New to me Woodstock Keystone - creosote in the fire box

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esparent

New Member
Nov 5, 2019
22
Vermont
Hello, first post here.

I have a new to me Keystone that I'm learning to run and have a couple questions. A bit about the stove:
-It's a 2011
-Just replaced the combustor and it's gasket
-Unfortunately after getting it home I noticed that there was some warping of the bypass cover and combustor pan. I've been in contact with Woodstock and Jeff Gibbs (former builder for Woodstock), and have replaced the bypass cover, it's gasket, and now get a good seal with the cover. The combustor pan will likely get replaced next summer.
-I've only been running the stove about a week now so I'm still in the learning curve.

So far I'm getting pretty good burn times and the combustor seems to be working quite well. White smoke or no smoke from the chimney, rising temps after engaging the CAT, and visible glow at times. I usually load the stove twice a day, once before bed and once before I leave for work in the morning, sometimes more on the weekend. I've been noticing that if I let it die down all the way, stove temp maybe 100-150 and very little coals left that the inside of the stove, primarily the back lower corners and near the door have some shiny black creosote. Is this normal? Is there anything I can do to prevent it?
The stove is set-up top-venting, near straight to a 45 degree turn through the wall, then 90 degrees straight to the top. Straight vertical run is maybe 25' so I feel I have good draft. I checked the chimney tonight and it appears pretty clean, just a bit dusty, no shiny creosote anyway.

Lastly, I'm a fairly experienced wood burner but never used a catalytic stove before. Always had a wood stove growing up and in this house for the past 3 years we've run a VC Encore 1450 non-cat.

Any input, tips, or advice is greatly appreciated!
 
When you smolder wood, like you do in a cat stove, some of that is going to condense in the box. As long as the cat is working, and you don't see much creo in the chimney, you're good. I don't worry about the creo in the box too much, but once in a while I'll pop some of it off with a putty knife so that radiation can heat the stone better. That said, areas where there is creo might be cooler due to leaking air. I noticed that on the Keystone and Fireview, you will see white, clean margins on cemented seams where the creo is burned off by leaking air, while areas further from the seams will have more creo condensed where the air leak is cooling the stones nearby.
But the areas you mention are going to be cooler from air coming in near the door, or from the hole in the back of the ash pan housing, which comes up through the ash grate in the back (unless you elect to let ash get deep on top of the grate.)
Is the warped combustor pan causing any problems that you can see? Did they mention anything to look for, due to the warped pan?
This time of year, when the stove has burned pretty low before I reload, I'll do top-down starts..big splits in the bottom, a couple smaller splits, couple kindling and a firestarter in the top/front of the load. It's a very clean start..as the fire works its way down from the top, smoke from the wood that's catching below rises into the flame and is consumed. Having the fire in the top of the box also heats up the cat area of the stove more quickly so you can get light-off sooner. I find that I don't have to wait for the stove top to hit 250, as they mention in the manual. I use the flue meter more than stove top meter, when I'm ramping up a fresh load.
You need really dry wood, for earlier light-offs and easy top-down starts. Hopefully you have dry wood, since you've been burning stoves for a while.
Congrats, you scored a great little stove that is well-built. You will come to love it, I'm fairly certain. One thing I like is sitting at my desk, then looking over to see the cat glowing. :cool:
20191105_214453.jpg
BTW, what is the size and layout of the area you are heating with the stove?
 
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Hey Woody,
Thanks for the reply. That’s comforting to know that a bit of creosote in the firebox is not completely out of the norm for catalytic stoves.
When I first discovered the warping I called Woodstock and talked to them about it. they had me check for any other warping in the firebox and any cracks. Didn’t find any so we worked on getting a good seal with the bypass cover. They feel it’s good to go now but that the pan will need to be replaced sooner rather than later.
My wood is honestly not the best. Life has a way of getting in the way, new house, marriage, new baby, other house projects... you get the idea. My wood has been down for at least 2 years, split for over 1, but I use tarps to keep it dry so that never works great. A proper wood shed is in the plans for next summer.
I’m heating maybe 1800 square feet. Stove position in the house isn’t great but it’s in the living room which is 2 feet lower than the rest of the house so heat does flow out pretty well. Then an open stairwell in the center of the house sends heat upstairs pretty well. I know I can’t heat the whole house in a real cold snap but I sure can offset the oil bill.
 
