Si12-714
Main Functions
Function and Control
59
1.3
Fan Speed Control
for Indoor Units
Control Mode
The airflow rate can be automatically controlled depending on the difference between the set
temperature and the room temperature. This is done through rotation speed control, or phase
and
Hall IC
control.
For more information about Hall IC, refer to the troubleshooting for fan motor on page 182.
Fan speed Steps
Fan speed control contains 9 steps: LLL, LL, SL, L, ML, M, MH, H and HH.
In automatic operation, the step “SL” is not available.
= Within this range the airflow rate is automatically controlled when the FAN setting
button is set to automatic.
Note:
1. During powerful operation, fan rotates at H tap + 50 - 90 rpm.
2. Fan stops during defrost operation.
Automatic Air
Flow Control for
Heating
On heating mode, the indoor fan speed will be regulated according to the indoor heat exchanger
temperature and the difference between the room temperature and the required set point.
Automatic Air
Flow Control for
Cooling
The following drawing explains the principle of fan speed control for cooling:
Step
Cooling
Heating
LLL
LL
L
ML
M
MH
H
HH (Powerful)
(R2818)
(R5229)
+1.5˚C
+0.5˚C
+2˚C
+1˚C
M
ML
L
fan speed
Difference between room
and set temperature
Thermostat
setting
temperature
(R4594)
DC motor: Rotation speed control
AC motor: Phase control
