Fujitsu AS*G09KXCA Series Service Instruction page 24

4. COOLING PRESSURE OVERRISE PROTECTION
When the outdoor unit heat exchange sensor temperature rises to 65°C or greater the compressor is
stopped.The compressor restarst after the 140 sec, erapsed (ST). and the temperature detection starts
60 sec. erapsed after compressor started.
5. HIGH TEMPERATURE AND HIGH PRESSURE RELEASE CONTROL ( HEATING MODE )
On heating mode, the compressor frequency is controlled as following based on the detection value of the indoor
heat exchanger temperature sensor.
[ Control System ]
Indoor heat exchange
temperature rises
Compressor is stopped
63°C
The compressor frequency is
decreased 25rps every
120seconds.
55°C
The compressor frequency is
decreased 4rps every
120seconds.
53°C
It returns to the normal operation
6. HIGH PRESSURE PROTECTION
When the pressure switch becomes OFF (Open : higher than 4.2 MPa),
the compressor is stopped.
It is released when the pressure switch becomes ON (Close : lower than 3.2 MPa)
after 140sec. of compressor stop.
7. 4 way valve protection
The 4 way valve protection operates with the following conditions.
1. When the compresspr operates for more than 20 minutes.
2. Tn (Indoor unit HEX temp) -Tb (Room temp) > 10 deg in COOL and DRY
3. Tn (Indoor unit HEX temp) -Tb (Room temp) < -10 deg in HEAT
When the above condition 1&2 or 1&3 repeat 2 times for 2 min, the compressor stops.
When the same condition repeats 5 times, the system indicates the Error code.
8. Dew water protection (Operating in COOL, DRY)
When the vertical louver is set the position 5 ~ 8, and when the operating time erapsed 30 minutes,
the louver position changes automatically to the position 4.
9. EEV shutoff protection (Operating in HEAT)
The EEV shutoff protection operates with the following conditions.
1. When the compresspr operates for more than 20 minutes.
2. Tn (Indoor unit HEX temp) -Tb (Room temp) < 4 deg
When the above condition 1 and 2 repeat 2 times in 2 min, the compressor stops.
After the ST (Restart protection), the compressor starts.
Indoor heat exchange
temperature drops
Stable zone
50°C
01-20