Round Diffusers

Technical Catalogue

Round Diffusers

Round Diffusers are intended for application in air conditioning and ventilation systems in civil as well as industrial zones. Employed to diffuse and extract the air from large ambient. Suitable for heating, cooling and ventilation system for wide diffusing effect. Can be installed on false ceiling or exposed duct work. Diffusers with fully adjustable Aluminium sheet cores provide horizontal or vertical air pattern and longer throw. Adjustable cones offer high degree of mixing of primary air and secondary air which ensures efficient air distribution.

Round Diffusers

Ref:GD1000RD

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Introduction

1

Construction & Application

Round diffusers are designed for ceiling and duct mounting applications. Standard indoor air supply with controlled performance can be attained. Round ceiling diffusers are multi coned diffusers, they offer a unique role in diffusing and exhausting air to and from the conditioned space. Suitable for offices, shops or similar premises where adjustable patterned diffusion is essential for cold and warm air distribution.

Frame/Inner core Aluminium Sheet Construction.

Finish Electrostatic Polyester powder coated /RAL code.

Fixing On Ceiling and exposed duct.

Shape Circular/Round.

Round Diffusers are common in heating, ventilating and air conditioning systems.

Round ceiling diffusers are multi-core diffusers and they help in diffusing and exhausting air to and from the conditioned space.

Used in high ceiling application ensuring deeper drop.

Essential to distribute the flow of air in the desired directions and to enhance the thrust.

Round diffusers are used where continuous air movement is essential in the occupied portion of the room.

Suitable for ceilings with mounting height ranges from 2.5M to 4M. Also suitable for non-ceiling

Suitable for offices, shops, or similar premises where adjustable patterned diffusion is essential and for cold and warm air distribution.

Round diffusers ensure low pressure drop, low noise, high induction rate with uniform air circulation.

IntroductionRound Diffusers

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Assembling Features

2

Adjustable core ceiling Diffusers include, ceiling-mounted external frame and internally adjustable core. Adjustable center cores provide both horizontal and vertical air flow and air pattern adjustments.

Rotating the cones allow vertical air distribution with minimum induction and unscrewing of the inner cones allows horizontal distribution of air with maximum induction.

The core is spindled with a threaded rod and assembled in a manner to hold one or more intermediate inverted curved cores through the threaded rod and screwed to the external frame flange.

Wall mountable external and snap-in internal cones are manufactured from aluminium sheets by spinning process.

Centre cone assembly can be detached or attached by rotating clock-wise or anti clock-wise direction. This helps to clean up the inner surfaces and to adjust the butterfly damper.

Removable core is designed for quick installation and for a fine finished look. Maintenance and servicing of the duct system is made easier by dismantling the cores.

External cores of the unit can be fixed to the ceiling by pop rivets or screws and inner double cones can be assembled into it by pressing and turning.

Fixed core Round Diffusers are constructed by high quality, corrosion resistance aluminium sheet frame and cores / cones.

Inner module / Cores are assembled together by means of 8mmØ round pipe, placed in position by means of spring loaded Diffuser pins. Center module is removable from the face of the Diffuser by twisting clock-wise or anti clock-wise.

These Diffusers can be used for ceiling or exposed ducts for supply or exhaust air applications.

Optional rubber foam gasket may be affixed to seal the surface around the back of the frame to avoid air leakage and smudging.

Diffusers are available in a wide array of neck sizes ranging from 150mm to 400mm.

Standard available finished product is, with visible screw fixing on Ceiling, exposed ducts and walls.

Supply Round Diffusers are supplied with Butterfly Damper (in Black colour finish) to control the air volume flowing across the Diffuser. Damper is fixed to the diffuser by rivets and it can be operated by screw driver from the Diffuser face for desired adjustment.

Assembling FeaturesRound Diffusers

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Constructional Details

3

EF

L = Listed Size

A = Collar ID or Duct ID

Duct

Butterfly Damper

Screw

Diffuser

C = Diffuser Overall Diameter

B = False Ceiling Opening

D

Adjustable Core (Type - A)

Dimensional Details

Quick Selection Guide

Listed Size in mm / inch. No. of Cores CFM Range

150mm Ø 2 60 - 315

200mm Ø 2 105 - 560

250mm Ø 3 165 - 870

300mm Ø 3 235 - 1255

350mm Ø 3 320 - 1710

400mm Ø 3 420 - 2240

6“ Ø

8“ Ø

10” Ø

12” Ø

14” Ø

16” Ø

(mm) (Inches)

