Daikin VRV IV+ Service Manual page 117

2.3.103 L4-09-10-11 – Inverter PCB A6P high fin temperature
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05
DANGER: RISK OF ELECTROCUTION
Confirm the rectifier voltage is below 10 V DC before proceeding, see
rectifier voltage" [
2 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.
3 Check if heat sink plate is correctly fixed with screws.
Possible cause: Heat sink plate not correctly installed.
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 A7P. See
4
PCB" [ 259].
Possible cause: Faulty fan inverter PCB A7P.
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.
4
356].
"3.7 Expansion
Sub error code
09
10
11
2 Troubleshooting
|
"To check the
4
valve" [ 244].
"3.7 Expansion
"3.8 Fan inverter
Unit
Main
Sub 1
Sub 2
Service manual
117