Heating Operation - Fujitsu AB F18LAT Series Service Instruction

1-2. HEATING OPERATION

1-2-1 HEATING CAPACITY CONTROL
A sensor (room temperature thermistor) built in the indoor unit will usually perceive
difference or variation between a set temperature and present room temperature, and
controls the operation frequency of the compressor.
The maximum frequency is limited in the range shown in Figure 2 based on the outdoor temperature.
* If the room temperature is lower 3 degC than a set temperature,
the compressor operation frequency will attain to maximum frequency.
* If the room temperature is higher 2.5 degC than a set temperature, the compressor
will be stopped.
* When the room temperature is between +2.5 degC to -3 degC of the setting temperature,
the compressor frequency is controlled within the range shown in Table2.
( Table 2 : Compressor Frequency Range )
AB*F18, 24
AR*F18, 24
AU*F18, 24
AR*A24LATU
AU*A24LBL
( Fig.2 : Limit of Maximum Frequency based on Outdoor Temperature )
Outdoor air
When the room
temperature rises
temperature
19°C
14°C
minimum maximum
frequency frequency
18Hz 120Hz
18Hz 120Hz
C zone
17°C
B zone
12°C
A zone
When the room
temperature drops
Fan speed mode
A zone
AB*F18, 24
AR*F18, 24
B zone
AU*F18, 24
C zone
AR*A24LATU A zone
AU*A24LBL
B zone
C zone
01-02
Hi
Me Lo
Me+
120Hz 101Hz 70Hz
120Hz 101Hz 70Hz
120Hz 113Hz 113Hz
120Hz 101Hz 75Hz
120Hz 101Hz 75Hz
120Hz 101Hz 75Hz
Quiet
60Hz
60Hz
70Hz
60Hz
60Hz
60Hz