Fujitsu AB F18LAT Series Service Instruction page 25

3. Defrost Flow Chart
The defrosting shall proceed by the integrating operation time
and outdoor heat exchanger emperature as follows.
(In case of 1st defrost)
Compressor integrating Compressor integrating
operation: operation:
Over 17 minutes to Over 62 minutes to
below 62 minutes below 240 minutes
Outdoor
heat exchanger
temperature:
Below - 9°C
Outdoor temp -
Outdoor heat exchanger
temperature:
Above 5 degC
Heating operation start : Compressor ON
Compressor integrating
operation:
Over 240 minutes
Outdoor Outdoor
heat exchanger heat exchanger
temperature: temperature:
Below - 5°C Below - 3°C
Defrost start
Defrost Indicator:
[Operation lamp]
7 sec ON / 2 sec OFF
Outdoor heat exchanger temperature: Over 10°C
Compressor ON time: Over 15 minutes
Defrost end
(Not defrosted for 10 minutes)
Compressor integrating
operation:
Over 35 minutes to
below 240 minutes
Outdoor fan : OFF
Compressor : OFF
EEV : 480pulse
4-way valve : OFF
Compressor : ON
(Frequency : 70Hz)
or
01-21
(In case of 2nd and later defrost)
Compressor integrating
operation:
Over 240 minutes
Outdoor Outdoor
heat exchanger heat exchanger
temperature: temperature:
Below - 6°C Below - 3°C