New to secondary burn

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Nov 23, 2005
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I just installed a used 5 yr old VC Aspen last night. I replaced a 1981 Coalbrookdale Much Wenlock Coal/Wood unit.
I was surprised to see that the Aspen manual doesn't list recommended stove top or stove pipe temps. They merely state that if the "stove glows red its to hot".

It seems to work well but I have a few question about the secondary burn aspect. The stove is top vented, piped into aprox 30' of stainless 6" liner in an interior chimney with a well sealed top and cap. I am running it right now and have been for about 20 Min with a Magnetic temp reading of 400 about 10 " from the stove top on an Elbow. I still see a fair amount of smoke coming from the chimney top. I thought one of the great things about secondary burn was almost no smoke? Or does this only kick in when you are at glowing coals not flames? I do see the secondary device working, three horizontal pipes at the top of the firebox with the many holes in them burning like a broiler on a gas oven.

Also the manual doesn't say anything about calibrating the thermostatically controlled primary air inlet. I also burn in an Efel coal unit and that manual lists a detailed procedure for adjusting the thermostatically controlled air supply. I wonder if VC thinks this is beyond the average homeowner?
 

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Do you have proper clearances to combustibles? The stove looks close to the wall, and is that a wood table you have it sitting on :bug: ????
 
Yes it is sitting on a wood table..... soaked in gasoline. No those are 8"' Steel I Beams. and the oak side table off to the side is 4' away. The photo makes it look a lot closer. The back wall is 12" away, the manual says 9"' is acceptable Heat shield and protected surface with 1" air space.
 
I just installed a used 5 yr old VC Aspen last night. I replaced a 1981 Coalbrookdale Much Wenlock Coal/Wood unit.
I was surprised to see that the Aspen manual doesn't list recommended stove top or stove pipe temps. They merely state that if the "stove glows red its to hot".

It seems to work well but I have a few question about the secondary burn aspect. The stove is top vented, piped into aprox 30' of stainless 6" liner in an interior chimney with a well sealed top and cap. I am running it right now and have been for about 20 Min with a Magnetic temp reading of 400 about 10 " from the stove top on an Elbow. I still see a fair amount of smoke coming from the chimney top. I thought one of the great things about secondary burn was almost no smoke? Or does this only kick in when you are at glowing coals not flames? I do see the secondary device working, three horizontal pipes at the top of the firebox with the many holes in them burning like a broiler on a gas oven.

Also the manual doesn't say anything about calibrating the thermostatically controlled primary air inlet. I also burn in an Efel coal unit and that manual lists a detailed procedure for adjusting the thermostatically controlled air supply. I wonder if VC thinks this is beyond the average homeowner?


I haven't owned an Aspen, but the Jotul 602 would be smoke free once the stove running over about 400 degrees and the wood had charred thoroughly. Typically that was about 30 minutes after startup. These box stoves can really put out the heat and the 602 would take off if one didn't watch it closely. I would typically reach a peak, stovetop temp of about 650 with a wood load, though at times it got over 800. Good to hear that you have generous clearances.

At what stage are you seeing smoke? Throughout the entire burn or just at the beginning? I'm wondering if you are seeing steam or smoke. Are you seeing darker grey smoke, or white smoke? How is the wood? Very dry or almost dry, but still a little damp in the core?

FWIW, after the wood was charred, I'd close the stack damper. We had good draft and the stove temp would rise another 25-50 deg. after closing the damper.
 
the smoke is mostly as the box is still filed with flames. Once the wood becomes coals the smoking stops.
I did hit 700 on the stove top and backed it off a little. I wish he manual had recommendations for stove top temps.
Right now I have a deep bed of coals Magnetic pipe temp of 300 Magnetic stove top of 600 and no smoke at all from the Chimney top.
I guess this is the way it should be.

The nearest combustible surface is just barely warm to the touch
 
the smoke is mostly as the box is still filed with flames. Once the wood becomes coals the smoking stops.
I did hit 700 on the stove top and backed it off a little. I wish he manual had recommendations for stove top temps.
Right now I have a deep bed of coals Magnetic pipe temp of 300 Magnetic stove top of 600 and no smoke at all from the Chimney top.
I guess this is the way it should be.

The nearest combustible surface is just barely warm to the touch

If you have that deep bed of coals, and add another log, you should see flames within about 10 seconds, and the secondary should kick in nearly at the same time. At that kind of burn you should not see any smoke that is the result of unburned gasses.
 
the smoke is mostly as the box is still filed with flames. Once the wood becomes coals the smoking stops.
I did hit 700 on the stove top and backed it off a little. I wish he manual had recommendations for stove top temps.
Right now I have a deep bed of coals Magnetic pipe temp of 300 Magnetic stove top of 600 and no smoke at all from the Chimney top.
I guess this is the way it should be.

The nearest combustible surface is just barely warm to the touch

Sounds like it's burning well. I'd shoot for a stovetop temp of 450-650 degrees.

If you have time, take another shot of your installation and post it in the pictures section. Try to get it at an angle that shows off the I-beams. That is a novel approach. Pretty cool idea. Though knowing me, I'd bump into one of them in middle of the night.
 
I would be cautious of that set up on the beams. I know my stove has actually walked a little after several firings and cool downs. It would be a shame to have it unbalance itself that way. NO expert but that would concerm me a bit. One could always build a lip around the beams and weld them together with a cross section so they would be one solid unit. MY $0.02
 
I could strap them together. I ran a coal stove this way for two years without problem. I did get this on Ebay, the seller delivered for free, and helped me put it in its current spot. because he said he got more for it than he thought he would. I know i could have gotten brand new for about 300 more. he also said any problem and he would take it back. So far so good
 
Congrads on your new stove [email protected] , that should help keep the gas man away.

I few things i have noticed , looks like your pipe going horizontal is running down hill ? Maybe I'm seeing things ........a horizontal run of pipe should be going up hill 1/4" per foot of length to keep proper draft.

The steel I-beams is a very clever idea ......... I would also have them hooked together or bolted to the floor.

I photo shopped your pic's for detail.
First pic is the horizontal pipe run i had mentioned.
 

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I came very close to buying a VC Aspen. It looks like a nice little stove. I ended up deciding on the Jotul 602. Everything that was posted above by BeGreen is right on. I have found that to get decent heat for my little Jotul it needs to be hot - say 600+. And once I also saw over 800 F on my indicator. But not on purpose.

Good luck and I would be interested to hear how it goes for you and the Aspen. What we need here in CT is some cold weather.

regards, Mike
 
I'd also be interested in how the aspen burning goes. It seems like a nice little stove, but in this category the 602 seems the standard. The idea of the firebrick interior seems like a good idea.

I'd consider one for my basement room in the future. Odd thing is that I'm sure the chimney would cost like 1.5 x the cost of an aspen.
 
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