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Fig. 14. Hookup diagram for 3-wire zone valves in Series 20 heating system with zone controls.
S1
S
T1
T
OUT
OUT
LED
G
Y2
Y1
W1
W2
1
2
3
4
GND
C
R
RH
RC
HUM
HUM
VNT
VNT
W8900A,C
L1
(HOT)
L2
1
2
4
7
5
6
1
2
3
4
5
6
7
8
8
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
JUMPER R TO RH TO RC FOR SINGLE TRANSFORMER APPLICATIONS.
DURING INSTALLER SETUP, CONFIGURE PC8900 FOR HUMIDITY CONTROL IN HEATING MODE
(HUMIDIFIER) OR COOLING MODE (DEHUMIDIFIER).
W8900 ALLOWS CONNECTION OF A CO MONITOR WITH UNCOMMITTED CONTACTS.
USE ONE R8239 FOR EVERY FOUR ZONES.
USE FOR 3-WIRE ZONE VALVE OR DAMPERS.
ZONES 2, 3, 4 CAN BE CONTROLLED BY ADDITIONAL PC8900/W8900 OR OTHER THERMOSTATS.
SEE VENTILATION INSTRUCTIONS FOR WIRING.
GROUNDING THE GND TERMINAL IS NOT RECOMMENDED.
CONNECTION FOR CM8900A REMOTE COMMUNICATIONS MODULE.
PC8900
1
2
3
4
CO
2
MONITOR
M4491D
C
Y
R
G
R8239A1052
24V
W
W
G
C
R
W
G
C
R
W
G
C
R
R8222B1067
6
R8222B1067
6
R8222B1067
ZONE 2
VALVE
ZONE 3
VALVE
ZONE 4
VALVE
ZONE 1
VALVE
ZONE 2 THERMOSTAT
7
ZONE 3 THERMOSTAT
7
ZONE 4 THERMOSTAT
3
HUMIDIFIER OR
DEHUMIDIFIER
EQUIPMENT
VENTILATION
EQUIPMENT
C7189A REMOTE AIR
TEMPERATURE SENSOR
C7100 DISCHARGE AIR
TEMPERATURE SENSOR
C7089A OUTDOOR AIR
TEMPERATURE SENSOR
CO
2
2
10
9
10
9