Fujitsu AB*30LBAG series Service Instruction page 36

3. ANTI-FREEZING CONTROL (Cooling mode)
The compressor frequency decreases on cooling mode when the indoor heat exchanger
temperature sensor detects the temperature lower than
Then, the anti-freezing control is released when it becomes higher than
(Fig.11 : Anti-freezing Protection Operation / Release Temperature)
Indoor heat exchange
temperature
3°C
6°C
12°C
When the compressor frequency becomes lower than minimum frequency,
the compressor operates at minimum frequency.
If the indoor heat exchanger temperature sensor detects the temperature lower than
3°C after 2minutes upon operating the compressor at minimum frequency,
the compressor stops.
4. COOLING PRESSURE OVER RISE PROTECTION
When the outdoor unit heat exchange sensor temperature rises to
the compressor is stopped and error display is indicated.
5. HIGH TEMPERATURE 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.
(Fig.12 : Heating Overload Protection Control)
Indoor heat exchange
temperature
63°C
54°C
50°C
The compressor frequency is
decreased 10Hz every 120seconds.
Hold
Compressor OFF : Hold
Compressor ON : Release of protection
Release of protection
Compressor is OFF
The compressor frequency is
decreased 10Hz every 60seconds.
Hold
Compressor OFF :
Release of protection
Compressor ON :
The compressor frequency is
increased 10Hz every 60seconds.
05-18
3°C.
6°C.
or greater,
70.5°C