New Woodshed (and Boiler)

[SuperSpy]

I'm still finishing (and cleaning) up from the installation, but eventually I'll have it probably half full of random hardwood, if it ever stops raining.

Shed is about 7'x6'x7' with about a foot roof overhang. I'm debating putting sides on it or just adding a few more horizontal boards to keep the stacks in.

Boiler is a Central Boiler Classic Edge 350 in stainless steel which is now doing duties feeding the hot water heater and forced air furnace.

 

[Jags]

Any estimate on consumption of wood for the cold michigan winters?

 

[SuperSpy]

Rough estimate in comparison to the old (non-EPA/non-catalytic) wood burning forced air furnace that it replaced is probably 1/3 of the old unit or maybe even better. Also 1000% lower chance of chimney fire burning down the 100+ year old farm house.

I wasn't very careful counting the firewood usage last winter (my first winter in the house/burning wood) so I'm not sure of absolute cordage. Plus I wasn't very prepared last year so my wood was still a bit high in moisture. This year will be much better, although since I get mostly red oak it will still be a little on the high moisture side due to the long seasoning times.

Hopefully by next summer I will be in front of my consumption enough to have a full winter's worth of seasoned wood available.

 

[Jags]

Does your new boiler have re-burn technology in it (sorry, not a boiler model wonk)?

 

[SuperSpy]

Yeah, it's a gasification boiler. The boiler has 2 rails on the sides of the firebox near the bottom to keep the fire lit, then another rail coming out of the front down the center of the firebox that blows down into a hole where the gasses are burned in a secondary chamber, which then vents up out the back through an exchanger to the chimney.

Short vid of it in action:


It smokes like a train for about 15 seconds after you load it, and just a little (mostly steam) when it's working on a fresh charge, especially if the wood is wet. When it's in it's high powered burn mode, however basically nothing comes out of the chimney.

 

[BoiledOver]

Looks like you have set yourself up very well. If the dealer did not stress the fact to use thoroughly seasoned fuel, hear it now. Wood gasification boilers do very, very well with Moisture Contents below 17%. Anything above twenty percent MC and the efficiency will begin to suffer quickly in relation to the increase in MC.

Here is a link to a brochure concerning the OP's unit, pretty slick rig. https://centralboiler.com/pdf/brochure-classicedge.pdf

Is there access to the vertical heat exchanger tubes for cleaning purposes? In our indoor gasification units, it is standard procedure for many to clean these tubes several times or more per heating season.

Best wishes for the heating season.

 

[SuperSpy]

The original model had a set of screws in the back of the firebox you could undo and pull a panel off revealing the heat exchanger.

My unit is a new revision that puts this panel on the outside of the unit on the back which makes it much easier to clean. They really aren't tubes though, they are just a wall of triangular seams (like /\/\/\/\) that you can just clean directly with a normal brush.

I haven't had to clean it yet, so not sure how bad it would be, but by the looks of the secondary chamber so far there won't be much cleaning needed.

 

[maple1]

The more often you clean it, the better it will do. Even a thin layer of fly ash can lessen heat transfer. I try to get in the habit of brushing my tubes every Sunday, during the heating season. Only takes me 5 minutes. I haven't had a brush in my chimney since I got the new boiler running, heading into my 6th season with it now. That is one part I REALLY like.

EDIT to add - you will see big performance gains, the drier your wood gets. My first year, it wasn't too bad but still not optimum. At the end of that year, I had NO wood left - due to other things happening. So been playing catch up ever since and using 'non-optimum' wood while doing that. Last year was really good - this year should be about as good as I can get since I am finally burning wood that has had 2 full years of seasoning. Feels good to have a year in the basement ready to go plus almost another 3 years stacked in the yard. Now looking forward to seeing how much wood I will have left over in the basement after this winter.

 

[SuperSpy]

Yeah mine was really bad when I first started burning in it because it wasn't really cold yet so it was just serving the hot water heater. I ran it anyway because I wanted to get the hang of it before I really needed it. So it spent a lot of time in idle mode with the air supply cut off. Now that I'm heating (Michigan went from 75f to 30f in 2 days), it is much improved and burning a lot more cleanly, even with my wetter than optimal wood.

This should be the last year of me having poorly seasoned wood though as I've gotten enough around this year that by next year I should have wood that has been sitting for at least a full year, maybe two depending on how little this new unit burns.