Panasonic CU-2TZ41TBE Service Manual page 41

Diagnosis Abnormality or
display protection control
Indoor standby units
F17
freezing abnormality
Power factor correction
F90
(PFC) circuit protection
Refrigerant cycle
F91
abnormality
Compressor abnormal
F93
revolution
Compressor discharge
F94 pressure overshoot
protection
Outdoor cooling high
F95
pressure protection
Power transistor module
F96
overheating protection
Compressor overheating
F97
protection
Total running current
F98
protection
Outdoor direct current
F99
(DC) peak detection
Abnormality judgment Protection operation
3 times happen within
40 minutes
4 times happen within
20 minutes
4 times happen within
60 minutes
4 times happen within
20 minutes
4 times happen within
20 minutes
4 occurrences within
20 minutes
4 times happen within
30 minutes
3 times happen within
30 minutes
3 times happen within
20 minutes
Continuous happen for
7 times
Problem
Wrong wiring and
connecting pipe,
-
expansion valve
leakage
Power factor
- correction circuit
abnormal
Refrigeration cycle
-
abnormal
Compressor abnormal
-
evolution
Compressor discharge
-
pressure overshoot
Cooling high pressure
-
protection
Power transistor
-
module overheat
- Compressor overheat 
Total current
-
protection
Power transistor
- module current
protection
41
Check location

Check indoor/outdoor
connection wire and pipe

Indoor heat exchanger
sensor lead wire and
connector

Expansion valve lead
wire and connector

Outdoor PCB faulty

Insufficient refrigerant or
valve close

Power transistor module
faulty or compressor lock

Check refrigeration
system

Check refrigeration
system

Outdoor air circuit

PCB faulty

Outdoor air circuit (fan
motor)
Insufficient refrigerant

Check refrigeration
system

Power source or
compressor lock

Power transistor module
faulty or compressor lock