AJH wrote:
On Fri, 13 Oct 2006 00:11:39 +0100, The Natural Philosopher
wrote:

Pretty hard to have a stove that WON'T do 5Kw.

I think the little Jotul 602 that heats this house if 5kW

Anyway once you exceed that you need 550mm^2 of dedicated air supply
per additional kW. In the pass there was a provision for supplying
some of this by infiltration air but I suppose draught proofing means
that isn't allowed now,

I'd day our open fires peak at about 50Kw or more,

That's an interesting one because part J only caters for solid fuel
fires up to 50kW. The requirement for air supplies for such a device
could make such a fireplace very draughty.


Oh, it is. We have a couple of 9" square gratings in it, going to 4"
pipes to the underfloor cavity. However the two fires in question are
seldom both lit and the room is open plan ish with a central chimney and
the fires are back to back, and the rooms are not sealed from her rooms..

I guess the direct ventilation is about 15,000 mm^2

So enough for about 8KW 'by the rules'

or 11KW if one fire only is lit.

In practice they work well and draughts are confined just to the area
around the fire base. And when I say 'peak' I men 'peak. I.e. thats what
happens when you get a lot of wood just dry enough and it all goes up
fairly fast. In practice its usually around 3-5KW.




AJH