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Si12-411A
Main Functions
Function and Control
75
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 phase control and
hall IC
control.
For more information about hall IC, refer to the troubleshooting for fan motor on page 174.
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 operates H tap + 50 - 90 rpm.
2. Fan stops during defrost operation.
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 (Heating thermostat OFF)
20 · 25 · 35kW class :
500 - 860 rpm
(During powerful operation :
850 - 910 rpm)
50 · 60 · 71kW class :
750 - 1000 rpm
(During powerful operation :
1050 rpm)
LL (Cooling thermostat OFF)
SL (Silent)
L
ML
M
MH
H
HH (Powerful)
(R2818)
(R2818)
-1.5˚C
-0.5˚C
-1˚C
-2˚C
L
ML
M
Thermostat
setting
temperature
Phase control
Difference between room
and set temperature
fan speed
(R2819)
+1.5˚C
+0.5˚C
+2˚C
+1˚C
M
ML
L
fan speed
Difference between room
and set temperature
Phase control
Thermostat
setting
temperature
(R2820)
Summary of Contents for FTKE25BVM
Page 1: ...C Series Applied Models zInverter Multi Cooling Only zInverter Multi Heat Pump Si12 411A...
Page 6: ...Si12 411A Table of Contents v Index i Drawings Flow Charts v...
Page 7: ...Si12 411A vi Table of Contents...
Page 67: ...Specifications Si12 411A 56 Specifications...
Page 173: ...Instruction Si12 411A 162 System Configuration...
Page 227: ...Check Si12 411A 216 Service Diagnosis...
Page 295: ...Si12 411A iv Index...
Page 298: ...Si12 411A Printed in Singapore 03 2005 AK COS...