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7.4   Protection 
7.4.1  3 minutes delay at restart for compressor. 
7.4.2 Sensor protection at open circuit and breaking disconnection 
7.4.3  Fan Speed is out of control. When Indoor Fan Speed is too high(higher than High Fan+300RPM)or 
too low(lower than 400RPM), the unit stops and LED displays failure information and can’t returns to 
normal operation automatically. 
7.4.4  Cross Zero signal error warning. If there is no Cross Zero signals in 4 minutes, the unit stops and LED 
displays failure information and can’t returns to normal operation automatically. 
7.4.5  The current protection of the compressor 
  Condition  Indoor fan  Compressor  Outdoor fan  Remark 
I< I
RESTORE
  On On On  
On   On   Off  Heating mode I
RESTORE
 <I< I
FAN
 
Low speed  On   On   Cooling mode 
I
FAN
 <I<I
5MIN
    Off  Off  After 5 Minutes   
Current up 
I
5MIN
<I< I
3SEC
    Off  Off  After 3 Seconds   
I
5MIN
<I< I
3SEC
    Off  Off  After 3 Seconds   
I
FAN
 <I<I
5MIN
    Off  Off  After 5 Minutes   
On   On   Off  Heating mode I
RESTORE
 <I< I
FAN
 
Low speed  On   On   Cooling mode 
Current down 
I< I
RESTORE
  On On On  
If compressor turns off for continuously 4 times due to current protection in 5 minutes from 
Compressor On, the unit stops and LED displays failure information and can’t returns to normal 
operation automatically. 
 
7.5   Fan-only mode 
Fan speed is high/mid/low/ Auto 
7.6   Cooling mode 
The 4-way valve is closed at cooling mode.   
The action of the compressor and the outdoor fan: 
 
Condition 
T=Indoor Temp. 
Ts=Setting Temp. 
Compressor Outdoor fan 
T> Ts+1  On  On Room temp. up 
T<Ts+1 Off Off 
T> Ts  On  On Room temp. down 
T<Ts Off Off 
Auto fan at cooling mode: 
 Condition 
T=Indoor Temp.-Setting Temp. 
Indoor fan speed 
T<4℃ Low 
4℃<T<5℃ Med. 
Room temp. up 
 
T>5℃ High 
T> 4℃ High 
1<T<℃ 4℃ Med. 
Room temp. down 
T<1℃ Low