Brand : Daikin VRV4
model : FXMQ63PVE(indoor)/RXQ8AYM(outdoor)
error code : U4-01
Error code U4
System Comunication Fault.
This is a communication issue between the indoor and outdoor unit's.
This fault can be caused by the outdoor unit being powered down or a BS Box or fan coil
also bring powered down.
When any of these things happens it cause confusion in the communication protocol and stop everything communicating correctly. Please check and restore power to any equipment if this is the cause.
1)check all indoor unit power supply
2)check outdoor unit power supply.
3)On back if any switch trip and reset outdoor unit
4)If any indoor and outdoor part's incoming is okay, please check the pc board or communication wire
5)If pc board or communication wire is faulty, please replace it.
#Daikin #VRV4 #bonmj
