Non-return damper

Non-return damper

In intermittent-operation ventilation systems, if the fan is stopped, the backdraft damper will prevent outside air from entering the building and the resulting energy losses.
Non-return damper
Non-return damper
The non-return damper consists of a steel body and two spring-loaded flaps that close when the fan stops running. In this way, the ductwork is isolated from the ingress of outside air and from thermal disturbances.
Non-return damper

The + products

  • energy savings and comfort when the fan is switched off,
  • easy to install.

The flaps of the backdraft damper are spring-loaded to close as soon as the fan has stopped running.

  • steel body,
  • aluminium flaps,
  • in-mould seal between the damper and the duct (double seal above diameter 250) and between the closed flap and the damper body.
  • slots simply into a circular duct,
  • when mounted vertically, the flaps must open upwards.
  • ensure the direction of assembly is correct so that the flaps are in the open position when the fan unit operates.
Insulation material
References L1 (mm) L2 (mm)
11094680 - Backdraft damper Ø 80

40

42

11094681 - Backdraft damper Ø 100

40

51

11094682 - Backdraft damper Ø 125

51

65

11094683 - Backdraft damper Ø 150    
11094684 - Backdraft damper Ø 160

68

82

11094685 - Backdraft damper Ø 200

74

95

11094686 - Backdraft damper Ø 250

120

145

11094687 - Backdraft damper Ø 315

160

178

11094688 - Backdraft damper Ø 355

160

198

11094689 - Backdraft damper Ø 400

160

223

Products and accessories references

  • Backdraft damper Ø 80
    Backdraft damper Ø 80
    11094680
    43,20 (without VAT)
  • Backdraft damper Ø 100
    Backdraft damper Ø 100
    11094681
    43,70 (without VAT)
  • Backdraft damper Ø 125
    Backdraft damper Ø 125
    11094682
    45,20 (without VAT)
  • Backdraft damper Ø 150
    Backdraft damper Ø 150
    11094683
    47,80 (without VAT)
  • Backdraft damper Ø 160
    Backdraft damper Ø 160
    11094684
    47,80 (without VAT)
  • Backdraft damper Ø 200
    Backdraft damper Ø 200
    11094685
    73,30 (without VAT)
  • Backdraft damper Ø 250
    Backdraft damper Ø 250
    11094686
    89,90 (without VAT)
  • Backdraft damper Ø 315
    Backdraft damper Ø 315
    11094687
    123,00 (without VAT)
  • Backdraft damper Ø 355
    Backdraft damper Ø 355
    11094688
    168,00 (without VAT)
  • Backdraft damper Ø 400
    Backdraft damper Ø 400
    11094689
    185,00 (without VAT)