BESB
Ventilation box fan

The BESB box fan is a low-energy fan with backward-curved B impeller and sound-damping insulation.
BESB is available in 4 sizes - BESB250, 315, 400 and 500. BESB315, 400 and 500 are supplied with an airflow measurement outlet.
MOTORS:
All BESB box fans are equipped with an EC motor. Get an overview of the individual sizes below.
TEMPERATURE:
In normal operation, the BESB box fan tolerates temperatures up to 80 °C.
Combustion-gas fan
If there is a need for a certified combustion gas fan, we draw your attention to the FSB box fan, described under the product group Fire Safety
OUTDOOR VARIANT:
BESB can be ordered in an outdoor version (OD), which has the following features.
> Suitable for outdoor assembly
> Temperature range - tolerates hot air up to 200 °C

Product advantages
- Economy fan
- Low energy consumption
- Low operating costs
- Longer service intervals
- Low sound level
- Backward curved blades
References | Conditions |
---|---|
BESB25041EC2 | Conditions:> * I is the maximum current drawn in the entire regulation range – or full load current if this is greater> ** P1 is the maximum power drawn from the mains, where P2 is the power rating of the motor.> Specified data is at t = 20°C> Density = 1.2 kg/m3> Medium temperature: min. -12°C, max. +80°C> Ambient temperature: max. +40°C> Pressure ratio: < 1.11 |
BESB25041EC2OD, Outdoor | |
BESB25041EC2S | |
BESB31541EC2 | |
BESB31541EC2OD, outdoor | |
BESB31524EC2S | |
BESB40041EC2 | |
BESB40041EC2OD, outdoor | |
BESB40041EC2S | |
BESB50041EC2 | |
BESB50041EC2OD, outdoor | |
BESB50043EC | Conditions: * I is the maximum absorbed current throughout the control range - or the full load current if this is larger ** P1 is the maximum absorbed power from the mains supply, where P2 is the motor's nominal output. Stated data are for t = 20°C Density = 1.2 kg/m3 Gas temperature: min. -12°C, max. +80° C Ambient temperature: Max. +40° C Pressure ratio: < 1,11 other points in acc. with EC327/2011 - see product instructions |
BESB50041EC2S |
References | Max. Total efficiency (A-D) (%) | Ventilation energy class - Average climate | Efficiency level requirements | ECO efficiency level during optimal operating point | EC motor | Nominal speed (RPM) | Power supply | Overload protection | Engine power (kW) |
---|---|---|---|---|---|---|---|---|---|
BESB25041EC2 | 68,4 |
64, N(2015) |
96,8 |
EC motor with integral VSD |
1400 |
Integrated in motor control |
0,18 |
||
BESB25041EC2OD, Outdoor | 68,4 |
64, N(2015) |
96,8 |
EC motor with integral VSD |
1400 |
Integrated in motor control |
0,18 |
||
BESB25041EC2S | 68,4 |
Ja |
64, N(2015) |
96,8 |
EC motor with integral VSD |
1400 |
1x230 - 50 Hz |
Integrated in motor control |
0,18 |
BESB31541EC2 | 69,0 |
64, N(2015) |
92,8 |
EC motor with integral VSD |
1400 |
Integrated in motor control |
0,37 |
||
BESB31541EC2OD, outdoor | 69 |
64, N(2015) |
92,8 |
EC motor with integral VSD |
1400 |
Integrated in motor control |
0,37 |
||
BESB31524EC2S | 69 |
64, N(2015) |
92,8 |
EC motor with integral VSD |
1400 |
Integrated in motor control |
|||
BESB40041EC2 | 71,6 |
64, N(2015) |
95 |
EC motor with integral VSD |
1435 |
Integrated in motor control |
0,75 |
||
BESB40041EC2OD, outdoor | 71,6 |
64, N(2015) |
95 |
EC motor with integral VSD |
1435 |
Integrated in motor control |
0,75 |
||
BESB40041EC2S | 71,6 |
Ja |
64, N(2015) |
95 |
EC motor with integral VSD |
1435 |
1x230 - 50 Hz |
Integrated in motor control |
|
BESB50041EC2 | 71,5 |
64, N(2015) |
89,6 |
EC motor with integral VSD |
1420 |
Integrated in motor control |
1,1 |
||
BESB50041EC2OD, outdoor | 71,5 |
64, N(2015) |
89,6 |
EC motor with integral VSD |
1420 |
Integrated in motor control |
1,1 |
||
BESB50043EC | 74,6 |
64, N(2015) |
89 |
EC motor with integral VSD |
1757 |
Integrated in motor control |
2,2 |
||
BESB50041EC2S | 71,5 |
Ja |
64, N(2015) |
89,6 |
EC motor with integral VSD |
1420 |
1x230 - 50 Hz |
Integrated in motor control |
Conditions:
- I is the maximum absorbed current throughout the control range - or the full load current if this is larger
- P1 is the maximum absorbed power from the mains supply, where P2 is the motor's nominal output.
- Stated data for for t = 20°C
- Density = 1.2 /m3
- Values are based on the use of a transition piece equivalent to OGSR
- Gas temperature: min. -12°C, max. +60° C
- Ambient temperature: Max. +40° C
- Pressure ratio: < 1,11
- other points in acc. with EC327/2011 - see product instructions
The box fan can be mounted in different positions, however, space for insulating the ducts must be taken into account. In installation options B and D, with the door facing upwards, special fittings must be used to hold the door (accessory). The box fan should not be screwed onto the supporting base. The base must be stable and vibration free, with no sagging. The outdoor model can be installed according to options A and B.




