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Gas Store > Gas Heating > Ventilation > Stadium Core Drill and Brick Type Ventilators >  Stadium BM720 Black Hole Brick Ventilator

Stadium BM720 Black Hole Brick Ventilator
Stadium BM720 Black Hole Brick VentilatorStadium BM720 Black Hole Brick VentilatorStadium BM720 Black Hole Brick Ventilator


Stadium BM720 Black Hole Brick Ventilator

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Price: £26.40 (£22.00 exc. VAT)

Quantity:

In Stock

Ref Code:BM720

BM720 - 70cm2 Effective 'Free Area'. Max: 21kW (71,500btu/h).
Rustic red double size airbrick 216mm x 152mm. Cavaity liner in two parts fixed together and with a continuous airway. Centre joint with cavaity drip. White inner grill. Reversible for both high or low level. Screw covers for flush fitting.


As outside wind pressure increases, a normal ventilator lets more air through causing annoying draughts. Inside the Stadium 'Black Hole" Ventilator Vortices are formed behind the internal blades as the incoming air is forced to change direction. The gap that the air is able to pass through narrows. As wind pressure increases, the vortices grow so reducing the total air flow, finally tumbling and slowing to a tricle, thereby cutting down annoying draughts.

However, when the heating appliance is operating, air is drawn throught the vent and actually speeds up within the constricted air flow between the vortices, thus maintaining the correct amount of air into the room or compartment to allow the fuel to burn efficiently and flues gases to escape. When the appliance is not working, incoming air is reduced to a minimum, even on windy days. The actual physical difference is that of air blown or drawn. The energy of the blown air (wind) is quickly dissipated by the restriction of the internal shape and the vortices while the drawn air will flow smoothly round the vortices.



Please note that the delivery status of this product is: In Stock

Free Delivery**
Royal Mail: items up to 1.5KG£3.95+Vat
Parcelforce 48 Hour* (Usually two working days)£5.75+Vat
Parcelforce 24 Hour* (Usually next work day)£8.50+Vat

* £6.00+Vat Surcharge will be added for orders from the Scotish Highlands and the Isle of man

** for orders over £100.00+Vat within the UK and Ireland

For delivery charges to Europe and the Rest of the World please click here.


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