Cooling Operation - Fujitsu ASU18RLF Service Instructions Manual

1. COOLING OPERATION

1-1 COOLING CAPACITY CONTROL
A sensor (room temperature thermistor) built in the indoor unit body will usually perceive
difference or variation between a set temperature and present room temperature, and
controls the operation frequency of the compressor.
* If the room temperature is 4°F(2°C) higher than a set temperature, the compressor operation
frequency will attain to maximum performance.
* If the room temperature is 5°F(2.5°C) lower than a set temperature, the compressor will be
stopped.
* When the room temperature is between +4°F(+2°C) to -5°F(-2.5°C) of the setting temperature,
the compressor frequency is controlled within the range shown in Table1.
However, the maximum frequency is limited in the range shown in Figure1 based on the
fan speed mode and the outdoor temperature.
( Table1 : Compressor Frequency Range )
ASU18RLF
ASU24RLF
( Fig.1 : Limit of Maximum Frequency based on Outdoor Temperature )
Outside air
temperature
A zone
93.2°F
(34°C)
B zone
86°F
(30°C)
C zone
66.2°F
(19°C)
D zone
50°F
(10°C)
E zone
32°F
(0°C)
F zone
minimum maximum
frequency frequency
12rps 55rps
16rps 72rps
Outside air
temperature
96.8°F
(36°C)
89.6°F
(32°C)
69.8°F
(21°C)
53.6°F
(12°C)
35.6°F
(2°C)
Hi
18RLF
A zone 55rps
B zone 55rps
C zone 47rps
D zone 37rps
E zone 37rps
F zone 37rps
24RLF
A zone 72rps
B zone 72rps
C zone 55rps
D zone 43rps
E zone 43rps
F zone
41rps
01-01
Me Lo Quiet
36rps 29rps 25rps
36rps 29rps 25rps
36rps 29rps 25rps
33rps 26rps 20rps
33rps 26rps 20rps
33rps 26rps 20rps
49rps 41rps 29rps
49rps 41rps 29rps
41rps 36rps 29rps
36rps 31rps 20rps
36rps 31rps 20rps
36rps 31rps 20rps