Current Release Control; Compressor Temperature Protection; High Pressure Protection - Fujitsu ASUH18LMAS Service Manual

8-3. Current release control

The rotation number of compressor is controlled so that the outdoor unit input current does not ex-
ceeds current limit value set according to the outdoor temperature.
The rotation number of compressor returns according to the operation mode, when the current be-
comes lower than the release value.
¢ AOUH18LMAS1
Operation mode
Cooling
Heating
¢ AOUH24LMAS1
Operation mode
Cooling
Heating

8-4. Compressor temperature protection

→hen the compressor temperature sensor detects higher than the trigger condition below, the com-
pressor is stopped. →hen the compressor temperature sensor detects the release condition, the pro-
tection is released.
Trigger condition
Release condition

8-5. High pressure protection

Trigger condition
Release condition
8-3. Current release control
Outdoor temp. (Ta)
125.6 °F (52 °C) ≤ Ta
122.0 °F (50 °C) ≤ Ta < 125.6 °F (52 °C)
Ta < 122.0 °F (50 °C)
60.8 °F (16 °C) ≤ Ta
53.6 °F (12 °C) ≤ Ta < 60.8 °F (16 °C)
Ta < 53.6 °F (12 °C)
Outdoor temp. (Ta)
125.6 °F (52 °C) ≤ Ta
122.0 °F (50 °C) ≤ Ta < 125.6 °F (52 °C)
114.8 °F (46 °C) ≤ Ta < 122.0 °F (50 °C)
107.6 °F (42 °C) ≤ Ta < 114.8 °F (46 °C)
Ta < 107.6 °F (42 °C)
68.0 °F (20 °C) ≤ Ta
60.8 °F (16 °C) ≤ Ta < 68.0 °F (20 °C)
Ta < 60.8 °F (16 °C)
- (04-32) -
Trigger condition
8.0 A
10.0 A
12.5 A
10.0 A
11.5 A
13.0 A
Trigger condition
8.0 A
10.0 A
13.0 A
14.0 A
14.5 A
11.0 A
13.0 A
15.0 A
226.4°F (108°C)
176.0°F (80°C)
(3 minutes after compressor stop)
Pressure switch: Off (Open: Higher than 4.2 MPa)
Compressor stop
Pressure switch: On (Close: Lower than 3.2 MPa)
(3 minutes after compressor stop)
Compressor restart
Release condition
7.5 A
9.5 A
12.0 A
9.5 A
11.0 A
12.5 A
Release condition
7.5 A
9.5 A
12.5 A
13.5 A
14.0 A
10.5 A
12.5 A
14.5 A
8. Various protections