Bright Orange versus Cherry Red??? Color of Inside Cast Iron Cover Plate to Catalytic Converter

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Cath

Feeling the Heat
Hearth Supporter
Jul 31, 2007
295
So, DH is testing some BioBricks and gets the fire going pretty good in the VC Winter Warm small. He closed the damper and we're enjoying the cozy heat. Half an hour into it I am chilled by these words "I don't like that cherry red".

Next thing you know I'm on the floor looking up towards the back of the inside of what DH describes as a cast iron cover plate to the Catalytic Converter. I would describe it as a rectangular opening.

To me it didn't look cherry red but rather a very deep orange about as deep as the deepest orange in the fire itself (which DH agreed with when I described it that way). He opened the damper up and the orange lessened noticeably within 5 or 10 minutes.

Am I being too literal? Is this the cherry red color I've read warnings about on this site? And if so, is it abnormal under these circumstances? And what do you do to prevent it?

I guess I should also ask if this isn't actually the cherry red you hear about, how close was it? And what does it say about how the fire should be tended?

BTW, he seems pleased with the BioBricks so far.
~Cath
 
Cath, if I'm not mistaken, the Winterwarm is a catalytic stove is that correct? If so, what you are describing sounds like the catalytic converter glowing which is a good thing. It shows its working strongly burning the excess gases that otherwise would be going up the flue. When you opened up the air you raised the temperature of the firebox and decreased the amount of unburned gases which lowered the amount for the cat to burn and reduced the glow. At low burn rates, its typical for your combustor to glow like that though assuming you warmed your stove up enough before you engaged it, it would be working even if it weren't glowing. If it was your combustor, no worries, that's fine.
 
Cath normal operation. congrats you have Cat combustor ignition. there is a lot of heat required to burn smoke particles and it is common to see a cat glow. Now if the outside of that stove glowed that would be a concern It is also possible to see the hood cover to the cat combustor to glow a bit again that is normal. Inside that Cat combustor compartment it can get to 1500 degrees again normal. You might find a combination of the bio bricks mixed with cord wood to work best. It could be the bio bricks being so dry could use normal cord wood mixed in.

You will have to experiment to find the settings and wood load combinations that work best. Maybe something like this, 3 bio bricks to establish the fire, then once going some cord wood on top
 
elkimmeg said:
Cath normal operation. congrats you have Cat combustor ignition. there is a lot of heat required to burn smoke particles and it is common to see a cat glow. Now if the outside of that stove glowed that would be a concern It is also possible to see the hood cover to the cat combustor to glow a bit again that is normal. Inside that Cat combustor compartment it can get to 1500 degrees again normal. You might find a combination of the bio bricks mixed with cord wood to work best. It could be the bio bricks being so dry could use normal cord wood mixed in.

You will have to experiment to find the settings and wood load combinations that work best. Maybe something like this, 3 bio bricks to establish the fire, then once going some cord wood on top

Elk,
Yes Houston, we have Cat ignition.

Now I know the correct term, it was the inside of the hood cover (primarily the back) that was glowing.

He started with the cord wood and put the bio bricks on top but based on your input I'll suggest he try it the other way next time.

One more thing, he just told me he's surprised that there very little smoke coming out of the chimney. Guess that Cat is working!

Have a great weekend!!!
~Cath
 
Cath, I'll wait for the official word from biopellet, but you want to be very careful using bio-bricks in combo with wood. They have a lot more energy than the average log and are really designed to be burnt alone, en masse, for the best operation. Putting them on top of the cord wood can cause them all to ignite at once which will release a lot of btus suddenly. That can be stressful to the stove and more than a little exciting. I'm guessing that this is why you saw the orange glow.
 
To be clear, the cat itself can glow, but if the cast iron cover is glowing regularly, you will soon have to replace it. Not really a danger, and some cat covers (or deflectors) are actually made to replace easily. Cast iron is not designed to glow. That is a job for other metals such as stainless, etc.
 
BeGreen said:
Cath, I'll wait for the official word from biopellet, but you want to be very careful using bio-bricks in combo with wood. They have a lot more energy than the average log and are really designed to be burnt alone, en masse, for the best operation. Putting them on top of the cord wood can cause them all to ignite at once which will release a lot of btus suddenly. That can be stressful to the stove and more than a little exciting. I'm guessing that this is why you saw the orange glow.

BeGreen,
To be clear, does this mean you can't mix in cordwood at all? Or does it simply mean that the cordwood should go on top so the intense heat of the BioBricks doesn't reach the Cat?
~Cath

Webmaster said:
To be clear, the cat itself can glow, but if the cast iron cover is glowing regularly, you will soon have to replace it. Not really a danger, and some cat covers (or deflectors) are actually made to replace easily. Cast iron is not designed to glow. That is a job for other metals such as stainless, etc.

