Freeze-Up Protection Control; Heating Peak-Cut Control - Daikin CTXG09QVJUW Service Manual

SiUS121632EA
4.7

Freeze-up Protection Control

Outline During cooling operation, the signals sent from the indoor units control the operating frequency
limitation and prevent freezing of the indoor heat exchanger. (The signals from the indoor units are
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.
4.8

Heating Peak-cut Control

Outline During heating operation, the indoor heat exchanger temperature determines the frequency upper
limit to prevent abnormal high pressure.
Details
Functions and Control
(Reference)
13˚C (55.4˚F)
Reset zone
7˚C (44.6˚F)
Up zone
5˚C (41˚F)
Keep zone
3˚C (37.4˚F)
Dropping zone
0˚C (32˚F)
Stop zone
The operating frequency is judged with the indoor heat exchanger temperature 2 minutes after
the operation starts and
F
The maximum value of the indoor heat exchanger temperature controls the following (excluding
stopped rooms).
B
C
D
Indoor heat exchanger
temperature
A 65°C (149°F)
B 55°C (131°F)
C 54°C (129.2°F)
D 52°C (125.6°F)
E 50°C (122°F)
Zone
Stop zone When the temperature reaches the stop zone, the compressor stops.
Dropping zone The upper limit of frequency decreases.
Keep zone The upper limit of frequency is kept.
Up zone The upper limit of frequency increases.
Reset zone The upper limit of frequency is canceled.
Indoor heat exchanger
temperature (R2T)
seconds after the number of operation room is changed.
F (seconds)
When increase
When decrease
Control Specification
(R24042)
Stop zone
A
Dropping zone
Keep zone
Up zone
E
Reset zone
(R23928)
30
2
Control
87