outside wood boilers

Still the best solution for burning wood is to have massive heat storage which allows fast and clean burns. Russian or masonry fireplaces were used in this country in the 1600s. Modern designs could be even better with more efficient handling of secondary air.

Another way which used to be advertised is to bury the outdoor stove in a massive sand pile containing copper water coils buried in the sand.

It just makes no sense to squander most of the heat in the wood by throwing it away as smoke and creosote.

If I were to design an outdoor wood boiler I would design it to use wood chips instead of logs, that way a hopper could be used or maybe an auger feed. Air and feed could be precisely controlled in a well insulated fire box for very clean and efficient combustion. A range of heat output would also be possible.

The boiler would be of Scotch Marine fire tube design.

The extra expense of chipping the wood would be more than made up for by increased efficiency. It is even possible to get chips free in some counties that just want to get rid of them. Some landscapers even pay to get rid of them. There must be mountains of chips from the storm last week.

Most of the wood boilers I have seen have been designed by people who are good at metal fabrication but know nothing about combustion. If they did they would not be building the abortions they do since it is not possible, given the fuel form selected to have anything but crap as a result.

Wouldn't wood chips require a massive amount of 'dry' storage space?

lsayre wrote:Wouldn't wood chips require a massive amount of 'dry' storage space?

Good point which I did not consider.

I don't know if it is true but it seems logical that chips would retain more water from rain than logs. Wet wood whether in log form or chips should never go into the combustion chamber. The hopper design could be designed to dry the wood chips before entering the fire box with a certain loss of efficiency.

Wood sheds were a common feature when wood was a more common fuel than now. I think that chips would store more compactly than logs though I am not sure. Dry fuel no matter what kind is better than wet.

One of those steel frame canvas covered structures would be ideal. Double the cords of logs takes a lot more space.

I used to burn this much wood in one year in my Heatmor 200ss.

Now I burn less than two of these.

It looks like you could be killed just going near that pile of logs. Working through that pile you were either in a lot better shape or half dead.

franco b wrote:It looks like you could be killed just going near that pile of logs. Working through that pile you were either in a lot better shape or half dead.

I ended up climbing up on top and cutting them up. I started out with the tractor pulling them off but when one log flipped as it came down and missed the tractor by about a foot I stopped.

First time I have seen a wood rack made from full size trees.

From what I have been hearing, theres a boiler thats currently being tested that burns old hay, grains, wood chips, etc. that are at 35% moisture or under. Its very efficient, and would utilize waste for heat. Sounds ideal for tree services, farmers, etc. Carnage, I couldn't imagine burning that amount of wood. Last year our 6.5 cords, we had about 3" of attic insulation. Theres now 14" of cellulose and the attic has been airsealed. I figure we should be around the 5 cord mark hopefully this winter.

I had 6" of insulation in the attic. I've added another 12" on top of that. All 48 windows have been replaced along with 3 of the 5 outside entry doors. Soooo I'm still working on it.

Yea, but by God you've got a big chunk out of it.

cArNaGe wrote:I used to burn this much wood in one year.

Now I burn less than two of these.

DITTO !!!