Indoor Unit Fan Motor Over Temperature Protection; Compressor Temperature Protection; High Pressure Protection - Fujitsu AUXG36KRLB Service Manual

8-4. Indoor unit fan motor over temperature protection

When satisfy the following conditions, the protection works.
• After the 90 seconds from the fan operation, detect less than 300 rpm for 10 seconds.
• IPM trip protection works.
• Current overload protection works.
When detecting the above condtion, recheck the condition after 6 minutes. When count the twice,
the protection works.
• Protection contents
Reduce the static pressure 20 Pa. When it does not dissolve even the minimum static pressure
condition, work the following operation.
– Fan motor error displayed when less than 300 rpm for 10 seconds is detected after the 90 sec-
onds from the fan operation.
– Fan stop 40 seconds when IPM trip protection works.
– Fan stop 50 seconds when corrent overload protection works.

8-5. Compressor temperature protection

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

8-6. High pressure protection

Trigger condition
Release condition
8-7. Low outdoor temperature protection
When the outdoor temperature sensor detects lower than the trigger condition below, the compres-
sor is stopped.
Operation mode
Trigger condition
Release condition
8-4. Indoor unit fan motor over temperature protection
(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
Cooling/Dry
- (04-32) -
108°C
80°C
Heating
-20°C
-15°C
8. Various protections