changing a vent

bungaro79

have a vent in the front room but there is a noticable draft coming through it some days. it doesn't seem to have any way of closing so i'm wondering if i can just change it for a hit&miss vent or some other adjustable type. we have a gas fire in the room so i know we need to have ventilation of some sort but is it ok to have an adjustable one as long as i keep it open all the time bar when its really windy or cold??

shane0007

No gas fires MUST have non-closable vents.
You could change it to a baffled vent which will reduce draft.

bungaro79

thanks shane, are these available in a place like woodies or b&q or would i be better off going to a plumbing shop?? never heard of this type of vent, should this make a difference to the cold coming in to the room do you think??

shane0007

bungaro79 wrote: »

thanks shane, are these available in a place like woodies or b&q or would i be better off going to a plumbing shop?? never heard of this type of vent, should this make a difference to the cold coming in to the room do you think??

Yes they make a big difference.
You won't find them in the usual suspects.
http://www.gasproducts.ie/acatalog/Stadium_BM701_Black_Hole_Brick_Ventilators.html
Hamilton Gas Products.
Have a chat with your RGI to make sure the vent is sized correctly for the gas fire.
Also install a CO alarm in the room for safety.

bungaro79

we only got the gas fire before christmas and they gave us a co2 alarm. the guy who fitted the fire actually changed the vent so it must've been an adjustable one before that. having a look into the vent and it looks like theres a pipe going out to the outside so would this http://www.gasproducts.ie/acatalog/Stadium_BM418_127mm_Core_Drill_Ventilator.html be the one we're after?? and might be a stupid question but does the end in the photo go inside or out?!

shane0007

That one does not have baffles. The only one with baffles are the rectangular shaped ones as I have posted.

bungaro79

it says on the spec that there is an anti-draught baffle supplied so i thought that might make it viable?? you seem to know what your talking about shane so i think i'll follow your advice and get onto the rgi guy who installed the vent and ask him what he thinks seeing as he worked on it. thanks for you help

Dtp79

bungaro79 wrote: »

it says on the spec that there is an anti-draught baffle supplied so i thought that might make it viable?? you seem to know what your talking about shane so i think i'll follow your advice and get onto the rgi guy who installed the vent and ask him what he thinks seeing as he worked on it. thanks for you help

I'm pretty sure you're vent in your first pic is only 8,000 mm2. You need at least 10,000mm2 ( 100 cm )

shane0007

Dtp79 wrote: »

I'm pretty sure you're vent in your first pic is only 8,000 mm2. You need at least 10,000mm2 ( 100 cm )

How did you work that one out when you do not know the kw output or type of stove installed?

Dtp79

shane0007 wrote: »

How did you work that one out when you do not know the kw output or type of stove installed?

Thought it was a gas fire. The minimum ventilation needed is 10,000 isn't it?

shane0007

Dtp79 wrote: »

Thought it was a gas fire. The minimum ventilation needed is 10,000 isn't it?

Nnnoooooo, check your IS813!

Dtp79

shane0007 wrote: »

Nnnoooooo, check your IS813!

Yes but the new technical guidance book says gas fire minimum 10,000? I understand 813 is still the one to go by but I'd rather go larger than smaller

shane0007

Dtp79 wrote: »

Yes but the new technical guidance book says gas fire minimum 10,000? I understand 813 is still the one to go by but I'd rather go larger than smaller

The TGD is a direct reference to IS813. Minimum 10,000mm2 is for DFE's. Not all gas fires are DFE's!
In addition to that, the age of the building comes into the equation where an allowance of 3,500mm2 can be allowed for adventitious air for buildings built prior to 2007.

My point is never be to quick to give a calculated statement when not all the quantifiables are known. Thus my recommendation for the OP to seek advice from their RGI.

Dtp79

shane0007 wrote: »

The TGD is a direct reference to IS813. Minimum 10,000mm2 is for DFE's. Not all gas fires are DFE's!
In addition to that, the age of the building comes into the equation where an allowance of 3,500mm2 can be allowed for adventitious air for buildings built prior to 2007.

My point is never be to quick to give a calculated statement when not all the quantifiables are known. Thus my recommendation for the OP to seek advice from their RGI.

Ah yes of course but personally I'd never even factor in adventitous air. True I did jump the gun on the DFE. That was an assumption. Me, I always go with at least 10,000 as a starting point

Dtp79

But yes you are right Shane, the OP should get an RGI to asses the situation