On 11 Mar 2006 16:04:52 -0800, wrote:

speaking from experience Dave you would be bunging wood in every half
hour and still getting little heat if you have a back boiler in it.

I suspect that you are expecting too much from the back boiler, to supply
15kW of heat you are going to be bunging wood in fairly often, the energy
has to come from somewhere. You also mention pumped rather than gravity,
I can see that overcooling the fire as well.

I'll be putting in a wood burner at some stage here with a boiler but I
don't expect it to heat the whole house (our 38kW oil jobbie struggles
when it's -5C and blowing a gale) but it should be able to keep the chill
out and will be completely passive, no pumps or motorised valves.

To answer the other matter, if the stove is placed within the chimney
place rather than outside it, a lot of the heat just goes up the
chimney.

Ah an open based chimney, that seems like a bad installation to me. A
properly installed wood burner really needs an insulated flue to stop the
gases condensing inside the chimney. This implies that the base of the
chimney is "sealed" from the room.

another common mistake many people make is to light the fire on a grate
and clear out the ash every day. I burn wood on a bed of ash and only
clear it out when it rises above the front plate,

Agreed wood burns best on a bed of ash. Coal on the other hand doesn't.
I've just cleaned out our open fireplace after burning the cut up remains
of two old sofas. Lots of heavy wire staples, castor sockets, screws etc
left on the grate enabling a nice bed of ash to build up. Fire burned
great on that, doesn't now. B-(

--
Cheers
Dave. pam is missing e-mail