Systemair BIA Data Sheet

Air Distribution Products

BIA

Adjustable Displacement Diffuser

Data Sheet

2 / 12 | Variable Geometry Diffusers

Table of Contents

Description . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Ordering Code . . . . . . . . . . . . . . . . . . . . . . . . . 6

Technical Parameters . . . . . . . . . . . . . . . . . . . . . 6

Installation, Maintenance & Operation . . . . . . . . . . . . 10

Transport & Storage . . . . . . . . . . . . . . . . . . . . . . 10

Supplement . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Related Products. . . . . . . . . . . . . . . . . . . . . . . . 11

Good to know

Current information on all products is
available at design.systemair.com

Variable Geometry Diffusers | 3 / 12

Description

BIA is a variable geometry displacement/induction
hybrid diffuser, mainly intended for air supply in
comfort ventilation systems for industrial-, ofce-
and public halls.

Highlights

• Compact dimensions

• Precise adjustment of different discharge patterns

for heated and cooled air

• Pressure drop independent from the air discharge

mode adjustment

• Manual or motorized adjustment versions

• Easy and quick installation in elevation 0 m to 5 m

Product Types

• BIA-...-HC: Variable geometry displacement/induction

hybrid diffuser with manual geometry adjustment

• BIA-...-MC: Variable geometry displacement/induction

hybrid diffuser with continuous actuator for geometry
adjustment

Fig. 1: Air ow visualisation
Left: vertical discharge, heating mode
Right: horizontal discharge, cooling mode

4 / 12 | Variable Geometry Diffusers

Design

The diffuser casing is made from galvanized perforated steel sheet. A version with the casing from satin nish

stainless steel is also available for better protection in case of water condensation in spaces with higher humidity.

The air inlet with rubber gasket ts to the standard circular spiral ducts. The upper part with vertical slit perforation

permits the air discharge in vertical direction with higher face velocity (induction mode). The lower part with
perforation of circular holes permits the air in displacement discharge mode. The internal mechanism adjusts
the ratio between the induction and displacement air discharge. The positioning of the mechanism can be manual
or with electrical (AC 24 V) continuously positioning (DC 0 V … 10 V) actuator. The manual adjustment is possible over
longer distance by a rope bound to the adjustment pull chain, when the diffuser is installed in higher elevation.
The pull chain reaches app. 200 mm under the bottom of the casing. The mechanism assures pressure drop
independent from the adjusted position.

Controls

The diffuser type BIA-…-MC ais equipped by an actuator with AC 24 V power supply and continuous positioning
by the control signal DC 0 V …10 V.

Information about installation, maintenance and operation is available in the “UserManual_BIA” document
on

Systemair DESIGN.

Product Parts

Fig. 2: Components of BIA

4

1

2

3

6

5

Legend

1 Connection for spiral duct with rubber gasket

2 Perforation for vertical induction discharge

3 Perforation for horizontal displacement discharge

Platform with adjustment handle (BIA-...-HC)

4

or adjustment actuator (BIA-...-MC)

Pull chain for manual adjustment (BIA-...-HC),

5

reaches app. 200 mm lower than the casing bottom

6 Position arresting holder for manual adjustment (BIA-...-HC)