Fresh Air Intake Unit _ 13
Indoor Units
9. Sound Levels
Overall
1.5m
2m
2m
DUCT
DISCHARGE
SUCTION
DUCT
❈ Measuring place : Anechoic chamber
Model
Sound Pressure Levels
HML
ARNU48GBRZ4 41 40 38
ARNU76GB8Z4 45 43 43
ARNU96GB8Z4 47 45 45
Notes:
1. Sound measured at 1.5m away from the center of the unit
2. Operating condition|
- Cooling : Outdoor temperature (33°C DB, 28°C WB) 
- Heating : Outdoor temperature (0°C DB, -2.9°C WB)
3. Reference accoustic pressure 0dB = 20μPa
4. Sound level will vary depending on a range of factors such as the
construction(acoustic absorption coefficient) of particular room in
which the equipment in installed.
[dB(A)]
Octave Band Sound Pressure Level (0 dB = 20 μPa)
Octave Band Sound Pressure Level (0 dB = 20 μPa)
Octave Band Center Frequency (Hz)
10 
20 
30 
40 
50 
60 
70 
80 
63  125  250  500  1 000  2 000  4 000  8 000 
NC-15 
NC-20 
NC-25 
NC-30 
NC-35 
NC-40 
NC-45 
NC-50 
NC-55 
NC-60 
NC-65 
Approximate
Hearing
Threshold    
Octave Band Center Frequency (Hz)
10 
20 
30 
40 
50 
60 
70 
80 
63  125  250  500  1 000  2 000  4 000  8 000 
NC-15 
NC-20 
NC-25 
NC-30 
NC-35 
NC-40 
NC-45 
NC-50 
NC-55 
NC-60 
NC-65 
Approximate
Hearing
Threshold    
Octave Band Sound Pressure Level (0 dB = 20 μPa)
Octave Band Center Frequency (Hz)
10 
20 
30 
40 
50 
60 
70 
80 
63  125  250  500  1 000  2 000  4 000  8 000 
NC-15 
NC-20 
NC-25 
NC-30 
NC-35 
NC-40 
NC-45 
NC-50 
NC-55 
NC-60 
NC-65 
Approximate
Hearing
Threshold    
ARNU48GBRZ4 ARNU76GB8Z4 ARNU96GB8Z4 
n High
▲ Mid
l Low
n High
▲ Mid
l Low
n High
▲ Mid
l Low
9.1 Sound Pressure Levels