Fan Speed Control For Indoor Units - Daikin FTKS20D3VMW Service Manual

SiENBE12-713
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 the troubleshooting for fan motor on page 239.
Phase Steps Phase control and 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.
LLL
LL
L
ML
M
MH
H
HH (Powerful) H+70 (FTXG25/35E)
Note: 1. Fan stops during defrost operation.
2. In time of thermostat OFF, the fan rotates at the following speed.
Automatic Air
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.
Flow Control for
Heating
Automatic Air
The following drawing explains the principle of fan speed control for cooling:
Flow Control for
Cooling
Function and Control
FTXG25/35E
CTXG50E
FVXS25-50F
Step Cooling
(R6035)
H+50 (CTXG50E)
H+40 (FVXS25-50F)
= Within this range the airflow rate is automatically controlled when the FAN setting
button is set to automatic.
Cooling : The fan keeps rotating at the set tap.
Heating : The fan stops.
fan speed
+1.5°C +1.5°C
+0.5°C +0.5°C
Thermostat
setting
temperature
DC motor: Rotation speed control
AC motor: Phase control
FTK(X)S50-71E
FTK(X)S71B
Heating Cooling Heating Cooling Heating
(R6037)
(R6036)
H+50 (FTXG25/35E, H+90
CTXG50E)
H+40 (FVXS25-50F)
M
Difference between room
+2°C +2°C
ML
and set temperature
+1°C +1°C
L
Main Functions
FTK(X)S20-50D
FTK(X)S20-35CA
FDK(X)S25-35EA
FDK(X)S25-35CA
FDK(X)S50-60C
FLK(X)S25-60BA
(R6037)
(R6036) (R6036)
H+90 H+50 H+50
(R4594)
65