High-Level Wiring Path; Wiring Diagram - Fully Communicating System Components - Johnson Controls Hx 3 S1-THXU430W Installation Manual

5407934-UIM-C-1119
The system is connected by four wires. Two of the wires are used to
bring power to the individual controls (R and C), and two of the wires are
used for serial communication (A+ and B-).
Variable capacity outdoor units only require three wires. Variable capac-
ity equipment has its own transformer, so it does not require an R con-
nection between the indoor and outdoor equipment.
FIGURE 3: High-Level Wiring Path
Touch Screen
Communicating
Control
A+
R
C
B-
DO NOT connect to variable capacity outdoor equipment.
FIGURE 4: Wiring Diagram - Fully Communicating System Components
Johnson Controls Ducted Systems
VS Air Handler/Furnace
Communicating
Control
A+
R
GND
B-
Air Conditioner/Heat Pump
Communicating
Control
A+
R
C
B-
A0611-002
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