Daikin SUPER MULTI NX G Series, Service Manual

Page: 59 / 244

SiUS12-928_A Control Specification
Function and Control 50
3.6 Freeze-up Protection Control
Outline During cooling operation, the signals sent from the indoor unit allow the operating frequency
limitation and prevent freezing of the indoor heat exchanger. (The signal from the indoor unit is
divided into zones.)
Details
The operating frequency limitation is judged with the indoor heat exchanger temperature 2 seconds
after operation starts and 30 seconds after the number of operation room is changed.
3.7 Heating Peak-cut Control
Outline
During heating operation, the indoor heat exchanger temperature determines the frequency upper
limit to prevent abnormal high pressure.
Detail

The operating frequency is judged with the indoor heat exchanger temperature 2 minutes after
the operation starts and (
) seconds after the number of operation room is changed.

The maximum value of the indoor heat exchanger temperature controls the following (excluding
stopped rooms).
(R12295)
Ret u rn from stop
Reset zone
Indoor heat exchanger
thermistor temperat
u re
Up zone
Keep zone
Dropping zone
Stop zone
0°C (32°F)
3°C (37°F)
5°C (41°F)
7°C (45°F)
13°C (55°F)
(Reference)
Zone Control
Stop zone When the temperature reaches the stop zone, the compressor stops.
Dropping
zone The timer starts, and the frequency is
dropping
.
Keep zone The upper limit of frequency is kept.
Up zone The upper limit of frequency is increased.
Reset zone The upper limit of frequency is canceled.
18 class 24/32 class
65ºC (149ºF) 65ºC (149ºF)
50ºC (122ºF) 54ºC (129ºF)
48ºC (118ºF) 53ºC (127ºF)
47.5ºC (117.5ºF) 51ºC (124ºF)
46.5ºC (116ºF) 49ºC (120ºF)
(R11595)
Indoor heat exchanger
thermistor temperat u re
Stop zone
Dropping zone
Keep zone
Up zone
Reset zone
30
2
When increase
When decrease