Is this the expected catalytic glow?

[mmcc]

Hi All - I've noticed that when my new-to-me Woodstock Soapstone Keystone is nice and hot, I can see that catalytic combustor glowing if I peer through the scoop. However, the glow always seems to be only on the right side (from the observer's point of view).

I attached a picture which attempts to show this, if you can ignore the reflection of the photographer. The glow on the left is gunk on the scoop burning off.

Is this the expected behavior? I would assume the whole thing should be a-glowin'.

 

[webby3650]

How old is the cat? Have you verified it's not partially clogged with ash? It won't glow all the time, but when it does I would expect a more uniform glow.

 

[mmcc]

How old is the cat? Have you verified it's not partially clogged with ash? It won't glow all the time, but when it does I would expect a more uniform glow.

How old is the cat?
The stove was made in 1996. I just bought it. The cat is of the steel variety, which apparently means it isn't the original one, which would have been ceramic. That's a long way of saying I dunno.

Have you verified it's not partially clogged with ash?
It wasn't clogged when I had the cat out prior to installing the stove. I've had maybe 10 fires since it was installed.

 

[fire_man]

My Palladian sometimes only glows on one side when I first engage the cat but after 5 minutes or so it evens out and the whole thing glows. I've noticed it seems related to which side of the load is chared the most.

Try flipping it around and see if the right side still glows, that would at least say the cat is ok.

 

[Woody Stover]

I've noticed that when my new-to-me Woodstock Soapstone Keystone is nice and hot, I can see that catalytic combustor glowing if I peer through the scoop. However, the glow always seems to be only on the right side

Do you always run that much flame in the box? I'm guessing yes, with that much ash on the expanded-metal mesh already. Where do you have the air set on that load? What happens when you cut the air to a cat-only burn, no flame?

My Palladian sometimes only glows on one side when I first engage the cat but after 5 minutes or so it evens out and the whole thing glows. I've noticed it seems related to which side of the load is chared the most. Try flipping it around and see if the right side still glows, that would at least say the cat is ok.

Same here, usually glowing all the way across. If the load is consistently burning
hot on one side, that side of the cat will tend to glow more. Load consistently burning hotter on one side could be due to an air leak, air wash needing adjustment, etc. Yeah, you could turn the cat the other way, but you'd have to replace the interam gasket around the cat since you would have to take the frame apart....I think...maybe it would work the other way, not sure. The frame isn't symmetrical.

 

[mmcc]

Do you always run that much flame in the box? I'm guessing yes, with that much ash on the expanded-metal mesh already. Where do you have the air set on that load? What happens when you cut the air to a cat-only burn, no flame?

Is that too much flame? The air is set somewhere between 0 and 1, probably closer to 1. At that level, I'm getting STT between 500 and 600 degrees and about 150 degrees lower in the flue, so I figured that was about right. I'll try running it lower to see what happens.

 

[Blazing]

I agree seems like a lot ash on that shield. It wouldn't take long to plug a cat with that much heading it's way. I'd try a vacuum or canned air and see if it gets any better before I pulled it.

 

[mmcc]

I agree seems like a lot ash on that shield. It wouldn't take long to plug a cat with that much heading it's way. I'd try a vacuum or canned air and see if it gets any better before I pulled it.

OK - I'll open 'er up and see how the cat is looking, and attempt to clean off the shield.

I've been burning 6 ecobricks at a go, stacking them in 3 layers. I haven't had any issues with overheating, but maybe that gets the fire too close to the scoop.

 

[webby3650]

OK - I'll open 'er up and see how the cat is looking, and attempt to clean off the shield.

I've been burning 6 ecobricks at a go, stacking them in 3 layers. I haven't had any issues with overheating, but maybe that gets the fire too close to the scoop.

Too close wouldn't really be an issue. Perhaps the eco bricks have excessive dust and ash?

 

[mmcc]

Too close wouldn't really be an issue. Perhaps the eco bricks have excessive dust and ash?

That's entirely possible. The bricks are made of compressed sawdust, and tend to kinda disintegrate when they burn. I don't end up with an abnormally large amount of ash left over, but they might make more light fluffy bits than standard firewood.

 

[mmcc]

That's entirely possible. The bricks are made of compressed sawdust, and tend to kinda disintegrate when they burn. I don't end up with an abnormally large amount of ash left over, but they might make more light fluffy bits than standard firewood.

I did a little Googling after writing that. If you believe their marketing literature, they produce 52% less particulate matter than cordwood:

http://www.ecobrick.net/sites/default/files/download_items/9x12_Ecobrick_Trifold.pdf

I have no idea how reliable that claim is, but they do have some sciencey looking charts.

 

[webby3650]

Maybe the bricks don't make enough smoke to get the cat glowing good?

 

[mmcc]

Maybe the bricks don't make enough smoke to get the cat glowing good?

Maybe. I'm also not arranging them as the manufacturer suggests - they go for a lot less airflow through the bricks. I should probably do what they suggest.

 

[Woody Stover]

Is that too much flame? The air is set somewhere between 0 and 1, probably closer to 1. At that level, I'm getting STT between 500 and 600 degrees and about 150 degrees lower in the flue, so I figured that was about right. I'll try running it lower to see what happens.

