Service manual

27
YES
YES
YES
YES
YES
YES
YES
4)DEFROSTING OPERATION (Heating)
•When the capacity of the unit has been decreesed due to frosting up of the outdoor heat exchanger during
heating, the temperature drop gradient is detected by the microcomputer-controlled temperature sensing
system, and defrosting operation is started.
DEFROSTING FLOWCHART
Compressor ON
Integrated operating time of
compressor is longer than
3 hours
Integrated operating time of
compressor is longer than
1.5 hours
Thermo OFF
(Compressor OFF)
Temperature of indoor heat
exchanger coil is lower than
53°C.
Thermo ON
(Compressor ON)
Defrosting thermo in the
outdoor unit is OFF.
(Below 4°C)
Defrosting begins.
Cold-draft prevention.
Release of defrosting.
Temperature of outdoor heat
exchange coil is higher than
12°C.
Defrosting time is over
11.5 minutes.
Temperature of indoor heat
exchanger coil is lower than
45°C
Temperature in indoor heat
exchanger coil drops 0.8
deg/6 min. or more and
repeats 3 times continuously.
Integrated operating time of
compressor is more than
20 minutes.
Compressor keeps running
for 5 minutes
A B C
NO