18 Troubleshooting
Installation and operation manual
45
LREN8~12A7 + LRNUN5A7
CO
₂
ZEAS outdoor unit and capacity up unit
4P704141-1B – 2022.12
Main code
LREN*
LRNUN5*
Cause
Solution
O
O
▪ Heat exchanger of outdoor unit is blocked.
▪ The outdoor temperature is above the
maximum operating temperature.
▪ Check if any obstacles block the heat
exchanger and remove them.
▪ Operate the unit only within the temperature
operation range.
O
O
Supply voltage dropped.
▪ Check the power supply.
▪ Check the wiring size and length of the
power supply. They must be according to the
specifications.
O
O
Transmission outdoor unit – inverter: INV1/
FAN1 transmission trouble
Check connection.
O
O
Unbalanced power supply voltage
Check the power supply.
O
O
Lost phase in power supply
Check the connection of the power supply
cable.
O
O
Insufficient supply voltage
Check the power supply.
—
O
Communication error between the capacity
up unit and the outdoor unit.
Check the connection of the communication
cables upstream between the capacity up unit
and outdoor unit. (Error displayed on the
capacity up unit.)
O
—
Communication error between the capacity
up unit and the outdoor unit.
Check the connection of the communication
cables upstream between the capacity up unit
and outdoor unit. (Error displayed on the
outdoor unit.)
O
—
Refrigerant leaking
Check the refrigerant amount
O
—
Refrigerant over charging
Check the refrigerant amount
NOTICE
After turning ON the operation switch, wait at least
1 minute before turning OFF the power supply. Electrical
leakage detection is performed shortly after the
compressor starts. Turning off the power supply during this
check will result in an incorrect detection.
