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5.  Electronic Function 
5.1 Abbreviation 
T1:  Indoor ambient temperature 
T2:  Middle indoor heat exchanger coil 
temperature 
T2B: Indoor heat exchanger exhaust coil 
temperature (located on the outdoor unit) 
T3:  Outdoor heat exchanger pipe temperature 
T4:  Outdoor ambient temperature 
T5: Compressor discharge temperature 
5.2 Electric Control Working Environment. 
5.2.1 Input voltage: 230V. 
5.2.2 Input power frequency: 60Hz. 
5.2.3 Indoor fan standard working amp.: <1A 
5.2.4 Outdoor fan standard working amp.: <1.5A. 
5.2.5 Four-way valve standard amp.: <1A. 
 5.3 Main Protection 
5.3.1 Compressor Restart Delay 
---- The compressor takes 1 minute to start up the 
first time. Further restarts take 3 minutes. 
5.3.2  Temperature  Protection  of  Compressor 
Discharge. 
When  the  discharge  temperature  of  the 
compressor rises, the running frequency is limited 
according to the following rules: 
----If  105 ℃   (221  ℉ ) ≦ T5<110 ℃   (230  ℉ ), 
maintain the current frequency. 
----If  the  temperature  increase  and  T5≧110℃ 
(230 ℉), decrease the frequency to a lower level 
every 2 minutes till to F1. 
---If  T5≧ 115℃   (239  ℉ )  for  10  seconds,  the 
compressor stops and then restart untill T5<90℃ 
(194 ℉). 
5.3.3 Fan Speed Malfunction 
---- If outdoor fan speed is lower than 100RPM or 
higher  than  2400RPM  for  60  seconds  or  more, 
the unit stops and LED displays E8 failure code. 
5.3.4 Inverter Module Protection. 
----  The  inverter  protection module  ensures  that 
faults related to current, voltage, or temperature 
does not damage the inverter. 
If  these  protections  are  triggered,  the  A/C  unit 
stops and the LED displays the failure code. 
The  unit  restarts  3  minutes  after  the  protection 
mechanism has turned off. 
 
5.3.5 Low Voltage Protection 
V O L T A G E
N o  lim it
V O L T _ L T M _ F R E Q 1 _ A D D
V O L T _ L T M _ F R E Q 2 _ A D D
 
Note: If low voltage protection triggers and 
voltage is not restored to normal within 3 
minutes, the protection remains active even 
after a machine restart. 
5.3.6 Compressor Current Limit Protection 
The temperature interval for the current limit is 
the same as the range of the T4 frequency limit. 
Cooling mode: