119 
 
16.1.5  Low Pressure Prevention Control (Gas Leakage Detection) 
  Control start conditions 
o  For 5 minutes, the compressor continuously operates and outdoor total current is between 0.29A and 0.44A 
(TZ20/25/35/42ZK, RZ25/35ZK) 0.36A and 0.54A (TZ50/60/71ZK, RZ50ZK). 
o  During Cooling and Soft Dry operations: 
Indoor suction temperature - indoor piping temperature is below 4°C. 
o  During Heating operations : 
Indoor piping temperature - indoor suction is under 5°C. 
  Control contents 
o  Compressor stops (and restart after 3 minutes). 
o  If the conditions above happen 2 times within 20 minutes, the unit will: 
  Stop operation 
  Timer LED blinks and “F91” indicated. 
16.1.6 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. 
16.1.7 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 < 14 or T ≥ 30  T < 14 or T ≥ 28 
 Outdoor air (°C)  T < 13 or T ≥ 38  T < 4 or T ≥ 24 
 Indoor heat exchanger (°C)  T < 30  T ≥ 0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Compressor = OFF
Compressor Frequency
Reduce
Compressor Frequency
Limited
Free
Comp. temperature
103°C
99°C
96°C
88°C
87°C
86°C