Listed Sizes Dimension in mm

150 Ø

200 Ø

250 Ø

300 Ø

350 Ø

400 Ø

6 Ø 144

A Ø

290 315 45 22 9

B Ø C Ø D Ø E Ø F Ø

194 384 422 59 25.5 11

244 475 528 80 33 12.5

294 564 635 94 42 15

344 637 690 100 45 19

394 737 764 112 48 22

8 Ø

10 Ø

12 Ø

14 Ø

16 Ø

Constructional DetailsRound Diffusers

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Constructional Details

4

L = Listed Size

A = Ceiling Opening Diameter

B = Diffuser Overall Diameter

C

D

Duct

Butterfly Damper

Rivet

Diffuser

Fixed Core (Type - B)

Dimensional Details

Quick Selection Guide

Listed Size in mm / Inch No. Of Cores CFM Range

150mm Ø 2 49 - 175

200mm Ø 3 92 - 322

250mm Ø 4 144 - 504

300mm Ø 5 216 - 756

350mm Ø 6 289 - 1010

400mm Ø 7 390 - 1365

6“ Ø

8“ Ø

10” Ø

12” Ø

14” Ø

16” Ø

Dimension in mm

150 Ø

200 Ø

250 Ø

300 Ø

350 Ø

400 Ø

6 Ø

A Ø

225

282

330

382

440

482

255

312

360

412

470

512

50

53

54

55

58

60

5

5

5

6

6

6

B Ø C Ø D Ø

8 Ø

10 Ø

12 Ø

14 Ø

16 Ø

Listed Sizes (L)

(mm) (Inches)

Constructional DetailsRound Diffusers

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Accessories

5

A

Mounting Taps

140

Max

.Ope

ning

Heigh

t

BC

N

D

Butterfly Damper (For Type - A & B)

Butterfly Damper Dimensions

Nominal (N)/Listed Sizes(L) A Ø B Ø C Ø D Ø

150 Ø mm

200 Ø mm

250 Ø mm

300 Ø mm

350 Ø mm

400 Ø mm

153mm

203mm

253mm

303mm

353mm

403 mm

20mm

20mm

20mm

20mm

20mm

20mm

72mm

72mm

72mm

72mm

72mm

72mm

52mm

52mm

52mm

52mm

52mm

52mm

6“ Ø mm

8“ Ø mm

10“ Ø mm

12“ Ø mm

14“ Ø mm

16“ Ø mm

AccessoriesRound Diffusers

The circular body consists of two half circulars, heavy gauged galvanized iron sheet blades held by friction pivots to spin around the threaded rod positioned centrally in the butterfly damper. This enables the system for continuous adjustments to be set in a desired position.

Easily adjustable from the front face of diffuser upon removing the inner cores.The device can be mounted directly on the diffuser neck before installation.

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Installation

6

Fixed Core (Type - B)

L = Listed Size

A = Ceiling Opening Diameter

B = Diffuser Overall Diameter

C

D

Duct

Butterfly Damper

Screw

Diffuser

EF

Adjustable Core (Type - A)

L = Listed Size

A = Collar ID Or Duct ID

Duct

Butterfly Damper

Screw

Diffuser

Ceiling

C = Diffuser Overall Diameter

B = False Ceiling Opening

D

InstallationRound Diffusers

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Performance Data

7

NC (dB) 19 19 20 20 21 26 30 33 36 39 44 48

CFM 60 80 100 120 135 155 175 195 215 235 275 315

0.024 0.041 0.065 0.093 0.126 0.162 0.207 0.255 0.304 0.365 0.494 0.648

0.035 0.058 0.093 0.133 0.180 0.232 0.296 0.365 0.435 0.522 0.708 0.928

Radius in Feet(Throw) 2 - 3 2 - 4 3 - 5 3 - 5 4 - 6 4 - 6 5 - 7 5 - 7 5 - 7 6 - 8 6 - 8 7 - 9

NC (dB) 19 19 19 20 20 23 26 30 33 35 40 44

CFM 105 140 175 210 245 280 315 350 385 420 490 560

0.017 0.029 0.046 0.066 0.088 0.114 0.145 0.180 0.214 0.257 0.348 0.456

0.026 0.044 0.070 0.101 0.136 0.176 0.224 0.277 0.330 0.396 0.537 0.704

Radius in Feet 2 - 4 3 - 5 4 - 6 4 - 7 5 - 7 6 - 8 6 - 8 7 - 9 7 - 10 7 - 10 8 - 11 9 - 12

