Main Functions
SiBE04-808_B
33
Function and Control
1.3
Fan Speed Control for Indoor Units
Outline
Phase control and fan speed control contains 9 steps: LLL, LL, SL, L, ML, M, MH, H, and HH.
The airflow rate can be automatically controlled depending on the difference between the room
thermistor temperature and the target temperature. This is done through phase control and Hall
IC control.
For more information about Hall IC, refer to the troubleshooting for fan motor on page 107.
Automatic Fan
Speed Control
In automatic fan speed operation, the step “SL” is not available.
= The airflow rate is automatically controlled within this range when the FAN setting
button is set to automatic.
<Cooling>
The following drawing explains the principle of fan speed control for cooling.
*In automatic fan speed operation, upper limit is at M tap in 30 minutes from the operation start.
<Heating>
On heating mode, the fan speed is regulated according to the indoor heat exchanger
temperature and the difference between the room thermistor temperature and the target
temperature.
Note:
1. During POWERFUL operation, fan rotates at H tap + 50 rpm.
2. Fan stops during defrost operation.
3. In time of thermostat OFF, the fan rotates at the following speed.
Cooling: The fan keeps rotating at the set tap.
Heating: The fan stops.
COMFORT
AIRFLOW
Operation
The fan speed is controlled automatically within the following steps.
Cooling: L tap – MH tap (same as AUTOMATIC)
Heating: ML tap – Equivalent to ML tap – MH tap
The latest command has the priority between POWERFUL and COMFORT AIRFLOW.
Step
Cooling
Heating
LLL
LL
L
ML
M
MH
H
HH (POWERFUL)
(R6833)
(R6834)
(R12317)
fan speed
+2.5°C
+1.5°C
+0.5°C
MH*
M
ML
L
+3°C
+2°C
+1°C
Difference between the room
thermistor temperature and
the target temperature
