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38MBR: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
3
WIRING
All wires must be sized per NEC (National Electrical Code) or CEC
(Canadian Electrical Code) and local codes. Use 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.
Sizes 36-58 Recommended Connection Method for Power and
Communication Wiring
Power and Communication Wiring:
The main power is supplied to the outdoor unit. The field supplied power
wiring from the outdoor unit to the indoor unit consists of three (3) wires
and provides the power for the indoor unit. Two wires are high voltage
AC power and one is a ground wire. To minimize voltage drop, the
factory recommended wire size is 14/2 stranded with a ground.
Communication Wiring:
A separate shielded stranded copper conductor only, with a 600 volt
rating and double insulated copper wire, must be used as the
communication wire from the outdoor unit to the indoor unit. Please use a
separate shielded 16GA stranded control wire.
CONNECTION DIAGRAM
Fig. 1 — Connection Diagram
NOTES:
1. Do not use thermostat wire for any connection between indoor and outdoor units.
2. All connections between indoor and outdoor units must be as shown. The connections are sensitive to polarity and will generate a fault code.
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
Wires should be sized based on NEC 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.
CAUTION