You probably know already, but just cover the top with the tarp, that way the wind can blow through the sides and keep drying the wood. I have a couple spots near the door where I stage wood for the stove, where it's protected better from blowing rain and can dry out before I bring it in.
With damp wood, you might need to leave some flame going in the box after you close the bypass so that the cat gets going well. You just have to experiment, then go outside and see how clean the plume looks. You get a pretty good feel for it in short order, but there are quite a few variables that factor in.
"White smoke or no smoke from the chimney, rising temps after engaging the CAT, and visible glow at times." All of this indicates that you are already doing quite well.
1800 sq.ft. is quite a bit for a stove this size but if your insulation and air-sealing is pretty good you might put a major dent in your heating bill. If you run a little flame in the box, the sides will throw a bit more heat. The flame will burn some of the smoke so the cat may not burn quite as hot. If you try that, keep an eye on the stack to make sure the plume stays clean, and smoke isn't blowing past the cat. The load won't last as long and more heat will go up the flue, but this might be a better way to run when your wood isn't optimal dryness..try different approaches and see what happens. ==c
 
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Alrighty, thanks for the help! I think I will try running a bit hotter with more flame, see if that solves some of my creosote issues.

thanks again!
 
Another thing you can do for a little more heat at the end of the burn is to open the air up a little more, once the load is coaling. That will also bake any creo inside the box, as the coal bed glows more and radiates against the walls.
I generally run my cat-only burns with the air control at maybe .5-.75. But if I need more heat while waiting for the coals to burn down before reloading, I might open the air to 1.0-1.25. Of course, your air settings will differ depending on your draft. I have about 16' of insulated flex liner, rear-vented into a tee.
Like I said, I don't notice or worry about the creo too much, and I think once you have some drier wood, you won't be seeing as much, and it won't be wet. I'll get a couple pics when this load burns down.
Does your wood bubble moisture out the ends when you are ramping up a fresh load, or do you hear sizzling or hissing?
 
Most of my creo is around the door frame toward the back, the fastest-cooling area of the stove. You can see a little dried glaze in the other back corner. I think that is under the non-shiny stuff that is forward of that. I will have to check when the stove has less coals. Stage 3 creo in the box..I hope it doesn't catch fire. ;)
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Hello esparent, any insights into how long the Keystone will burn when on the lowest air setting?
 
any insights into how long the Keystone will burn when on the lowest air setting?
Mine will go 8-10 hrs. putting out decent heat, more than 200 degrees stove top, but there are coals in the ash for a full day. ;)
If I need more heat while I'm waiting to reload, I can get 300-350 stove if I open up the air a bit on the coals.
Depending on where you stir the ash down through the grate, you can get the stove to burn hotter there on the air that comes up through the grate, a handy feature.
4:41 AM..did you get up to reload? :oops:
 
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Hello esparent, any insights into how long the Keystone will burn when on the lowest air setting?
Hey DBoon,
I'm not sure what exactly constitutes "burn time". If I'm home on the weekend I typically load it at 6-7am, then when I load it at 12-1 there is a 2-3 inch layer of large hot coals. I've been burning a bit hotter - going for 400-500 stove-top temps with nice lazy flames in the box that come and go. During the week when I go to work I load it at like 630 and don't get home till 5pm and theres still enough coals to get the fire going again without too much trouble.

Since my initial post I've had another couple weeks of running the stove. The lower edges of the door and just inside the door are still shiny with some creosote. The glass is dusty but otherwise things seem to be going pretty well.
 
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