References | A (mm) | B (mm) | C (mm) | G (mm) | E Ø (mm) | Weight (kg) |
---|---|---|---|---|---|---|
BESB25041EC2 | 785 |
625 |
325 |
800 |
250 |
52 |
BESB25041EC2OD, Outdoor | 785 |
625 |
325 |
800 |
250 |
52 |
BESB25041EC2S | 785 |
625 |
325 |
800 |
250 |
52 |
BESB31541EC2 | 785 |
675 |
355 |
800 |
315 |
57 |
BESB31541EC2OD, outdoor | 785 |
675 |
355 |
800 |
315 |
57 |
BESB31524EC2S | 785 |
675 |
355 |
800 |
315 |
57 |
BESB40041EC2 | 895 |
775 |
390 |
800 |
400 |
73 |
BESB40041EC2OD, outdoor | 895 |
775 |
390 |
800 |
400 |
73 |
BESB40041EC2S | 895 |
775 |
390 |
800 |
400 |
73 |
BESB50041EC2 | 990 |
860 |
425 |
850 |
500 |
88 |
BESB50041EC2OD, outdoor | 990 |
860 |
425 |
850 |
500 |
88 |
BESB50043EC | 990 |
860 |
425 |
850 |
500 |
91 |
BESB50041EC2S | 990 |
860 |
425 |
850 |
500 |
88 |
References | Minimum airflow | Max. airflow (m³/h) |
---|---|---|
BESB25041EC2 | 350 |
2260 |
BESB25041EC2OD, Outdoor | 350 |
2260 |
BESB25041EC2S | 350 |
|
BESB31541EC2 | 570 |
3590 |
BESB31541EC2OD, outdoor | 570 |
3590 |
BESB31524EC2S | ||
BESB40041EC2 | 950 |
6000 |
BESB40041EC2OD, outdoor | 950 |
6000 |
BESB40041EC2S | ||
BESB50041EC2 | 1180 |
7300 |
BESB50041EC2OD, outdoor | 1180 |
7300 |
BESB50043EC | 1330 |
10800 |
BESB50041EC2S |
References | Frequency (Hz) | Max. current (A) | Voltage (V) | Max. power | Engine power (kW) |
---|---|---|---|---|---|
BESB25041EC2 | 50 |
1,2 |
1x230 |
0,18 |
|
BESB25041EC2OD, Outdoor | 50 |
1,2 |
1x230 |
0,18 |
|
BESB25041EC2S | 1,2 |
0,17 |
0,18 |
||
BESB31541EC2 | 50 |
2,2 |
1x230 |
0,37 |
|
BESB31541EC2OD, outdoor | 50 |
2,2 |
1x230 |
0,37 |
|
BESB31524EC2S | |||||
BESB40041EC2 | 50 |
4,5 |
1x230 |
0,75 |
|
BESB40041EC2OD, outdoor | 50 |
4,5 |
1x230 |
0,75 |
|
BESB40041EC2S | |||||
BESB50041EC2 | 50 |
8,5 |
1x230 |
1,1 |
|
BESB50041EC2OD, outdoor | 50 |
8,5 |
1x230 |
1,1 |
|
BESB50043EC | 50 |
3,8 |
3x400 |
2,2 |
|
BESB50041EC2S |
References | Ventilation energy class - Average climate |
---|---|
BESB25041EC2 | |
BESB25041EC2OD, Outdoor | |
BESB25041EC2S | Ja |
BESB31541EC2 | |
BESB31541EC2OD, outdoor | |
BESB31524EC2S | |
BESB40041EC2 | |
BESB40041EC2OD, outdoor | |
BESB40041EC2S | Ja |
BESB50041EC2 | |
BESB50041EC2OD, outdoor | |
BESB50043EC | |
BESB50041EC2S | Ja |
BESB box fans are made from Aluzinc® AZ185 class C4 in accordance with EN/ISO12944-2 and insulated with 50-mm mineral wool.
As standard BESB can handle a gas temperature of up to 80°C, but in an OD version can withstand temperatures right up to 200 C.

The ventilator impeller is a B-impeller made from cast aluminium.
It has backward curved blades, thus ensuring low energy consumption and the further advantage that less dirt is attracted, with impaired impeller efficiency as a result.

The spigots on BESB have rubber gaskets, with a transition piece on the extract side specially developed for minimum pressure drop.

To minimise noise and vibration, the box fan is fitted as standard with efficient vibration dampers mounted on brackets.

The BESB box fan is mounted with split hinges, which enable the door to be removed for installation and servicing, even in very confined conditions or for transport to difficult locations.

The BESB box fan is designed to transport air with an air humidity of less than 80% RH.
BESB is available in a special OD variant with a condensation outlet for air with over 80% RH.

If there are problems moving the BESB box fan in one piece, it may be ordered in a SPLIT version.
- The box fan must be assembled by an approved EXHAUSTO fitter
- The box fan must be tested before the fitter hands over the fan
