SiUS091133
Control Specification
Function and Control
48
3.6
Freeze-up Protection Control
Outline
During cooling operation, the signal sent from the indoor unit controls the operating frequency
limitation and prevents freezing of the indoor heat exchanger. (The signal from the indoor unit is
divided into zones.)
Detail
The operating frequency limitation is judged with the indoor heat exchanger temperature.
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
A
B
C
FTXS09/12LVJU
9.5°C (49.1°F)
7.5°C (45.5°F)
5.5°C (41.9°F)
FTXS15/18/24/30/36LVJU, FDXS series
7°C (44.6°F)
5°C (41°F)
3°C (37.4°F)
(R16967)
Reset zone
Indoor heat exchanger
thermistor temperature
Up zone
Keep zone
Dropping zone
Stop zone
0˚C
(32˚F)
C
B
A
13˚C
(55.4˚F)
Zone
Control
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.
A
B
C
D
E
09 class
60°C (140°F)
56°C (132.8°F) 53°C (127.4°F) 51°C (123.8°F) 46°C (114.8°F)
12 class
60°C (140°F)
52°C (125.6°F)
50°C (122°F)
48°C (118.4°F) 43°C (109.4°F)
15/18 class
60°C (140°F)
57°C (134.6°F) 56°C (132.8°F) 54°C (129.2°F) 52°C (125.6°F)
24/30/36 class
65°C (149°F)
56°C (132.8°F)
55°C (131°F)
53°C (127.4°F) 51°C (123.8°F)
Indoor heat exchanger
thermistor temperature
Stop zone
Dropping zone
Keep zone
Up zone
Reset zone
(R14665)
D
C
B
A
E
