Bryant 38MURA Manual page 83

38MURA: Product Data
Communication wiring
There are two options available to establish communication between the
outdoor unit and approved indoor unit.
OPTIONS
COMMUNICATION TYPE
Non-Polarity RS485
1
Communication (S1 - S2)
2 24V communication
S1 S2 B W D
R C Y1 Y2 L
CN6
TO INDOOR UNIT
Fig. 3 —Option 1: Non-polarity RS485 Communication
Outdoor Unit
Only Mode
S1 S2 B W D
R C Y1 Y2 L
CN6
TO 24V THERMOSTAT
Fig. 4 —Option 2: 24V Communication
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
RECOMMENDED CABLE SIZE
16 AWG (stranded shielded)
18 AWG 8 conductor thermostat
wire
S1
ON
1 2 3 4
S1
ON
1 2 3 4
83
NOTES:
1. Do not use the thermostat wire for any RS-485 connection between
indoor and outdoor units.
2. All connections between the indoor and outdoor units must be made as
shown in Figures 3 - 4.
CAUTION
Power needs to be OFF before dip switch adjustments.
WARNING
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage or
improper operation. Wires should be sized based on NEDC and
local codes.
CAUTION
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage or
improper operation. Be sure to comply with local codes while
running wire from the indoor unit to the outdoor unit. Every wire
must be connected firmly. Loose wiring may cause the terminal to
overheat or result in unit malfunction. A fire hazard may also exist.
Ensure all wiring is tightly connected.
No wire should touch the refrigerant tubing, compressor or any
moving parts. Disconnecting means must be provided and shall be
located within sight and readily accessible from the air conditioner.
Connecting cable with conduit shall be routed through the hole in
the conduit panel.
.