Daikin VRV IV+ Service Manual page 116

2 | Troubleshooting
2.3.102 L4-07-19-21 – Fan inverter PCB A7P high fin temperature
Service manual
116
4 Check (by touching) if refrigerant is flowing through the radiant cooling
refrigerant circuit. The radiant cooling refrigerant circuit should be warm if
refrigerant is flowing. If no refrigerant flow, perform a check of the liquid
cooling expansion valve, see
Possible cause: No refrigerant flow through the radiant cooling refrigerant
circuit.
5 Perform a check of the liquid cooling expansion valve. See
4
valve" [ 244].
Possible cause: Faulty liquid cooling expansion valve.
6 Check ambient temperature. Check if outdoor unit location temperature
differs drastically.
7 Check if there is discharge air by-pass on installation location.
Possible cause: External noise. Check further on how to eliminate external
factors.
8 Perform a check of the fan inverter PCB A4P. See
4
PCB" [ 259].
Possible cause: Faulty fan inverter PCB A4P.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
Main error code
L4
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.
Trigger
Thermistor located inside
the power module of the
fan inverter PCB detects a
temperature higher than
a certain value.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
Prerequisite: Stop the unit operation via the central controller.
1 Turn OFF the respective circuit breaker.
"3.7 Expansion valve" [
Sub error code
07
19
21
Effect
Unit will stop operating.
4
244].
"3.7 Expansion
"3.8 Fan inverter
Unit
Main
Sub 1
Sub 2
Reset
Manual reset via remote
controller.
Outdoor unit power reset.
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05