Heating Operation - Fujitsu ASUH24LPAS Service Manual

1-2. Heating operation

A sensor (room temperature thermistor) built in indoor unit body will usually perceive difference or
variation between setting temperature and present room temperature, and controls operation rota-
tion number of compressor.
• If the room temperature is 11 °F (6.0 °C) lower than a set temperature, the operation rotation num-
ber of compressor will attain to maximum performance.
• If the room temperature is 2 °F (1.0 °C) higher than a set temperature, the compressor will be
stopped.
• When the room temperature is within the range of +2 °F (1.0°C) to -11 °F (6.0°C) of the setting
temperature, the rotation number of compressor is controlled within the range shown below.
• Rotation number range of compressor
Model name
ASUH18LPAS
ASUH24LPAS
• Limit of maximum speed based on outdoor temperature
In heating operation, maximum rotation number is defined by outdoor temperature and fan mode.
Model name
ASUH18LPAS
ASUH24LPAS
1-2. Heating operation
Minimum frequency
Outdoor
temperature rises
57.2°F
(14°C)
14.0°F
(-10°C)
Outdoor
temperature zone
A zone
B zone
C zone
A zone
B zone
C zone
- (04-3) -
8
Outdoor
temperature drops
C zone
53.6°F
(12°C)
B zone
10.4°F
( -12 °C)
A zone
Indoor unit fan mode
HIGH MED
130 111
130 111
130 111
130 130
130 130
130 130
Unit: rps
Maximum frequency
130
Unit: rps
LOW QUIET
68 50
68 50
68 50
102 68
102 68
102 68
1. Rotation number control of compressor