OUND DIFFUSER

CHAPTER-7
ROUND DIFFUSERS
INDEX
o Round Diffusers

o Description & Construction

o Finish

o Types Available

o Product Model Description

o Standard Sizes of Tecnalco Model

o Performance Data

o Installation Details & Ordering Data

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ROUND DIFFUSERS TECNALCO

ROUND DIFFUSERS

Description & Construction

‘TECNALCO’ Round Diffusers are designed to provide supply or return of conditioned air at acceptable
sound levels, pressure drops and uniform radial discharge in supply air application & are suitable for
supplyair temperature differentials of +10K to 10 K

The Round Diffusers are constructed from high quality aluminium sheet & having sheet thickness about 1.25 mm.

Inner cores are fixed rigidly with the frame.

Gasket is sealed around the back of the frame to avoid air leakage.

Butterfly Damper is fixed with the frame by rivets.(standard)

Butterfly Damper operated through Diffuser face.( stud adjustable)

Butterfly Damper is made of galvanised steel sheet having thickness 1.0mm.

Finish

Powder coated colour finish (Mention RAL Colour number).

Aluminium mill finish.

Damper : Black matt finish.

Types available

Supply Diffuser Return Diffuser

SCD ‘TF’ RCD ‘TF’

Only removable type

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ROUND DIFFUSERS TECNALCO

PRODUCT MODEL DESCRIPTION

Supply Round Diffusers

SCD - TF

Supply Round Diffusers, SCD ‘TF’ are diffusers with

butterfly damper, can be used for supply air. They are
suitable for installation in ceilings.The circular design
guarantees a uniform radial discharge in supply air
application.

Diffuser with Damper

Return Round Diffusers

RCD - TF

Return Round Diffusers, RCD ‘TF’ are diffusers

without damper. They can be used for
Extract air, Suitable for installation in ceilings.

Diffuser without Damper

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ROUND DIFFUSERS TECNALCO

STANDARD SIZES OF TECNALCO MODEL

TYPE : SCD - TF
RCD - TF

NECK SIZE ‘A’- OUTER SIZE ‘B’- FLANGE DIFFUSER

WIDTH HEIGHT
S. No. ‘C’ ‘H’
Inch mm Inch mm mm mm

1. 5.3 134 9.8 250 30 40

2. 7.5 190 12.1 307 30 40

3. 9.7 247 14.3 363 30 40

4. 11.9 303 16.5 419 30 40

5. 14.3 362 18.8 478 30 40

6. 16.4 416 21.0 534 30 40

7. 18.5 469 23.5 598 35 40

8. 20.5 521 25.7 653 35 40

9. 22.6 573 27.7 704 35 40

10. 24.6 625 29.8 756 35 40

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ROUND DIFFUSERS TECNALCO

ACCESSORY

Volume Control Damper (Butterfly Type) :

Volume Control Damper is an adjustable device used to control the volume of air passing through an air
outlet or inlet and mounting in Diffuser neck. Adjustable through diffuser neck.

Butterfly Damper

Standard type

Adjustable stud type

Available Sizes :

Minimum Maximum

5.3” (134 mm) Dia. 24.6” (625 mm) Dia.

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ROUND DIFFUSERS TECNALCO

Performance Data

Neck Neck Velocity 1.52 2.03 2.54 3.05 3.56 4.06 5.08 6.10
Dia. Neck Area m/s
Area Factor
mm
& m2 Velocity Pr. 1.74 2.73 3.98 5.72 7.71 10.19 15.91 22.62
(inch Pa

Air flow rate 28 38 47 57 64 73 92 111

L/s
Total pr. Drop 7.5 13.4 20.9 30.3 38.0 50.2 79.6 115.5
134
0.014 0.006 Pa
(5.3) Throw (m) 0.6-1.8 0.9-2.1 0.9-2.4 1.2-3.0 1.5-3.3 1.8-3.3 1.8-3.7 2.1-4.0

NC (dB) <15 <15 15 20 24 28 34 40

Air flow rate 50 66 83 99 116 132 165 198

L/s
Total pr. Drop 8.7 15.7 24.4 34.8 47.7 62.2 97.0 139.2
190
0.028 0.013 Pa
(7.5) Throw (m) 1.2-2.7 1.5-3.0 1.8-3.4 1.8-4.0 2.1-4.3 2.4-4.6 2.7-7.9 2.7-5.2

NC (dB) <15 15 21 26 31 35 41 46

Air flow rate 78 104 130 153 179 205 257 309
L/s
Total pr. Drop 9.2 16.2 26.8 35.0 47.9 63.1 98.7 142.2
247
0.048 0.022 Pa
(9.7) Throw (m) 1.5-3.4 1.8-4.0 2.1-4.3 2.1-4.6 2.4-4.9 2.7-5.2 3.0-5.5 3.4-6.1

