Fujitsu ASU18RLF Service Instructions Manual page 8

5. HEATING OPERATION
Switch the airflow [AUTO], and the indoor fan motor will run according to a room temperature,
as shown in Figure4.
On the other hand, if switched in [HIGH]
of [HEAT] operation modes QUIET, LOW, MED, HIGH, as shown in Table4.
( Fig.4 : Airflow change - over ( Heating : AUTO ) )
TR-Ts > -2°F
=
(-1°C)
-2°F > TR-Ts > -4°F
=
(-1°C) (-2°C)
-4°F > TR-Ts
(-2°C)
6. COOL AIR PREVENTION CONTROL (Heating mode)
The maximum value of the indoor fan speed is set as shown in Figure5, based on the detected
temperature by the indoor heat exchanger sensor on heating mode.
(Fig.5 : Cool Air Prevention Control)
Indoor heat exchanger
temperature
107.6°F (42°C)
102.2°F (39°C)
98.6°F (37°C)
86°F (30°C)
[QUIET], the indoor motor will run at a constant airflow
When the room
temperature rises
LOW mode
MED mode
MED+ mode
Indoor heat exchanger
temperature
Hi
Me+
Lo
Cool air
prevention
S-Lo
When the room
temperature drops
TR-Ts > -3°F
=
(-1.5°C)
-3°F > TR-Ts > -5°F
(-1.5°C)
-5°F > TR-Ts
(-2.5°C)
98.6°F (37°C)
93.2°F (34°C)
89.6°F (32°C)
82.4°F (28°C)
01-05
=
(-2.5°C)
TR : Room temperature
Ts : Setting temperature