Craig,
Good to know, we'll continue to keep a close eye on what's going on with the cast iron cover.
~Cath
 
I'd prefer not to speak for the manufacturer, but if it were me I would only put 2-3 on an existing cordwood fire. Burned unmixed, their benefit is a clean and slow burn. That seems to be somewhat lost by mixing them with wood.
 
Cath said:
So, DH is testing some BioBricks and gets the fire going pretty good in the VC Winter Warm small. He closed the damper and we're enjoying the cozy heat. Half an hour into it I am chilled by these words "I don't like that cherry red".

Next thing you know I'm on the floor looking up towards the back of the inside of what DH describes as a cast iron cover plate to the Catalytic Converter. I would describe it as a rectangular opening.

To me it didn't look cherry red but rather a very deep orange about as deep as the deepest orange in the fire itself (which DH agreed with when I described it that way). He opened the damper up and the orange lessened noticeably within 5 or 10 minutes.

Am I being too literal? Is this the cherry red color I've read warnings about on this site? And if so, is it abnormal under these circumstances? And what do you do to prevent it?

I guess I should also ask if this isn't actually the cherry red you hear about, how close was it? And what does it say about how the fire should be tended?

BTW, he seems pleased with the BioBricks so far.
~Cath

The physical explaination of this can be found in Wien's Law which observes that the peak color emmited by an object is inversly proportional to the temperature of an object.

http://en.wikipedia.org/wiki/Wien's_displacement_law

To get celsius subtract 273 from Kelvin. To get Fahrenheit TF = (TC × 9/5) + 32. A dull red glow is around 1200F
 
BeGreen said:
Cath, I'll wait for the official word from biopellet, but you want to be very careful using bio-bricks in combo with wood. They have a lot more energy than the average log and are really designed to be burnt alone, en masse, for the best operation. Putting them on top of the cord wood can cause them all to ignite at once which will release a lot of btus suddenly. That can be stressful to the stove and more than a little exciting. I'm guessing that this is why you saw the orange glow.

If you put BioBricks(tm) on top of cordwood you get maximum surface area which makes for maximum woodgas generation. In a wood/oil furnace of a friend of mine this lead to puffing as the gases ignited in a great release of energy....
 
BioPellet said:
Cath said:
So, DH is testing some BioBricks and gets the fire going pretty good in the VC Winter Warm small. He closed the damper and we're enjoying the cozy heat. Half an hour into it I am chilled by these words "I don't like that cherry red".

Next thing you know I'm on the floor looking up towards the back of the inside of what DH describes as a cast iron cover plate to the Catalytic Converter. I would describe it as a rectangular opening.

To me it didn't look cherry red but rather a very deep orange about as deep as the deepest orange in the fire itself (which DH agreed with when I described it that way). He opened the damper up and the orange lessened noticeably within 5 or 10 minutes.

Am I being too literal? Is this the cherry red color I've read warnings about on this site? And if so, is it abnormal under these circumstances? And what do you do to prevent it?

I guess I should also ask if this isn't actually the cherry red you hear about, how close was it? And what does it say about how the fire should be tended?

BTW, he seems pleased with the BioBricks so far.
~Cath

The physical explaination of this can be found in Wien's Law which observes that the peak color emmited by an object is inversly proportional to the temperature of an object.

http://en.wikipedia.org/wiki/Wien's_displacement_law

To get celsius subtract 273 from Kelvin. To get Fahrenheit TF = (TC × 9/5) + 32. A dull red glow is around 1200F

oh yeah, average steel has a melting point of around 2500 F ....
 
Plain Grey (class 30) Cast iron is not designed for service much above 1000 degrees. Hotter temps than that will cause it to warp, flake, crack and turn orange. Sometimes it will also "grow" as it peels apart almost like something that is rusty.

VC usually designs these hoods to be easily replaceable - check the part number and hopefully it is not part of a large assembly.

Even the best cast iron, with other materials added for higher heat service, cannot survive for too long if it glows regularly. That might mean 2 years or 3 years - depending on when the part warps enough to get in the way of things or stop working as it should.

We had a lot of experience with this kind of stuff when coal stoves were popular in the early 80's.

The alloy is very important, as is the shape. But it seems unlikely that VC would pour too many various alloys since they are highly automated. They may even outsource some parts.....if they have high nickel content, etc.

Also, temperature rating of a metal obviously depends on what it is being used for. A stove is a very crude use, so as long as the casting exists and does not crack or warp....it is usually ok.
 
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