TECHNICAL - SQUARE CEILING DIFFUSERS
Square Ceiling Diffusers
NECK SIZE (mm) 225 x 225
300 x 300
375 x 375
450 x 450
Model LFD
STATIC PRESSURE DROP (Pa)
NR (dB)
Minimum Throw (m)
Maximum Throw (m)
2
15
<22
0.5
1.5
150
3
35
28
1.4
3.2
150 200
1.7
12
<22
0.9
2.7
2.2
19
23
1.4
3.3
Airflow (L/s) Velocity (m/s) 100
250
2.8
31
26
2.2
4.2
300
3.3
42
31
2.8
4.6
250
1.8
13
<22
1.3
3.4
300
2.1
18
<22
1.5
3.9
350
2.5
26
28
1.7
4.6
400
2.9
32
31
2.1
5
450
3.2
39
35
2.7
5.2
350
1.7
12
25
1.2
3.8
400
2
15
26
1.4
4.2
450
2.2
20
29
2
4.8
500
2.5
25
32
2.7
5.4
550
2.7
30
33
3.1
5.8
600
3.0
35
35
3.5
6.2
NOTE: The above sizes are based on a 4-way throw 3-way x Air Quantity x 0.75 2-way x Air Quantity x 0.50
Opposed Blade Dampers - Effect of Volume Control on Noise Levels The additional noise level for diffusers with Opposed Blade Dampers installed is set out in the following table:
NR Addition for OBD
158
Diffuser with OBD
Fully Open
50% Closed
NR 25 or less
1
5
NR 30
1
6
NR 35
2
8
All sales are made on the basis of the ‘Terms and Conditions of Trade’ contained in this Product Catalogue Edition 1. ©2018 Polyaire™ Pty Ltd. The manufacturer reserves the right to alter product specifications without notice. E. & O.E. Conditions Apply.