NC (dB) <15 19 25 30 35 39 45 49

Air flow rate 106 149 186 222 260 297 370 444
L/s
Total pr. Drop 8.7 17.2 26.6 38.0 52.0 68.4 105.7 151.6
303
0.072 0.033 Pa
(11.9) Throw (m) 2.1-4.3 2.4-4.9 2.7-5.2 3.0-5.5 3.4.-5.8 3.7-6.1 4.3-6.4 4.6-6.7

NC (dB) <15 20 27 32 37 40 47 50

Air flow rate 151 203 252 302 354 403 505 606
L/s
Total pr. Drop 9.4 17.2 26.8 38.0 52.2 68.1 106.9 154.1
362
0.103 0.047 Pa
(14.3) Throw (m) 2.4-4.9 2.7-5.5 3.0-5.8 3.4-6.1 3.7-6.1 4.0-6.4 4.6-6.7 4.9-7.3

NC (dB) <15 21 28 33 38 41 48 53

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ROUND DIFFUSERS TECNALCO

Performance Data cont’d.

Neck Neck Velocity 1.52 2.03 2.54 3.05 3.56 4.06 5.08 6.10
Dia. Neck Area m/s
Area Factor
mm
& m2 Velocity Pr. 1.74 2.73 3.98 5.72 7.71 10.19 15.91 22.62
(inch Pa

Air flow rate 198 264 330 396 462 529 661 793
L/s
Total pr. Drop 7.0 12.7 19.6 28.3 38.8 50.7 79.1 114.4
416
0.140 0.063 Pa
(16.4) Throw (m) 2.7-5.5 3.0-6.1 3.4-6.4 3.7-6.4 4.0-6.7 4.3-7.3 4.9-7.6 5.5-7.9

NC (dB) <15 21 28 33 38 41 48 53

Air flow rate 250 335 418 500 585 668 835 1003
L/s
Total pr. Drop 5.22 9.70 14.67 21.38 29.09 37.79 59.66 94.47
469
0.172 0.078 Pa
(18.5) Throw (m) 2.7-5.5 3.0-6.1 3.4-6.7 3.7-7.0 4.3-7.3 4.6-7.6 5.2-8.2 5.5-8.5

NC (dB) <15 22 28 33 38 41 48 53

Air flow rate 311 401 519 613 722 826 1015 1251
L/s
Total pr. Drop 5.72 9.70 16.41 22.87 31.32 40.77 62.15 94.47
521
0.213 0.100 Pa
(20.5) Throw (m) 2.7-5.5 3.0-6.1 3.7-6.7 4.0-7.0 4.6-7.3 4.9-7.9 5.2-8.2 5.5-8.5

NC (dB) 16 22 28 33 39 42 48 53

Air flow rate 375 479 625 737 871 996 1227 1521
L/s
Total pr. Drop 5.4 10.8 16.67 24.19 31.79 41.28 62.37 93.37
573
0.258 0.122 Pa
(22.6) Throw (m) 2.7-5.5 3.0-6.1 3.5-6.7 3.8-7.0 4.4-7.3 4.7-7.7 5.2-8.2 5.5-8.5

NC (dB) 17 23 28 33 40 43 48 53

Air flow rate 444 590 741 873 1038 1180 1477 1817
L/s
Total pr. Drop 5.72 9.70 15.16 21.13 29.83 38.53 59.66 91.98
625
0.307 0.146 Pa
(24.6) Throw (m) 2.7-5.5 3.0-6.1 3.4-6.7 3.7-7.0 4.2-7.3 4.6-7.6 5.2-8.2 5.5-8.5

NC (dB) 18 24 29 34 40 43 49 54

Note :
Throw data is based on teminal velocity of 0.76 m/s and 0.25 m/s.
Sound data - NC(Noise Criteria) values are based upon a room absorption of 10 dB, re 10-12 watts.

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 ROUND DIFFUSERS TECNALCO

INSTALLATION DETAILS

The attractively shaped Supply/Return diffuser can be installed by means of a fixing clamp and central screw
as shown below.

Duct Fixing Clamp

Duct

Installtion With Duct Fixing Clamp

Ordering Data:
Specify
1. Tecnalco type and model
2. Neck Size ‘A’ - mm
3. Quantity
4. Surface Finish
5. Remarks

Example

1. 2. 3. 4. 5.

Refer table Powder Coated

SCD / RDC ‘TF’ 50 nos.
@page no 7-5 RAL