14
The W7220 controller provides the following:
• 2-line LCD interface screen for setup, configuration and
troubleshooting
• On-board fault detection and diagnostics
• Sensor failure loss of communications identification
• Automatic sensor detection
• Capabilities for use with multiple-speed indoor fan
systems
See Fig. 32 for wiring the W7220 controller for exhaust and fault
alarm.
Fig. 32 —
Wiring W7220 Controller for Exhaust and Fault Alarm
IMPORTANT: The default setting on the W7220 controller is
for a “Fan Type” with 2 speed, which is correct for 2 or 3 speed
units (48/50LC 14-26). If your unit is 1 (single) speed, the
setting under SYSTEM SETUP > FAN TYPE must be changed
to 1 speed.
ROOF TOP UNIT
Y1O
Y2O
Y1I
Y2I
OCC
24 VAC
E-GND
Y1
G
W2
W1
Y2
O/B
OCC
W7220 ECONOMIZER CONTROLLER MODULE
THERMOSTAT
CO2
SENSOR
2-10 VDC
(OPTIONAL)
MAT
MAT
OAT
OAT
C R
R(+)
C(-)
IAQ (2-10V)
IAQ COM
IAQ 24V
ACT (2-10V)
ACT COM
ACT 24V
3
1
2
OAT TEMP
SENSOR
20K NTC
MS3103J
OR MS3105J
1
1
MA TEMP
SENSOR
20K NTC
S-BUS
4
5
S-BUS
AUX1-0
AUX2-I
NOTE THAT THE 20K NTC SENSOR CAN BE MOUNTED IN THE OAT TERMINALS ONLY IN THIS CONFIGURATION
.
WHEN USING A HEAT PUMP THERMOSTAT, THERMOSTAT TERMINALS MAY DIFFER: W1 MAY BE LABELED O OR B AND W2 MAY BE LABELED W.
WHEN USING A HEAT PUMP WITH DEFROST FEEDBACK, ADD AN ISOLATION RELAY BETWEEN O AND C.
2
2
3
3
1K1
1K1
EXH1
EXHAUST
ANNUNCIATION –
LIGHT OR OTHER
C
24VAC
24VAC
WIRING W7220 FOR EXHAUST AND FAULT ALARM