wood fired boiler combustion chamber shapes

[bryanf]

We are building (for fun and education) a wood fired hot water boiler. We are planning a brick lined fire box of about 4 feet by 4 feet by 8 feet long with forced air. I wondered if anyone had any thoughts on different shapes or air inlet locations that might make for a more efficient combustion chamber. This will burn chunks and logs rather than sawdust or pellets and will have a 4 pass heat exchanger for the exhaust gases. Also the water side will be open so we don't build pressure. Any suggestions or tips would be great. Thanks

 

[a31ford]

I see that this is an old post, but will reply, hoping it sends you an e-mail, 4x4x8 appears to be quite huge ? doesn't it ?? Is this in ft. meters or what ? My son and I are trying a firebox design (downdraft). I don't know if the forum allows conversation(s) so here's my e-mail a31ford@mts.net Lets talk !

G.