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Installation Manual
Due to our policy of continuous product innovation, some specifications may change without notification.
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WIRING
Power wiring is field supplied. Wire size is selected based on the larger MCA value, and must comply with the applicable local and national codes.
6. Connect the power wiring to the terminal block connections. Ensure the screws securely connect the wire to the terminals and are not
loose.
7. Ensure the field-provided communications cable is connected to the 3(A) and 4(B) terminal block connections. Polarity matters on the
outdoor unit to indoor unit / heat recovery unit communications bus, and must be maintained throughout the entire system. Be sure to con-
nect 3(A) terminals to A terminals and 4(B) terminals to B terminals. Refer to the preceeding pages for indoor unit wiring connections, the
Outdoor Unit Installation Manual for information regarding the outdoor unit and heat recovery unit wiring connections, or review the wiring
diagrams on the applicable units.
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Cross connecting the 3(A) and 4(B) terminals will cause communications errors and system malfunction.
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Field-provided communication cable between Master ODU to IDUs / HRUs to be 18 AWG, 2-conductor, twisted, stranded, shielded. Ensure
the communication cable shield is properly grounded to the Master ODU chassis only. Shield must be tied together so it is continuous and
insulated to prevent grounding against IDU/HRU electrical cabinet.
Do not ground the ODU to IDUs / HRUs communication cable at any
other point. Wiring must comply with all applicable local and national codes.
8. If a remote controller is to be installed, connect the remote controller’s cable to the indoor unit’s remote controller connection. Controller
connections depend on type of indoor unit being installed. Some indoor units use terminal block connections; other indoor units use Molex
connections. See the wiring diagram for the specific indoor unit.
Connection Procedure