Daikin VRV IV+ Service Manual page 160

2 | Troubleshooting
2.3.155 U4-01 – Transmission error between indoor units and outdoor unit
Service manual
160
2 Check the F1‑F2 transmission line between the indoor units and outdoor unit.
See "4.1 Electrical
Possible cause: Faulty or interruption in transmission line between indoor
units and outdoor unit.
3 Perform a test run from the outdoor unit. See installer reference guide for
more information.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
Trigger
Main PCB detects
abnormal transmission on
F1-F2 transmission line to
indoor units.
Transmission between
indoor units and outdoor
unit is interrupted while in
initialization.
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
4
circuit" [ 356].
Possible cause:
▪ Faulty or disturbance of the power supply (imbalance >10%),
▪ Power drop,
▪ Short circuit.
2 Check the F1‑F2 transmission line between the indoor units and outdoor unit.
See "4.1 Electrical
Possible cause: Faulty or interruption in transmission line between indoor
units and outdoor unit.
3 Check field setting 1‑10 to count the indoor units, see
4
settings" [ 455]. If less indoor units detected than it should be, check the
indoor unit(s) that have power black‑out or malfunctioning PCB. See service
manual of the respective indoor unit for more information.
Possible cause: Power black‑out or malfunctioning PCB on indoor unit(s).
4 Perform a check of the main PCB. See
Possible cause: Faulty main PCB.
5 Perform a power reset. If the error disappears and is raised again after a
while, check for the presence of an external source causing electrical noise.
See "4.3 External factors" [
Possible cause: External source may cause interference.
4
circuit" [ 356].
Effect
Unit will stop operating.
4
circuit" [ 356].
"3.11 Main
4
372].
Reset
Auto reset.
"4.1 Electrical
"6.9 Field
4
PCB" [ 290].
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05