Service Manual

50
Fig. 36 – Observer Communicating Wall Control Four - Wire Connection Wiring Diagrams
(See Thermostat Installation Instructions for specific unit combinations)
S1
S2
R
C
DX-
DX+
Optional Remote
Room Sensor
HUM
COM
C
DX-
DX+
Humidifier
Connection
Green
Yellow
White
Red
R
Wall Control
Variable Speed
Furnace/Fan Coil
Outdoor
Green
Yellow
White
Red
LEGEND
24V FACTORY WIRING
24V FIELD WIRING
FIELD SPLICE CONNECTION
C
DX-
DX+
R
Fig. 37 – Non- Communicating Standard Thermostat 3- Wire 24V Circuit Connections
(See Thermostat Installation Instructions for
Specific Unit combinations)
LEGEND
24- V FACTORY WIRING
24- V FIELD WIRING
FIELD SPLICE CONNECTION
ELECTRICAL OPERATION HAZARD
Failure to follow this caution may result in
equipment damage or improper operation.
A minimum of three wire thermostat wiring is
required for the system to operate.
CAUTION
!