New Chimney Melting My Vinyl Siding

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Perhaps there was an air leak SOMEWHERE, chimney or stove, which might have caused the overfire.
 
Yes I am aware of that and turn the air down on the stove to compensate for that. I have 3 thermometers. 2 on each top corner of the stove and one on the stove pipe. Also on this stove there is a thermometer in the top plate of the stove right above the catalytic combustor. Even though the stove could be running between 300 and 400 degrees the catalytic thermometer usually runs between 750 and 1000 degrees. I don't ever load more than 6 bricks at any one time. View attachment 176100
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Yes I am aware of that and turn the air down on the stove to compensate for that. I have 3 thermometers. 2 on each top corner of the stove and one on the stove pipe. Also on this stove there is a thermometer in the top plate of the stove right above the catalytic combustor. Even though the stove could be running between 300 and 400 degrees the catalytic thermometer usually runs between 750 and 1000 degrees. I don't ever load more than 6 bricks at any one time. View attachment 176100
View attachment 176101
Perhaps there was an air leak SOMEWHERE, chimney or stove, which might have caused the overfire.
The stove has had new gaskets and cement over the summer and is air tight. All the stove pipe and chimney are brand new. I checked the bottom cap for the chimney outside and it was secure. When I replaced the chimney I also replaced everything from the stove up.
 
Here is a pic of the inside of the chimney after I cleaned it out. There was hardly any build up inside. the brush went up and down almost as if it was a new chimney. When I pulled it out nothing went on the ground.20160303_153451.jpg Everything looks to be intact.
 
Sorry for your problem. I burn normally firewood that is between 16 and 22 percent moisture.
I had an oak floor installed, 3 1/2 inch wide t&g oak. That wood is 8 percent. I had a bunch of scraps. I burned some of that stuff, damn did it burn hot.
I had that oak in 12 inch pieces, I couldn't put but 4 or 5 in there, any more and the heat would climb out of control.
So it is possible that your superdry blocks are just bad news to begin with.
 
The stove itself has been run hot a few times, granted it is old and you might not have done it since the new chimney but the white on the upper part is from overheating, I cant but help wondering if you are leaving the damper open to long burning those bricks and overheating, they will run off on you in a heartbeat if you leave them burning with the air wide open.
 
From the looks of the chimney it is not being run to hot or the cat is not working properly. I cant tell you why the siding is melting or that pipe sounds different but i would have a pro check it out. And yes you can have a fire with blocks in that stove.
 
Sorry for your problem. I burn normally firewood that is between 16 and 22 percent moisture.
I had an oak floor installed, 3 1/2 inch wide t&g oak. That wood is 8 percent. I had a bunch of scraps. I burned some of that stuff, damn did it burn hot.
I had that oak in 12 inch pieces, I couldn't put but 4 or 5 in there, any more and the heat would climb out of control.
So it is possible that your superdry blocks are just bad news to begin with.
I am having no problem keeping the stove at between 300 and 450. I just keep the air open 1/4 to 1/2 turn. I usually turn them 1 to 2 turns when burning regular seasoned firewood. I did have one time where the creosote in the stove pipe just above the stove got going pretty hot but I was there when it happened and shut the air off. It cooled down in less than 1 hour.
 
As someone already mentioned I thought the chimney would be able to stand up to not only use, but abuse and still protect. Curious to see what you find when you pull it down.
 
I did have one time where the creosote in the stove pipe just above the stove got going pretty hot but I was there when it happened and shut the air off. It cooled down in less than 1 hour.
How hot is pretty hot? Also an hour to come back down is pretty long.
 
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As someone already mentioned I thought the chimney would be able to stand up to not only use, but abuse and still protect.
Yes it will stand up to use but they should be thoroughly checked after a chimney fire. They will stand up to some abuse but they will fail eventually. I don't think the chimney has failed in this case but something is not working right and I cant tell from the picks or info what that is. Someone with experience really needs to get their hands and eyes on it to see.
 
The stove itself has been run hot a few times, granted it is old and you might not have done it since the new chimney but the white on the upper part is from overheating, I cant but help wondering if you are leaving the damper open to long burning those bricks and overheating, they will run off on you in a heartbeat if you leave them burning with the air wide open.
I painted the stove once about 10 years ago it has been light colored in that area for last 7 years at least. I have never left the damper open for an extended period. I usually run it open until it is hot enough to fire up the cat. The manual says that's 400 to 500 degrees. I never wait that long. Around 300 degrees will usually get the cat going with well seasoned wood and even less with the bricks because of the low moisture content.
 
