Buttons And Leds; Test Button; Leds - Johnson Controls York YKN2Open board Technical Information

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Buttons and LEDs

2.1 Buttons and LEDs
2.1 Buttons and LEDs

2.1.1 Test button

Situated on the main electronic board, it carries out different operations depending on how it is pressed:
• If it is kept pressed until the yellow LED is activated, certain timings are shortened and any fault
detected is reset.
• If it is kept pressed down until the red LED is activated, the optional accessories and probes connected
to the board are identified.

2.1.2 LEDs

There are three LED signalling diodes.
• The green LED indicates whether the unit is working properly or if there are incidents. If the unit is
working properly, this LED will flash at a constant frequency.
• The red LED indicates faults. If there are no faults, the LED remains switched off. It also lights up
when accessory configuration is being scanned.
• The yellow LED functions as a fault reset LED, and also indicates that a compressor timer is running
when it flashes.
In all the accessories:
• The green LED indicates whether there is communication and if it is correctly identified.
– If the LED remains lit, it indicates that the accessory is electrically powered but it has not been
correctly identified or it is not receiving the communications.
• The yellow LED:
– In the economiser accessory, it indicates that the outdoor air is favourable (LED lit up). The button
and the potentiometer store the renewal minimum.
– In the hot water coil accessory, it indicates that the water temperature is favourable (LED lit up)
or if the antifreeze function is being performed in the coil (LED flashing).
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