NC (dB) 20 20 20 21 26 31 34 37 40 44 48 50

CFM 165 220 275 325 380 435 490 545 600 655 765 870

0.017 0.028 0.044 0.063 0.085 0.110 0.140 0.173 0.206 0.248 0.335 0.440

0.025 0.041 0.066 0.095 0.128 0.165 0.210 0.260 0.309 0.371 0.503 0.659


0.015 0.025 0.040 0.057 0.077 0.099 0.126 0.156 0.185 0.222 0.301 0.395

CFM 235 315 395 470 550 630 705 785 865 940 1100 1255

0.022 0.036 0.058 0.083 0.112 0.144 0.184 0.227 0.270 0.324 0.439 0.576


NC (dB) 19 19 20 20 22 26 30 33 36 39 45 49

CFM 320 430 535 640 750 855 965 1070 1175 1285 1500 1710

0.014 0.024 0.038 0.055 0.074 0.096 0.122 0.151 0.180 0.216 0.293 0.384

0.022 0.036 0.058 0.083 0.112 0.144 0.184 0.227 0.270 0.324 0.439 0.576


NC (dB) 20 20 20 23 28 32 36 40 43 46 48 50

CFM 420 560 700 840 980 1120 1260 1400 1540 1680 1960 2240

0.014 0.023 0.037 0.053 0.071 0.092 0.117 0.145 0.173 0.207 0.281 0.368

0.021 0.035 0.056 0.080 0.108 0.139 0.177 0.219 0.260 0.312 0.423 0.555

Radius in Feet(Throw) 5 - 7 7 - 10 8 - 12 10-13 11-15 12-16 13-17 14-18 15-19 15-20 17-21 19-23

NC (dB) 20 20 20 22 27 31 35 39 42 44 49 50

150 Ø

200 Ø

250 Ø

300 Ø

350 Ø

400 Ø

0.196

0.349

0.545

0.785

1.070

1.400

Velocity (FPM) 300 400 500 600 700 800 900 1000 1100 1200 1400 1600

Velocity Pressure in W.G. 0.006 0.010 0.016 0.023 0.031 0.040 0.051 0.063 0.075 0.090 0.122 0.160

Total Horizontal Pressure in W.G.

Total Vertical Pressure in W.G.











Size Area

(Sq. Ft.)(mm) Inches

6 Ø

8 Ø

10 Ø

12 Ø

14 Ø

16 Ø

Supply Round Ceiling Diffuser (Type - A)

RD-S/A

.G.W sehcni ni nevig si erusserP yticoleV sulp erusserP citatS fo mus ehT - erusserP latoT

Neck Velocity - Air flow rate (CFM) divided by Neck Area (Sq. Ft) equals Neck Velocity (FPM).

Radius in Feet - Radius of diffusion is based on a minimum terminal velocity of 100 FPM and a maximum terminal

velocity of 50 FPM using isothermal air and horizontal air pattern.

NC (dB), Level, dB - It is based on a room absorption of 10 dB, re 10-12 watts. Values shown are for horizontal pattern,

Add 1 dB for a vertical pattern.

Performance DataRound Diffusers


8

Size

(mm)

Area

(sq.ft)

Velocity (FPM) 300 400 500 600 700 800 900 1000 1100 1200 1400 1600

Vel. Pressure in W.G. 0.006 0.010 0.016 0.023 0.031 0.040 0.051 0.063 0.075 0.090 0.122 0.160

150 Ø 0.196

60 80 100 120 135 155 175 195 215 235 275 315

0.022 0.037 0.059 0.084 0.114 0.146 0.187 0.230 0.275 0.330 0.446 0.586

19 19 19 20 20 23 26 30 33 35 40 44

200 Ø 0.349

CFM 105 140 175 210 245 280 315 350 385 420 490 560

Neg. Stat. Pressure (W.G) 0.013 0.023 0.037 0.052 0.068 0.089 0.113 0.140 0.167 0.200 0.271 0.355

NC (dB) 20 20 20 21 26 31 34 37 40 44 48 50

250 Ø 0.545

CFM 165 220 275 325 380 435 490 545 600 655 765 870


NC (dB) 19 19 20 20 21 26 30 33 36 39 44 48

300 Ø 0.785

CFM 235 315 395 470 550 630 705 785 865 940 1100 1255


NC (dB) 19 19 20 20 22 26 30 33 36 39 45 49

350 Ø 1.07

CFM 320 430 535 640 750 855 965 1070 1175 1285 1500 1710

0.010 0.017 0.026 0.038 0.052 0.067 0.085 0.106 0.126 0.151 0.205 0.269

20 20 20 23 28 32 36 40 43 46 48 50

400 Ø 1.40

CFM 420 560 700 840 980 1120 1260 1400 1540 1680 1960 2240


NC (dB) 20 20 20 22 27 31 35 39 42 44 49 50

CFM

Neg. Stat. Pressure (W.G)

NC (dB)

Neg. Stat. Pressure (W.G)

NC (dB)

(Inches)

6 Ø

8 Ø

10 Ø

12 Ø

14 Ø

16 Ø

Return Round Ceiling Diffuser (Type - A)RD-R/A



9

Supply Round Ceiling Diffuser (Type - B)

Size mmArea Factor

Ak in sq.ft

Face Velocity

in fpm

400

150 Ak=0.124

cfm

Pt(in w.g)

