Panasonic CS-RE9QKE Service Manual page 44

13.1.4 Compressor Overheating Prevention Control

Instructed frequency for compressor operation will be regulated by compressor discharge temperature. The
changes of frequency are as below.

If compressor discharge temperature exceeds 103°C, compressor will be stopped, occurs 4 times per 20 minutes,
timer LED will be blinking. ("F97" is indicated.)
13.1.5 Low Pressure Prevention Control (Gas Leakage Detection)

Control start conditions
For 5 minutes, the compressor continuously operates and outdoor total current is between 1.22A and 1.38A.
o
During Cooling and Soft Dry operations:
o
Indoor suction temperature - indoor piping temperature is below 4°C.
During Heating operations :
o
Indoor piping temperature - indoor suction is under 5°C.

Control contents
Compressor stops (and restart after 3 minutes).
o
If the conditions above happen 2 times within 20 minutes, the unit will:
o
 Stop operation
 Timer LED blinks and "F91" indicated.
13.1.6 Low Frequency Protection Control 1

When the compressor operate at frequency lower than 24 Hz continued for 20 minutes, the operation frequency
will be changed to 23 Hz for 2 minutes.
13.1.7 Low Frequency Protection Control 2

When all the below conditions comply, the compressor frequency will change to lower frequency.
Indoor intake air (°C)
Outdoor air (°C)
Indoor heat exchanger (°C)
Frequency
103°C
99°C
96°C
Comp temp
Temperature, T, for:
OFF
8Hz/45s Down
min A Hz
max B Hz
Free
Cooling/Soft Dry
T < 14 or T ≥ 30
T < 13 or T ≥ 38
T < 30
44
88°C
87°C
86°C
Heating
T < 14 or T ≥ 28
T < 4 or T ≥ 24
T ≥ 0