Heating Operation; Dry Operation - Fujitsu ASU18RLF Service Instructions Manual

2. HEATING OPERATION

2-1 HEATING 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 lower by 6°F(3°C) than a set temperature, the compressor operation
frequency will attain to maximum performance.
* If the room temperature is higher 5°F(2.5°C) than a set temperatire, the compressor will be
stopped.
* When the room temperature is between +5°F(+2.5°C) to -6°F(-3°C) of the setting temperature,
the compressor frequency is controlled within the range shown in Table2.
( Table2 : Compressor Frequency Range )
ASU18RLF
ASU24RLF

3. DRY OPERATION

3-1 INDOOR UNIT CONTROL
The compressor rotation frequency shall change according to the temperature, set temperature,
and room temperature variation which the room temperature sensor of the indoor unit body has
detected as shown in the Table3.
However, after the compressor is driven, the indoor unit shall run at operation frequency of
30rps (18RLF), 30rps (24RLF), for a minute.
( Table3 : Compressor frequency )
X zone
18RLF
J zone
Y zone
( Fig.2 : Compressor Control based on Room Temperature )
Room
temperature
X zone
Ts+1°F
(Ts+0.5°C)
J zone
Ts-3°F
(Ts-1.5°C)
Y zone
minimum maximum
frequency frequency
14rps 67rps
16rps 90rps
Operating
frequency
25rps
24RLF
15rps
0rps
Room
temperature
Ts+3°F
(Ts+1.5°C)
Ts-1°F
(Ts-0.5°C)
Operating
frequency
X zone 29rps
J zone
16rps
Y zone
0rps
01-02