Daikin FVKS25BVMB, Service Manual

Page: 31 / 184

Main Functions SiBE06-514A
22 Function and Control
1.4 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 phase control and Hall IC control.
For more information about Hall IC, refer to trouble shooting for fan motor on page 87.
Phase Steps Phase control and fan speed control contains 9 steps: LLL, LL, SL, L, ML, M, MH, H and HH.
= 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.
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 keeps rotating at LLL tap.
Automatic Air
Flow Control for
Heating The following drawing explains the principle for fan speed control for heating:
Automatic Air
Flow Control for
Cooling The following drawing explains the principle of fan speed control for cooling:
Step Cooling Heating Dry mode
LLL
25 · 35kW class :
740 - 760 rpm
(During powerful operation :
970rpm)
LL
SL (Silent)
L
ML
M
MH
H
HH (Powerful)
(R4085) (R4085)
-1.5˚C
-0.5˚C
-1˚C
-2˚C
L
ML
M
Thermostat
setting
temperature
DC motor: Rotation speed control
Difference between room
and set temperature
fan speed
(R4558)
+1.5˚C
+0.5˚C
+2˚C
+1˚C
M
ML
L
fan speed
Difference between room
and set temperature
DC motor: Rotation speed control
Thermostat
setting
temperature
(R4559)