Tarm boiler solo 40

[geordie]

Any secrets to loadiing the boiler? Often wood gets caught/blocks the opening at the
bottom of the firebox, hence no burn. Sometimes poking it works, but it can take
lots of time that I don't have in the morning.

 

[Nofossil]

Any secrets to loadiing the boiler? Often wood gets caught/blocks the opening at the
bottom of the firebox, hence no burn. Sometimes poking it works, but it can take
lots of time that I don't have in the morning.

Welcome to the forum and the boiler room, geordie. Nice to have another Vermonter here. Can't answer your question specifically, since I don't know the details of the Tarm internals, There are several Tarm owners here, so I expect someone will chime in. For my part, I've had good luck always loading a mix of sizes. All big pieces doesn't burn as well and might contribute to what you're seeing.

 

[Reggie Dunlap]

Yup, I have the same problem sometimes. The tunnel gets blocked either with wood or coals and gasification stops. I throw a couple of pieces in sideways sometimes and it creates a bridge across the tunnel, but it dosn't always work.

I thought about building a metal cage of some sort but I don't know what would hold up to those temps.

 

[bbb123]

I occasionally have a bridge develop when the center of my pile burns out. Ive never had the tunnel "plug" up if you keep It gasifiying it blows any ash and even coals to the bottom of boiler. The only time I clean out the curved chamber is when I clean out the top chamber and all the ashes fill it. The bridge problem seems to happen when I stick a piece of wood just a little to long so I keep them for a small load and I can turn them at an angle. After reading how other people start there gasifiers I have changed my start up procedure.

I use the 1/3 of a fire starter light that let it get burning just to the side of the nozzle.
2 pieces easy to light (popular,pine etc) over the top of the starter and fill rest with about 1/2 a load.
Close top door, open bypass, open bottom door, turn on fan.
Go put pot of coffee on 3-5 minutes go back and check.
Should see flames over wood if not smotherd starter.
Once flames are over wood shut bypass and usually mine gasifys immediatly.

 

[EricV]

I occasionally have a bridge develop when the center of my pile burns out. Ive never had the tunnel "plug" up if you keep It gasifiying it blows any ash and even coals to the bottom of boiler. The only time I clean out the curved chamber is when I clean out the top chamber and all the ashes fill it. The bridge problem seems to happen when I stick a piece of wood just a little to long so I keep them for a small load and I can turn them at an angle. After reading how other people start there gasifiers I have changed my start up procedure.

I use the 1/3 of a fire starter light that let it get burning just to the side of the nozzle.
2 pieces easy to light (popular,pine etc) over the top of the starter and fill rest with about 1/2 a load.
Close top door, open bypass, open bottom door, turn on fan.
Go put pot of coffee on 3-5 minutes go back and check.
Should see flames over wood if not smotherd starter.
Once flames are over wood shut bypass and usually mine gasifys immediatly.

Yep, I do almost exactly the same. I turn the bottom 2 pieces a bit sideways then a few more pieces. Then I add 1/3 of a starter stick. Then I load the chamber to the top, but I use my normal wood, nothing else like kindling, etc. Light the starter stick, close the top door, open the bottom and she'll take off pretty good. I Then close the bottom door after a bit (time seems to vary with wood, but 10 minutes seems to be plenty) shut the bypass and turn the blower on.

Final step, very important, don't skip

Return to the easy chair and watch the fuel truck go by my house to the guy next door.

This works 90% of the time on the first try without any fiddling.

Eric

 

[55Razor]

Geordie, I haven't had the situation where the refractory slot got plugged enough to prevent gasification. Sometimes after loading I can see where this area is covered and it struggles to get started again, but always does after a couple of minutes. I have had it where the wood load would "bridge-up" and not be able to fall down into the coal bed, so the coal bed burns away and gasification basically stalls out. Usually stirring everything around gets it going again. I think this may happen because one, I load a piece the same length as the firebox, and it wedges itself in, and/or two, I found that if I have a more flat, oval piece of wood say from the outside split of a large block, I need to lay it in on the flat rather than on edge. I suspect on edge it tries to flop down, and gets hung up. In my case you can see both are due to operator-error! Hope this helps.

 

[jebatty]

Query for those who can provide some objective measurement of performance: what effect, if any, does bridging have on the total heat output over the course of a full burn?

Both EKO and Tarm users have mentioned "bridging" and a number of ways to reduce bridging have been suggested. I experience this also (Tarm Solo Plus 40), and when I notice it it, I too mess the load up a bit to collapse the bridge. Yet, I know I could not have noticed this every time, and in fact, I have burned full loads without ever checking the progress. So I suspect bridging has occurred and collapsed on its own without intervention. No matter what during the burn, the end result is a bed of fine ash.

It is clear that during a burn, flue temp drops during the bridge, and rises when the bridge is collapsed. But does bridging really reduce overall efficiency or heat output of the full burn? Does bridging really merit any serous attention?

Actual data would be appreciated. Thanks.

(a copy of this post is being place in both the EKO and Tarm bridging threads)