Fan Speed Control For Indoor Units - Daikin Super Multi NX FFQ25B8V1B Service Manual

SiBE121021_C
1.5

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 311, 313.
Automatic Fan In automatic fan speed operation, the step "SL" is not available.
Speed Control
LLL
LL
L
ML
M
MH
H
HH (POWERFUL)
<Cooling>
The following drawing explains the principle of fan speed control for cooling.
Wall Mounted Type, Floor Standing Type
*In automatic fan speed operation, upper limit is at M tap in 30 minutes from the operation start.
Floor / Ceiling Suspended Dual Type, Duct Connected Type
<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 + 40 ~ 90 rpm.
2. Fan stops during defrost operation.
Function and Control
Step Cooling
= The airflow rate is automatically controlled within this range when the FAN setting
button is set to automatic.
fan speed
+2.5°C
+1.5°C
+0.5°C
fan speed
+1.5˚C
+0.5˚C
Function of Indoor Unit (RA Models)
Wall Mounted Type
Floor Standing Type
Heating
(R6834)
(R11681)
Room thermistor temperature – target temperature
MH*
+3°C
M
+2°C
ML
+1°C
L
Room thermistor temperature – target temperature
M
+2˚C
ML
+1˚C
L
Floor / Ceiling Suspended Dual Type
Duct Connected Type
Cooling Heating
(R6833)
(R12317)
(R12390)
(R6834)
89