Panasonic CS-HZ9RKE-1 Service Manual page 74

15.1.4 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
will be blinking. ("F97" is indicated.)
15.1.5 Low Pressure Prevention Control (Gas Leakage Detection)
a. Control start conditions

For 5 minutes, the compressor continuously operates and outdoor total current is between 0.75A and 0.95A.

During Cooling and Soft Dry operations:
Indoor suction temperature - indoor piping temperature is below 4°C.

During Heating operations :
Indoor piping temperature - indoor suction is under 5°C.
b. Control contents

Compressor stops (and restart after 3 minutes).

If the conditions above happen 2 times within 20 minutes, the unit will:
Stop operation
o
Timer LED blinks and "F91" indicated.
o
15.1.6 Low Frequency Protection Control 1

When the compressor operate at frequency lower than 24 Hz continued for 240 minutes, the operation frequency
will be changed to 23 Hz for 2 minutes.
15.1.7 Low Frequency Protection Control 2
 When all the below conditions comply, the compressor frequency will change to lower frequency.
Indoor heat exchanger (°C)
103°C
99°C
96°C
Comp. Discharge temperature
Temperature, T, for:
Indoor intake air (°C)
Outdoor air (°C)
°
C, compressor will be stopped, occurs 4 times per 20 minutes, timer LED
Compressor = OFF
Compressor Frequency
Reduce
Compressor Frequency
Maintain
Free
Cooling / Soft Dry
T < 14 or T ≥ 30
T < 13 or T ≥ 38
T < 30
74
88°C
87°C
86°C
Heating
T < 14 or T ≥ 28
T < 4 or T ≥ 24
T < 0