U4-00 - Indoor/Outdoor Unit Communication Problem - Daikin Sky Air Advance RZA200D7Y1B Service Manual

2.4.30 U4-00 – Indoor/outdoor unit communication problem
RZA200+250D7Y1B
Sky Air Advance-series
ESIE19-13A – 2020.05
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
Trigger
Communication failure
between outdoor and
indoor unit.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1 Check if the power supply is conform with the regulations. See
circuit" [ 4 135].
Possible cause:
▪ Faulty or disturbance of the power supply (imbalance >10%),
▪ Power drop,
▪ Short circuit.
2 Perform a check of the power supply, connections, wiring,... between the
outdoor unit and the indoor unit. See
Possible cause: Faulty wiring between the outdoor unit and the indoor unit.
3 Perform a check of the main PCB. See
Possible cause: Faulty main PCB.
4 Perform a check of the outdoor unit fan motor. See
4
motor" [ 107].
Possible cause: Faulty outdoor unit fan motor.
5 Check that "standby electricity saving mode" is OFF. See installation manual.
Possible cause: "Standby electricity saving mode" is ON, while this mode is
ONLY compatible with Split indoor units.
Prerequisite: Stop the unit operation via the user interface.
6 Turn OFF the respective circuit breaker.
DANGER: RISK OF ELECTROCUTION
Confirm the rectifier voltage is below 10 V DC before proceeding, see
rectifier voltage" [
7 Check that the thermal interface grease is applied properly on the (PCB or
refrigerant piping) contact surface of the heat sink. Adjust if needed.
Possible cause: Thermal interface grease NOT applied properly on the heat
sink.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
Effect
Unit will stop operating.
"4.1 Electrical
"3.9 Main
4
135].
2 Troubleshooting
|
Reset
Automatic reset.
"4.1 Electrical
4
circuit" [ 135].
4
PCB" [ 95].
"3.11 Outdoor unit fan
"To check the
Service manual
39