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Thermostat Connection
The outdoor unit and the thermostat are connected by
means of a 10-pin x 0.22 mm
2
shielded
communication cable. Connect the cable to the
terminals indicated and firmly tighten the set screws.
Also consult the wiring diagrams for the unit and
Wiring diagrams
, see on page 39.
Fan connection for VIR 25A to 90A indoor units
Where the phase sequence is correct (R-S-T) and the fan rotates the wrong way, exchange two phases
at the bottom of the fan contactor.
Configuration of the electronic board
The unit is powered for start-up once the accessories have been installed. For the electronic board to
respond according to the accessories installed, press the "test" button for around two seconds until the
red LED switches off.
Cold only function selection
N O T E
Only use in the event of using the assembly as a cold-only unit with no heat pump
To configure the outdoor unit (VCH) in cold only mode:
• Configure micro-switch (S1) no. 5 and no. 4 on the YKN2 Open board to OFF.
• Disconnect the power supply to the board to read the new configuration.
1
Installation manual
1.10 Instructions for installation and connection of the unit
38