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10
WIRING
All wires must be sized per NEC (National Electrical Code) or
CEC (Canadian Electrical Code) and local codes. Use the Electrical
Data table MCA (minimum circuit amps) and MOCP (maximum
over current protection) to correctly size the wires and the
disconnect fuse or breakers respectively.
Per the caution note, only copper conductors with a 600 volt
insulation rating wire must be used.
Sizes 18−42
Recommended Connection Method for Power and
Communication Wiring:
The main power is supplied to the outdoor unit. The field supplied
14/3 stranded wire with ground with a 600 volt insulation rating,
power/communication wiring from the outdoor unit to indoor unit
consists of four (4) wires and provides the power for the indoor
unit. Two wires are line voltage AC power, one is communication
wiring (S) and the other is a ground wire.
Wiring between the indoor and outdoor unit is polarity sensitive.
The use of BX wire is NOT recommended.
If installed in a high Electromagnetic field (EMF) area and
communication issues exist, a 14/2 stranded shielded wire can be
used to replace L2 and (S) between the outdoor and indoor unit
landing the shield onto the ground in the outdoor unit only.
Sizes 48−56
Recommended Connection Method for Power and
Communication − Wiring − Power and Communication
Wiring:
Power Wiring OUTDOOR UNIT& BRANCH BOXES:
Separate power supplies are required for the OUTDOOR UNIT
and the BRANCH BOXES. The indoor units are powered by the
Branch Boxes. The field supplied 14/3 stranded wire (with ground)
with a 600 volt insulation rating, power/communication wiring
from the BRANCH BOXES to INDOOR UNITS consists of four
(4) wires and provides the indoor unit’s power. Two wires are line
voltage AC power; one is communication wiring (S) and the other
is a ground wire.
Wiring between the indoor unit and the branch box is polarity
sensitive.
The use of BX wire is NOT recommended.
Up to three (3) Branch Boxes can be powered from the same 15
amp breaker.
Communication Wiring:
A separate shielded copper conductor only, must be used as the
communication wire from the OUTDOOR UNIT to the
BRANCH BOX.
Please use a separate shielded 16GA stranded control wire.
See the wiring diagram in the wiring diagram section for sizes
48−56.
CAUTION
!
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
S
Wires should be sized based on NEC and local codes.
S
Use copper conductors only with a 600 volt insulation
rating wire.
CAUTION
!
EQUIPMENT DAMAGE HAZARD
S
Be sure to comply with local codes while running wire
from the indoor unit to the outdoor unit.
S
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.
S
No wire should touch the refrigerant tubing, compressor
or any moving parts.
S
Disconnecting means must be provided and shall be
located within sight and readily accessible from the air
conditioner.
S
Connecting cable with conduit must be routed through the
hole in the conduit panel.