired to S-bus (brown) terminals. Use Fig. 49 and Table 17 to lo-
cate the wiring terminals for each S-Bus sensor.
Use Fig. 48 and Table 17 to locate the wiring terminals for each
enthalpy control sensor.
Fig. 49 — S-Bus Sensor DIP Switches
Use Fig. 49 and Table 18 to set the DIP switches for the desired
use of the sensor.
NOTE:  When an  S-Bus sensor is  connected to an existing net-
work, it will  take 60  minutes  for the network to recognize  and
auto-configure itself to use the new sensor.
During the 60 minute setup period, no alarms for sensor failures
(except SAT) will be issued and no economizing function will be
available.
CO
2
 Sensor Wiring
When using a CO
2
 sensor the black and brown common wires are
internally connected and only one is connected to “IAQ COM” on
the W7220. Use the power from the W7220  to power the CO
2
sensor OR make sure the ground for the power supplies are com-
mon. See Fig. 50 for CO
2
 sensor wiring.
Table 15 —  Economizer Module - Left Hand Terminal 
Blocks
LABEL TYPE DESCRIPTION
Top Left Terminal Block
MAT
MAT
20k NTC 
and COM
Mixed Air Temperature Sensor (Polarity 
Insensitive Connection)
OAT
OAT
20k NTC 
and COM
Outdoor Air Temperature Sensor (Polarity 
Insensitive Connection)
S-BUS
S-BUS
S-BUS 
(Sylk* Bus)
Enth
alpy Control Sensor 
(Polarity Insensitive Connection)
Bottom Left Terminal Block
IAQ 2-10 2-10 vdc
Air Quality Sensor Input (e.g. CO
2
 
sensor)
IAQ COM COM Air Quality Sensor Common
IAQ 24V 24 vac Air Quality Sensor 24 vac Source
ACT 2-10 2-10 vdc Damper Actuator Output (2-10 vdc)
ACT COM COM Damper Actuator Output Common
ACT 24v 24 vac Damper Actuator 24 vac Source
Table 16 — Economizer Module - Right Hand 
Terminal Blocks
LABEL TYPE DESCRIPTION
Top Right Terminal Block
s
AUX2 I 24 vac IN The first terminal is not used.
OCC 24 vac IN
Shut Down (SD) or HEAT (W) 
Conventional only
and
Heat Pump Changeover (O-B) in Heat 
Pump mode.
E-GND E-GND Occupied/Unoccupied Input
EXH1 24 vac OUT Exhaust Fan 1 Output
AUX1 O 24 vac OUT
Programmable:
Exhaust fan 2 output
or
ERV
or
System alarm output
Bottom Right Terminal Blocks
Y2-I 24 vac IN
Y2 in - Cooling Stage 2 Input from space 
thermostat
Y2-O 24 vac OUT
Y2 out - Cooling Stage 2
 Output to stage 
2 mechanical cooling
Y1-I 24 vac IN
Y1 in - Cooling Stage 2 Input from space 
thermostat
Y1-O 24 vac OUT
Y1 out - Cooling Stage 2 Output to stage 
2 mechanical cooling
C COM 24 vac Common
R 24 vac 24 vac Power (hot)
Table 17 —  HH57AC081 Sensor Wiring Terminations
TERMINAL
TYPE DESCRIPTION
NUMBER LABEL
1 S-BUS S-BUS
S-BUS 
Communications 
(Enthalpy Control 
Sensor Bus)
2 S-BUS S-BUS
S-BUS 
Communications 
(Enthalpy Control 
Sensor Bus)
Table 18 —  HH57AC081 Sensor DIP Switch
USE
DIP SWITCH POSITIONS FOR SWITCHES 1, 2, AND 3
1 2 3
DA OFF ON OFF
RA ON OFF OFF
OA OFF OFF OFF
DIP
SWITCH
LABEL
DIP
SWITCHES
(3)
S-BUS
2 PIN SIDE
CONNECTOR
S-BUS
TERMINALS
(1 AND 2)