Throw (ft)

NC

cfm

Pt(in w.g)

Throw (ft)

NC

cfm

Pt(in w.g)

Throw (ft)

NC

cfm

Pt(in w.g)

Throw (ft)

NC

cfm

Pt(in w.g)

Throw (ft)

NC

cfm

Pt(in w.g)

Throw (ft)

NC

200 Ak=0.230

250 Ak=0.360

300 Ak=0.540

350

400

Ak=0.722

Ak=0.975

500 600 800 1000 1200 1400

49 62 75 99 124 150 175

0.017 0.026 0.033 0.054 0.083 0.123 0.175

1-3 2-4 2-4 3-5 4-6 5-7 5-7

<15 <15 19 21 29 36 41

92 115 138 184 230 276 322

0.016 0.023 0.031 0.051 0.078 0.116 0.165

2-4 3-5 3-6 5-7 6-7 6-8 7-10

<15 15 20 24 32 39 44

144 180 216 288 360 432 504

0.015 0.022 0.029 0.048 0.074 0.110 0.157

4-6 4-7 5-8 7-8 8-11 9-11 10-13

15 16 20 26 34 41 46

216 270 324 432 540 648 756

0.013 0.020 0.027 0.046 0.071 0.106 0.151

4-6 5-8 6-9 8-10 9-12 9-13 11-14

15 16 19 28 36 42 48

289 361 433 578 722 866 1010

0.012 0.019 0.026 0.044 0.068 0.103 0.146

5-7 6-9 7-10 9-12 10-14 12-16 17-18

15 16 19 30 38 44 49

390 488 585 780 975 1170 1365

0.012 0.017 0.025 0.043 0.067 0.101 0.143

6-8 7-10 8-12 11-14 12-16 13-18 16-20

16 18 20 31 92 46 51

RD-S/B

Cfm - Air volume in cubic feet per minute.

Face velocity in fpm

Throw values are based on teminal velocity of 100 & 50fpm

Pt - Total pressure in inches water gauge

NC - Noise criteria values are based on 10dB room attenuation

Ak - Area factor in square feet.



10

Return Round Ceiling Diffuser (Type - B)

150

cfm

Size

in mm

Face Velocity

in fpm400 500 600 800 1000 1200 1400

Ps (in w.g)

NC

cfm

Ps (in w.g)

NC

cfm

Ps (in w.g)

NC

cfm

Ps (in w.g)

NC

cfm

Ps (in w.g)

NC

cfm

Ps (in w.g)

NC

200

250

300

350

400

49 62 75 99 124 150

<15 15 19 21 29 36

92 115 138 184 230 276

<15 15 20 24 32 39

144 180 216 288 360 432

15 16 20 26 34 41

216 270 324 432 540 648

15 16 19 28 36 42

289 361 433 578 722 866

15 16 19 30 38 44

390 488 585 780 975 1470

16 18 20 31 92 46

175

0.011 0.010 0.013 0.029 0.047 0.074 0.105

41

322

0.010 0.011 0.015 0.031 0.052 0.080 0.112

44

504

0.011 0.012 0.017 0.034 0.055 0.085 0.118

46

756

0.012 0.013 0.018 0.036 0.058 0.089 0.123

48

1010

0.010 0.014 0.019 0.038 0.060 0.092 0.127

49

1365

0.011 0.015 0.020 0.039 0.062 0.094 0.130

51

RD-R/B

Ps - Negative static pressure in inches water gauge.

NC - Noise criteria values are based on 10dB room attenuation

Cfm - Air volume in cubic feet per minute.


EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Ordering Requisites

11

Standard Colour RAL9010Mill Finish MFOther Colour (RAL CODE)

1. Type

2.Neck Size:

3. Number Of Units In Numbers

4.Accessories

5. Colour

Example

Supply Round Diffuser - Type A RD-S/A

Return Round Diffuser - Type A RD-R/A

Supply Round Diffuser - Type B RD-S/B

Return Round Diffuser - Type B RD-R/B

Ø In mm

Foam Gasket F

RD-S/B 150 Ø mm F RAL 901075

1 2 3 4 5

Round Diffuser - Supply / Type B 150mm, 75 units with Butterfly Damper, with Foam Gasket, White RAL 9010.

Ordering RequisitesRound Diffusers

EXCELAIR Air Outlets | Technical Catalogue Round Diffusers | Notes

12

NotesRound Diffusers

All rights reserved.If you are not the right recipient, you should not disclose,copy,use or publicize the contents.

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EXCELAIR GD1000 SERIES Available in RAL 9010 & 9016 Colors.

All other colors are available on request.

Coyright

Tel: +971 4 3416337, Fax : +971 4 3416338P.O Box: 60270, Dubai, United Arab [email protected]

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Round Diffusers