Air Ventilation

Postby mblago » Wed Dec 17, 2008 5:15 pm

I have a 9kw basket type gas fire and have 100 sq centimetre air vent fitted to outside wall. The problem I have is that I want to have a new porch built which will cover up the air vent, would it be ok to have the same size air vent built in to the porch so there is a continous stream of air flowing from the lounge to the outside ?

many thanks in advance for your advice.

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Postby Steve the gas » Thu Dec 18, 2008 4:21 am

Hi Mike,

I would 'cos your vent is over large anyway if I've done the calcs correctly.
Steve the gas
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Postby gasmick » Thu Dec 18, 2008 9:13 pm

Hi ESSENTIAL GAS SAFTEY 4th edition states for D F E fires Unless otherwise stated in the manufacturers instuctions 100cm2 of permanent should be installed for all decoratve fuel effect fires up to 20kw(net)
it also states in the gas fires and space heater books (corgi) second edition
The purpose of the ventilation is not only to provide combustion air for for the appliance but to satisfy the requirements of the unrestricted flue (quote)
so you will need the same size vent again to the outside wall providing it is only passing through 1 further wall, any more than 1 will need the internall air vents to be 50% bigger than the outside one
No aventitious air is not to be taken into account for these fires

hope this helps mick
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Postby mblago » Mon Dec 22, 2008 5:31 pm

Thanks Mick, appreciate your help.
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