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ESI Outdoor Unit Installation Instruction
05.2018
Manufacturer reserves the right to change at any time for specifications or designs without notice and incurring obligations.
Display
Communication fault between main
chip and INV drive chip
YES
Replace the main control board
NO
External factor other than
malfunction(e.g. noise interference).
1.Error definition and method to check:
Communication fault between the main control chip and inverter chip.
2.Possible causes:
Loose connection at CN21 terminal.
Damaged main control board
Turn off the power supply until the LED
display lights off. Unplug the cable from
terminal CN21, Restart power to check if
the fault remains.
CN21