Fujitsu AS*A09LKC Service Instructions Manual page 18

Defrost Flow Chart
The defrosting shall proceed by the integrating operation time
and outdoor heat exchanger temperature as follows.
Heating operation start : Compressor ON
Compressor integrating
operation:
Over 25 minutes to
below 240 minutes
Outdoor heat exchanger
temperature:
Below - 6°C
Outdoor heat exchanger temperature:
Over 16°C or
Compressor ON time: Over 15 minutes
(Not defrosted for 10 minutes)
Compressor integrating
operation:
Over 240 minutes
Outdoor heat exchanger
temperature:
Below - 3°C
Defrost start
Defrost Indicator:
[Operation lamp]
7 sec ON / 2 sec OFF
Compressor OFF
Outdoor fan motor OFF
30 sec later 4 - way valve OFF
36 sec later compressor ON
Defrost end
01-15