Si04-115
General Functionality
Main Function
35
1.14
Freeze Protection Function in Cooling
Outline
During Cooling/Dry operation, when the heat exchanger’s temperature falls down excessively,
the capacity supply will be reduced (frequency step down) so as to prevent freeze of the heat
exchanger and the creation of dew on a rotor caused by a excessive capacity supply to the
indoor unit.
Processing
∗
DTO : Freeze protection temperature of heat exchanger
"
The restriction for frequency is not conducted in the return area by means of freeze
protection control.
"
Frequency is increased approximately every 2 Hz/min. in the up-area.
"
Frequency alteration in the steady area is not conducted.
"
Frequency - down is carried out in the step down area approximately every 2 ~ 4 Hz/min..
"
Compressors stop in the stop area. After compressor stops, fan keeps operating in 800 rpm
(LL tap), aiming at rising heat exchanger’s temperature.
Setting a constant
J type
DTO4
15°C
DTO3
8°C
DTO2
7°C
DTO1
5°C
DTO0
0°C
Return
at the descend of
heat exchanger temp.
at the rise of heat exchanger temp.
Return from stop.
DTO0
DTO1
DTO2
DTO3
DTO4
Step down area
Steady area
Stop area
Up-area
(R1920)
