15. Electronic Function 
15.1 Abbreviation 
T1: Indoor room temperature 
T2: Coil temperature of indoor heat exchanger 
middle. 
T2B: Coil temperature of indoor heat exchanger 
outlet. 
T3: Coil temperature of condenser 
T4: Outdoor ambient temperature 
T5: Compressor discharge temperature 
Td: Target temperature 
15.2 Display function 
15.2.1 Icon explanation on indoor display board 
(A5 Duct) 
15.2.2 Icon explanation on indoor display board 
(Compact cassette). 
 
15.2.3 Icon explanation on indoor display board 
(slim Cassette). 
 
 
15.2.1 Icon explanation on indoor display board 
(Ceiling Floor) 
 
 
15.3 Main Protection 
15.3.1  Three  minutes  delay  at  restart  for 
compressor 
1 minute delay for the 1
st
 time stand-up and 3 
minutes delay for others. 
15.3.2  Temperature  protection  of 
compressor top 
The unit will stop working when the compressor 
top temp. protector cut off, and will restart after 
the compressor top temp. protector restart. 
15.3.3  Temperature  protection  of 
compressor discharge 
When  the  compressor  discharge  temp.  is 
getting  higher,  the  running  frequency  will  be 
limited as below rules: 
---Compressor  discharge  temp.  T5>115 ℃
(239°F) for 5s, compressor stops and restarts 
up till T5<90℃(194°F) 
---110<T5<115 ℃ (239°F),  decrease  the 
frequency to the lower level every 2 minutes. 
---105(221°F)<T5<110℃(230°F),  keep  running 
at the current frequency. 
----T5<105℃(221°F), no limit for frequency. 
15.3.4 Fan speed malfunction 
When indoor  fan  speed keeps  too  low  (lower 
than 300RPM) for 50s, the indoor fan will shut 
off and restart 30s later, if protection happened 
3 times when fan motor restarts continuously, 
the unit will stop and the LED will display the 
failure. 
When outdoor fan speed keeps too low (lower 
than  100RPM)  or  too  high  (higher  than 
1500RPM) for  60s,  the  unit  will  stop  and  the 
LED  will  display  the  failure.  Malfunction  is 
cleared 30s later. 
OPERATION
TIMER
DEF./FAN
ALARM
Temporary button
Operation lamp
Timer indicator
Infrared signal receiver
Alarm indicator
PRE-DEF indicator(cooling and heating type)
or fan only indicator(cooling only type)
MANUAL
Display digital tube