38
(1) Start conditions
A. When all of the following conditions are satisfied, defrosting will start. However, when the bypass valve turns OFF,
defrosting starts 10 minutes later.
(a) More than seven minutes have passed since the compressor start-up.
(b) The outdoor coil thermistor reads -5°C or below.
(c) The outdoor fan motor output step is 100%
(d) Total time of compressor operation exceeds 30 minutes, and the outdoor coil temperature has fallen by 8 degrees or
more in comparison with that of 10 minutes after the compressor start-up.
NOTE: The outdoor coil temperature of 10 minutes after the compressor start-up is memorized until the defrosting
operation has ended.
B. When all of the following conditions are satisfied, defrosting will start.
(a) ~ (c) The same as above (a) ~ (c) in item A
(d) Total time of compressor operation exceeds “defrost interval”.
Further information on the defrost interval is described in (3).
C. After the total time of compressor operation exceeds the defrost interval, the thermostat repeats ON/OFF three times.
Two minutes after the fourth “ON” of the thermostat, if the outdoor coil thermistor reads -5°C or below and the fan out-
put is 100%, defrosting will start.
NOTE: The count of the thermostat ON/OFF is cleared by the compressor-OFF command or defrosting start-up.
(2) During defrosting
●
Even if the thermostat turns OFF, defrosting continues.
●
The 4-way valve, bypass valve, outdoor fan, and indoor fan are OFF.
ON
Outdoor fan
Compressor
4-way valve
Bypass valve
Auto vane
Indoor fan
35degrees(SW5-3 OFF)or 20degrees(SW5-3:ON)discharge direction
(Remote controller still displays set direction.)
Outdoor unit
Indoor unit
ON
Set direction
ON
OFF
OFF
OFF
ON
OFF
ON
OFF
ON
OFF
Set direction
Defrosting
starts.
Defrosting
stops.
3-5 Defrosting in HEAT mode
<Defrosting time chart>
