Honeywell PC8900A - Page 10

68-0173—310
Fig. 12. Hookup diagram for 1-stage or 2-stage heating and cooling in conventional system with single transformer.
L1
(HOT)
L2
1
1
2
3
4
5
5
3
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.
SEE VENTILATION INSTRUCTIONS FOR WIRING.
GROUNDING THE GND TERMINAL IS NOT RECOMMENDED.
CONNECTION FOR CM8900A REMOTE COMMUNICATIONS MODULE.
STAGE 1
HEAT RELAY
STAGE 2
HEAT RELAY
STAGE 1
COOL RELAY
STAGE 2
COOL RELAY
FAN RELAY
PC8900
1
2
3
4
CO
2
MONITOR
M4478D
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
2
4
C7189A REMOTE AIR
TEMPERATURE SENSOR
C7100 DISCHARGE AIR
TEMPERATURE SENSOR
C7089A OUTDOOR AIR
TEMPERATURE SENSOR
HUMIDIFIER
OR DEHUMIDIFIER
EQUIPMENT
VENTILATION
EQUIPMENT
SYSTEM
TRANSFORMER
CO
2
2
7
7
6
6