Check SiAF332111E
348 Part 6 Service Diagnosis
6.9 Inverter-Related Error Codes
CHECK 9
Code Name Condition for determining error Major cause
Compressor
current L5
Instantaneous overcurrent
of compressor
• Inverter output current exceeds A
(A) even instantaneously.
• Liquid sealing
• Defective compressor
• Defective inverter PCB
L8
Overcurrent of
compressor (Electronic
superheating protection
sensor)
• Compressor overload running
A current of B (A) or more continues
for a period of consecutive 5
seconds or that of C (A) or more
continues for a period of
consecutive 260 seconds.
• The inverter loses synchronization.
• Back-flow of compressor liquid
• Sudden changes in loads
• Disconnected compressor wiring
• Defective inverter PCB
Protection
device and
others
E5
Compressor lock • The compressor is in the locked
status (does not rotate).
• Defective compressor
L1
Defective inverter PCB • No output is given. • Defective heavy current part of
compressor
L4
Radiation fin temperature
rise
• The radiation fin temperature
reaches D (°C) or more (while in
operation).
• Defective fan
• Running in overload for an extended
period of time
• Defective inverter PCB
L9
Defective startup of
compressor
• The compressor motor fails to start
up.
• Liquid sealing or defective
compressor
• Excessive oil or refrigerant
• Defective inverter PCB
LC
Transmission error
(between microcomputers
on the outdoor main PCB)
• No communications are carried
out across outdoor main PCB -
inverter PCB - fan PCB.
• Broken wire in communication line
• Defective outdoor main PCB
• Defective inverter PCB
• Defective fan PCB
P1
Imbalanced power supply • Power supply voltages get
significantly imbalanced among
three phases.
• Power supply error (imbalanced
voltages of 2% or more)
• Defective inverter PCB
• Dead inverter PCB
P4
Defective radiation fin
thermistor
• The radiation fin thermistor gets
short circuited or open.
• Defective radiation fin thermistor
PJ
PCB mismatching • Any PCB of specification different
from that of the product is
connected.
• PCB of different specification
mounted
U2
Power supply voltage
error
• The inverter power supply voltage
is high or low.
• Power supply error
• Defective inverter PCB
Model A (A) B (A) C (A) D (°C)
RXQ4AR 36.9 17.0 14.8 92
RXQ5AR 51.5 31.0 24.1 85
RXMQ10/12AR 59.1 33.5 27.6 87