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Given that the air conditioning unit is installed on the roof of a building or property, users must under no
circumstances inspect or adjust the unit themselves. All of inspections or adjustments that may be made
by the user are performed using the DPC-1 thermostat.
The air conditioning unit is fitted with electrical protection systems to protect personnel responsible for
its regular maintenance and upkeep.
As established by applicable electricity regulations, the electrical system is fitted with electricity surge
and current leakage protection system consisting of differential circuit breakers and thermal magnetic
switches (not supplied by the manufacturer, must be installed on site).
Under no circumstances is the user of the air conditioning unit exposed to live parts.
Likewise, access to moving parts by unauthorised persons is prevented. This involves placing
appropriate safety locks on all of the removable covers on the unit.
Unit protection systems
The refrigerant circuit of the unit is protected against excessively high or low pressure and discharge
temperature. It is also protected against repeated cold start-ups caused by the compressor suction probe
when the summer cycle is activated.
1.11 Instructions for starting up the unit
1.11.1 Electrical checks
D A N G E R
• All side panels except for that of the electrical box, must be fitted, closed and secured with their
corresponding locks before turning the general switch on the unit.
• The unit has a remote control, which means that the fan turbine may start unexpectedly.
C A U T I O N
Loose connection terminals produce overheating of cables and terminals. The unit will work incorrectly
and there is a risk of fire.
Check that the cables are firmly secured to their connection terminals.
C A U T I O N
Do not start the unit until all installation work has been completed.
Initial connection of the unit
Once all of the planned accessories are installed, and before starting the unit, its general switch on the
installation must be turned on.
Press the "Test" button for two seconds so that the unit recognises the installed accessories. When the
recognition process is complete, the red pilot light switches off.
YKN2 Open control board
The unit control software is in the YKN2 Open control board. The control algorithm can be configured or
changed by:
• The position of the micro-switches.
• The connection of accessories detected by the board.
Installation manual
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Instructions for starting up the unit 1.11
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