Indoor Unit (RA Models)
Si18-525B
134
Function
7.2
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 332.
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.
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
Dry mode
LLL
20 · 25 · 35kW class :
670 - 880 rpm
(During powerful operation :
720 - 930 rpm)
50 · 60 · 71kW class :
750 - 1000 rpm
(During powerful operation :
1050 rpm)
LL
SL (Silent)
L
ML
M
MH
H
HH (Powerful)
(R2818)
(R2818)
+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
Summary of Contents for D-Series
Page 1: ...Si18 525B Applied Models Super Multi Plus Cooling only Super Multi Plus Heat Pump D Series ...
Page 33: ...List of Functions Si18 525B 20 List of Functions ...
Page 71: ...Specifications Si18 525B 58 Specifications ...
Page 117: ...Refrigerant Flow for Each Operation Mode Si18 525B 104 Refrigerant Circuit ...
Page 171: ...Indoor Unit SkyAir Models Si18 525B 158 Function ...
Page 207: ...Test Operation and Field Setting for RA Indoor Unit Si18 525B 194 Test Operation ...
Page 336: ...Si18 525B Service Check Function Troubleshooting 323 ...
Page 469: ...Wiring Diagrams Si18 525B 456 Appendix ...
Page 475: ...Si18 525B vi Index ...