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38MARB: 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.
Recommended Connection Method for Power and
Communication Wiring:
The main power is supplied to the outdoor unit. The field supplied 14/3
power/communication wiring, from the outdoor unit to the indoor unit,
consists of four (4) wires and provides the power for the indoor unit. Two
wires are high voltage AC power, one is communication wiring and the
other is a ground wire. Wiring between 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 exists, a 14/2 stranded shielded wire can be used to
replace L2 and (S) between outdoor unit and indoor unit landing the
shield onto ground in the outdoor unit only.
NOTE: Matches with multi-family and residential fan coils require
separate power for the indoor and outdoor unit. A 24V interface kit
is required for compatibility. Refer to the
24V Interface Kit
installation manual.
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