Unblocking The Unit Safely In Case Of Breakdown - York VAC 20A Quick Installation Manual

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.
The control board indicates the faults detected by
means of the red V3 LED on the board or the fault
codes indicated on the DPC-1 thermostat.
N O T E
For further information, see the technical information
on the YKN2 Open control board.
Rotational direction of Scroll compressors
The Scroll compressors and the fans only operate correctly if they rotate in the correct direction. All of
the motors and compressors in the unit are connected so that they rotate correctly.
If the compressors are not connected correctly and are rotating in the wrong direction:
• The compressor will not compress.
• Operating noise will be abnormal.
• Electricity consumption (A) will be low.
• They overheat.

1.7 Unblocking the unit safely in case of breakdown

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.
To unlock the unit, see "Restarting the HVAC unit in case of fault" in the User Manual.
If the thermostat display keeps showing the pilot light
-1- and any fault code -2- or if the air conditioning unit
does not start, contact a Johnson Controls Inc.
Authorised Technical Assistance Service.
Unblocking the unit safely in case of breakdown
AUTO
AUTO
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Quick installation guide
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