Various Protections - Fujitsu AO G24LBCB Series Service Instruction

1-24. VARI O US PROTECTI O NS
1. DI S CHARGE GAS TEMPERATURE OVERRI S E PREVENTI O N CONTROL
The discharge gas thermosensor (discharge thermistor : Outdoor side) will detect discharge gas
temperature.
When the discharge temperature becomes higher than Temperature ,the compressor frequency
is decreased 20rps, and it continues to decrease the frequency for 20rps every 120 seconds until
the temperature becomes lower than Temperature .
When the discharge temperature becomes lower than Temperature , the control of
the compressor frequency is released.
When the discharge temperature becomes higher than Temperature
and the indoor unit LED starts blinking.
(Table14 : Discharge Temperature Over Rise Prevention Control / Release Temperature)
Temperature
104°C
2. CURRENT RELEASE CONTROL
The compressor frequency is controlled so that the outdoor unit input current does not exceeds
the current limit value that was set up with the outdoor temperature.
The compressor frequency returns to the designated frequency of the indoor unit at the time
when the frequency becomes lower than the release value.
( Table 15 : Current release operation value / release value )
Model 24
[ Heating ]
OT (Control / Release)
10.5A / 10.0A
17°C
10.5A / 10.0A
12°C
13.5A / 13.0A
5 °C
14.5A / 14.0A
OT : Outdoor Temperature
3. ANTI F REEZI N G CONTROL (Cooling and Dry mode)
The compressor frequency is decrease on cooling & dry mode when the indoor heat exchanger
temperature sensor detects the temperature lower than Temperature .
Then, the anti-freezing control is released when it becomes higher than Temperature .
(Table 16 : Anti-freezing Protection Operation / Release Temperature)
Outdoor temperature
Over than 10°C
or 12°C
Less than 10°C
or 12°C
Temperature Temperature
101°C
[ Cooling ]
OT (Control / Release)
50°C
46°C
40°C
OT : Outdoor Temperature
Temperature
*1
*2
4°C
*1
*2
*1. When the temperature rises.
*2. When the temperature drops.
110°C
7.0A / 6.5A
7.0A / 6.5A
9.5A / 9.0A
13.5A / 13.0A
Temperature
7°C
13°C
01-23
,the compressor is stopped