That's OK, you can run it with some flame in the box, and get a bit more heat off the sides of the stove. But the flame will eat some of the smoke, that's why I wondered what you are seeing when burning with no flame. 500-600 is a safe temp on the stove top...that's generally what I see with the meter placed right in front of the top flue plate, over the cat, the hottest area of the stove top. I've never burned the bricks so I don't know if the cat burns a little differently, compared to using cordwood. You'll have to see how fast ash builds up on the face of the steel cat when using the expanded metal/cast iron scoop. The stainless scoop has a fine-mesh screen so it will catch some of the ash and keep it off the face of the cat. Once in a while I let the stove go out and bush off the screen...you don't need to take it out to do this.

 

[mmcc]

That's OK, you can run it with some flame in the box, and get a bit more heat off the sides of the stove. But the flame will eat some of the smoke, that's why I wondered what you are seeing when burning with no flame. 500-600 is a safe temp on the stove top...that's generally what I see with the meter placed right in front of the top flue plate, over the cat, the hottest area of the stove top.

Well, I did a burn last night and put the air intake at 0 after the fire was well established and the stove was good and hot. I still got significant flame, so I'm guessing I have some leakage. The stove top - with the thermometer placed right in front of the top flue plate - didn't get above 550. I would interpret that to mean that the leakage isn't major, and I can safely use the stove till spring. I'll replace all the gaskets, and probably the cat and scoop, when it warms up.

 

[Woody Stover]

put the air intake at 0 after the fire was well established and the stove was good and hot. I still got significant flame, so I'm guessing I have some leakage....didn't get above 550. I would interpret that to mean that the leakage isn't major, and I can safely use the stove till spring. I'll replace all the gaskets, and probably the cat and scoop, when it warms up.

What is the height of your liner? I have 16', rear-vented, and once I cut the air under 1, there's no flame....well, once in a while I will get some floater flames with the air below 1.
If your stack is tall, you might be able to easily install a pipe damper like I did here, going in through the top flue exit after removing the plate. If you can reach back in there and hold the plate with one hand while you thread the damper rod through with your other hand, great.
https://www.hearth.com/talk/threads/new-to-me-woodstock-soapstone-keystone.160166/#post-2150947
But even with a tall stack, I would think you should be able to still get the flame burning fairly low with the air cut, but it sounds like the flame is still pretty lively, so I'm guessing you have extra air getting into the box.
To determine if air is being pulled in somewhere, first check your gaskets with a dollar bill all the way around the perimeter of each gasket. It should offer some resistance when pulling the bill out. Also observe how the stove is burning. Are the coals consistently glowing brighter, or are the flames bigger on one side of the load? (There will always be some glowing in the coal bed, as there is a vent hole in the back of the ash pan housing.) When conditions in the box are right, like when you have a lot of wood gassing on a fresh load, then you cut the air all the way, you may be able to see flame erupting where air is entering the box. It may take a while watching the stove before conditions are right and you can see it. I saw the flame erupting along the left front vertical seam in my stove, plus the fire burned brighter on that side. The leak gradually got bad enough to where it ran like your stove is now....always had flame in the box and STT would go to 550 every time. I got some of the furnace cement that Woodstock makes and re-sealed that seam. Great cement, very stringy and tacky.
http://store.woodstove.com/product.php?productid=16577&cat=279&page=1

 

[mmcc]

What is the height of your liner?

It is something like 23'+ - full length of my chimney, which clears the peak of my 2 story colonial by a bit.

I actually have a flue damper just above my tee - I've never messed with it. Maybe I'll give it a go the next time I have a fire and get everything up to temp.

 

[Woody Stover]

23' will pull pretty strong. The pipe damper may temper that a bit. I'd still investigate for possible air leaks. Another thing you can do is light an incense stick when the stove is running and draft is strong, then go along the seams and see if the smoke is drawn in anywhere. Oh, check the glass gasket too when the stove is cold. Glass should be tight, not loose and moving around.

 

[mmcc]

23' will pull pretty strong. The pipe damper may temper that a bit. I'd still investigate for possible air leaks. Another thing you can do is light an incense stick when the stove is running and draft is strong, then go along the seams and see if the smoke is drawn in anywhere. Oh, check the glass gasket too when the stove is cold. Glass should be tight, not loose and moving around.

I haven't looked for leaks yet, but I have found that if I close the air intake to 0 and close the flue damper, after the initial heavy off-gassing I get low flame and glow from the entire cat. So, good enough for the time being.

It looks like it going to be cold next week, so I'll get to mess around with it some more.

 

[ddddddden]

. . .I get low flame and glow from the entire cat. So, good enough for the time being.

Yep, that's how Woodstock cat stoves burn(not sure about their newer steel hybrid stoves.) If you are getting enough heat, that's as good as it gets. You can turn up the air a bit for more flames and a faster burn, if you need more heat sooner, but a faster burn is less efficient in these stoves. Lazy flames and glowing cat is my usual burn target. Don't get too hung up on the cat glow though. Sometimes only parts of it glow. Sometimes there is no glow, but you can tell it's working because there is no smoke coming out of the chimney.

I usually set the air control at a lil' less than 1. If you find yourself often running at 0 with the pipe damper closed, I think Woody is right; you might have some leaks. . .or the slider in the air intake could be off-track (look in back with a flashlight.)

Every install is a bit different, but my chimney liner is ~ 23' vertical, and I've run the stove with air at 0 one time in 5 years, when it was particularly windy out. . .I think my door gasket was leaking a bit too.