Daikin VRV IV+ Service Manual page 154

2 | Troubleshooting
2.3.147 U2-24-27-30 – Inverter circuit power supply abnormality - inverter PCB A6P DC circuit not
charging
Service manual
154
Trigger
Inverter PCB A6P detects
DC voltage cannot reach
or maintain minimum
500 V DC.
No zero cross is detected
by main PCB through at
least 10 seconds.
Abnormal voltage drop is
detected by DC voltage
detection circuit.
Abnormal voltage rise is
detected by over voltage
detection circuit.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1 Check if the power supply wiring is correct. See
Possible cause: Incorrect power supply wiring.
2 Perform a check of the noise filter PCB A5P. See
4
PCB" [ 298].
Possible cause: Faulty noise filter PCB A5P.
3 Perform a check of the inverter PCB A6P. See
Possible cause: Faulty inverter PCB A6P.
4 Check the wiring between the PCB's. See
Possible cause: Faulty wiring between PCB's.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
Main error code
U2
INFORMATION
Main, Sub 1 and Sub 2 indications are relevant in multiple outdoor unit
configurations. Main outdoor unit is the unit to which F1‑F2 IN transmission line is
connected. Main, Sub 1 and Sub 2 outdoor units can be identified by field setting
1‑00.
Effect
Unit will stop operating.
"3.10 Inverter
"6.2 Wiring
Sub error code
24
27
30
Reset
Power reset at outdoor
unit.
4
"4.1 Electrical circuit" [
"3.12 Noise filter
4
PCB" [ 274].
4
diagram" [ 385].
Unit
Main
Sub 1
Sub 2
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05
356].