Fujitsu ARTG36LHTB Service Manual page 130

3. Defrost Flow Chart
The defrosting shall proceed by the integrating operation time, outdoor temperature
and outdoor heat exchanger temperature as follows.
1st defrost
Compressor Compressor
integrating integrating
operation: operation:
Over 22 min. Over 62 min.
Outdoor Outdoor
heat exchanger heat exchanger
temperature: temperature:
Below - 9°C Below - 5°C
Heating operation start : Compressor ON
2nd and later defrost
Compressor
integrating
operation:
Over 35 min.
Tn-Tn10 < - 5deg
Tn-Tnb < - 2deg
However, Tn <- 6°C
=
Defrost start
Defrost Indicator:
[Operation lamp]
7 sec ON / 2 sec OFF
Outdoor heat exchanger temperature:
Over +13°C
or
Compressor ON time: Maximum 15 minutes
Defrost end
01-16
(Not defrosted for 10 minutes)
Compressor
OFF count :
40 times
(Less than 10min.)
Integrating defrost
(Constant monitoring)
Compressor Compressor
integrating integrating
operation: operation:
Over 240 min. Over 215 min.
Outdoor Outdoor
heat exchanger heat exchanger
temperature: temperature:
Below - 3°C Below - 5°C