Panasonic CU-S18NKU-1 Air Conditioner User Manual


 
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12.4.2 S18NK, S22NK
Overheating Prevention Control
o When the IPM temperature rises to 212°F, compressor operation will stop immediately.
o Compressor operation restarts after 3 minutes the temperature decreases to 203°F.
DC Peak Current Control
o When electric current to IPM exceeds set value of 29.9A, the compressor will stop operate. Then, operation
will restart after 3 minutes.
o If the set value is exceeded again more than 30 seconds after the compressor starts, the operation will
restart after 2 minute.
o If the set value is exceeded again within 30 seconds after the compressor starts, the operation will restart
after 1 minute. If this condition repeats continuously for 7 times, all indoor and outdoor relays will be cut off.
12.5 Compressor Overheating Prevention Control (For S18, S22NK only)
Instructed frequency for compressor operation will be regulated by compressor discharge temperature. The
changes of frequency are as below.
If compressor discharge temperature exceeds 233.6°F, compressor will be stopped, occurs 4 times per 20
minutes, timer LED will be blinking. “F97” is indicated.
12.6 Low Pressure Protection Control (Gas Leakage Detection)
Control start conditions
o For 5 minutes, the compressor continously operates and outdoor total current is between 0.66A and 1.25A
(S9NK and S12NK) or 0.81A and 1.23A (S18NK and S22NK).
o During Cooling and Soft Dry operation:
Indoor suction temperature – indoor piping temperature is below 39.2°F
Control contents
o Compressor stops (and restart after 3 minutes).
o If the conditions above happened 2 times within 20 minutes, the unit will:
Stop operation
Timer LED blinks and “F91” indicated.
12.7 Low Frequency Protection Control 1
When the compressor operates at frequency lower than 26Hz continued for 20 minutes, the operation frequency
will be changed to 25Hz for 2 minutes. (For S9NK and S12NK)
When the compressor operates at frequency lower than 25Hz continued for 240 minutes, the operation frequency
will be change to 24Hz for 2 minutes. (For S18NK and S22NK)
12.8 Low Frequency Protection Control 2
When all below conditions comply, minimum limit of compressor frequency will be set.
Cooling / Soft Dry
Temperature, T, for:
S9NK and S12NK S18NK and S22NK
Indoor intake air (°F) T < 59 or T 86 T < 57.2 or 86
Outdoor air (°F) T < 60.8 or T 100.4 T < 55.4 or T 100.4
Indoor heat exchanger (°F) T < 86 T < 86