Fujitsu AOYG45LAT8 User Manual page 36

1-19. OFF DEFROST OPERATION CONTROL
When operation stops in the [Heating operation] mode, if frost is adhered to the outdoor unit heat
exchanger, the defrost operation will proceed automatically. In this time, the outdoor unit will allow
the heat exchanger to defrost, and then stop.
1. OFF DEFROST OPERATION CONDITION
When heating operation stops, all of following conditions are met, OFF defrost operation starts.
1. Compressor operation integrating time lasts for more than 30 minutes.
2. Compressor countinuous operation time lasts for more than 10 minutes.
3. Outdoor unit heat exchenger temperature is less than -4°C.
If the operation stops in defrost operation, defrost operation is kept untill the it is completed.
2. OFF DEFROST RELEASE CONDITION
OFF defrost operation is released when the conditions becomes as shown in Table 31
( Table 20 : OFF Defrost Release Condition )
Outdoor heat exchanger temperature is higher than 12°C
Compressor operation time has passed 15 minutes.
OFF Defrost Flow Chart
Compressor integrating operation : Over 30 minutes
Compressor countinuous operation time : Over 10 minutes
Outdoor heat exchanger temperature : Below -4°C
Release Condition
or
Heating operation stop
and
and
Defrost start
Outdoor heat exchanger temperature : Over 12°C
or
Compressor ON time : Maximum 15 minutes
Defrost end
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