Panasonic CS-E7JKEW, Service Manual

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14.1.5. 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 110
°
C, compressor will be stopped, occurs 4 times per 20 minutes, timer LED will
be blinking. (“F97” is indicated.)
14.1.6. Low Pressure Prevention Control (Gas Leakage Detection)
a. Control start conditions
• For 5 minutes, the compressor continuously operates and outdoor total current is between 0.65A and 1.65A.
• 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
- Timer LED blinks and “F91” indicated.
14.1.7. 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.
14.1.8. Low Frequency Protection Control 2
• When all the below conditions comply, the compressor frequency will change to lower frequency.
Temperature, T, for: Cooling/Soft Dry Heating
Indoor intake air (
°
C) T < 15 or T 30
—
Outdoor air (
°
C) T < 16 or T 38 T < 4 or T 24
Indoor heat exchanger (
°
C) T < 30 T 0