It might not be heat from the flue doing this. I had a similar issue and it was the sunlight reflecting off my neighbors Windows. Google it...very common and overlooked problem with vinyl siding. You could be getting a double dose of heat from the chimney reflection given that it's a reflective surface.
 
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Have you checked the moisture in this wood? Thought you were burning bricks?
I am burning bricks (envi8) this year. I have burned them in past years some but this year my firewood guy retired so I have been burning them only. I went through 3 tons this year. I haven't checked it but it's supposed to be near zero. Every time I cleaned the chimney this year it was almost a waist of time since there was no build up at all.
 
It might not be heat from the flue doing this. I had a similar issue and it was the sunlight reflecting off my neighbors Windows. Google it...very common and overlooked problem with vinyl siding. You could be getting a double dose of heat from the chimney reflection given that it's a reflective surface.
I only get a short amount of sun light in the morning on that side of the house plus the siding was put up the third week of November and the neighbors house is not close enough to have any effect on my house. Also the only place the siding is warped is directly behind the discolored section of chimney pipe.
 
I am probably going to suck it up and use the electric heat for the rest of the year. I used a lift to put it up and the ground is probably too soft to get the equipment back there and I'm not going to try to do it with ladders5369.jpeg
 
You could be getting a double dose of heat from the chimney reflection given that it's a reflective surface.
Was going to ask if it was getting full sun exposure since I was thinking the same thing. Can't explain the discoloration and hollow sounding pipe section though.
 
Well, at the risk of stating the obvious, something got those lower sections too hot. It seems very unlikely a chimney fire in the new chimney sections from what you've said, but something got the lower sections very hot and reaching 160 F two inches away from the chimney to warp the siding doesn't seem too hard to do.

It just seems to go back to the possibility of a past overfire or stovepipe fire from a previous creosote buildup. I know that using straight bio brick products is somewhat controversial, especially in a cat stove, but it's hard to ignore the possibility of it being a contributing factor although you seem to be on top of that.

However, the fact that thumping on the sections yields a hollower sound in the lower section (?) is very interesting too. It would be very telling if you can determine if it was originally defective, or damaged from an overfire/stovepipe fire, or just a normal response for some reason.

I think you're right to stop burning until you can get everything evaluated properly. But in any case, you'll want to replace the siding in that location with Hardy Board or similar even when everything is sorted out. Good luck.
 
Well, at the risk of stating the obvious, something got those lower sections too hot. It seems very unlikely a chimney fire in the new chimney sections from what you've said, but something got the lower sections very hot and reaching 160 F two inches away from the chimney to warp the siding doesn't seem too hard to do.

It just seems to go back to the possibility of a past overfire or stovepipe fire from a previous creosote buildup. I know that using straight bio brick products is somewhat controversial, especially in a cat stove, but it's hard to ignore the possibility of it being a contributing factor although you seem to be on top of that.

However, the fact that thumping on the sections yields a hollower sound in the lower section (?) is very interesting too. It would be very telling if you can determine if it was originally defective, or damaged from an overfire/stovepipe fire, or just a normal response for some reason.

I think you're right to stop burning until you can get everything evaluated properly. But in any case, you'll want to replace the siding in that location with Hardy Board or similar even when everything is sorted out. Good luck.
The hollow sound has me stumped as well I sent the pictures to Selkirk and they are trying to figure it out. Usually when you have a chimney fire it burns its way up not just one section. Also there is no sign of anything wrong when you look up the chimney. Also if you look at my stove picture you will notice the inside black stove pipe is not discolored at all. If there was a fire in there I think it would turn the black to grey but it still looks new
 
Sounds like you're doing all the right things to figure it out. It's an unusual enough problem to be interesting, so please let us know what happens through this thread.
 
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The chimney is a class A solid pack and has a 2" clearance requirement to combustibles. I have 2 3/4" with my set up. I also used the outside wall brackets and hardware that Supervent sells for this installation.

You are confusing combustion temperatures with melting temperatures. Melting temperatures are less than combustion temperatures. A candle mostly melts and drips all over the place from the heat of a flame, but does not combust (well a little on the wick does get hot enough to combust some wax to keep the candle lit). Your vinyl siding is doing something similar: melting due to the heat from the chimney, but not cumbusting. And doing it at the base because that is where the exhaust is the hottest.

I suggest to install a heat shield between the chimney and the siding. A flat sheet of galvanized steel with at least an inch of air space on each side should do the trick.
 
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I am looking into making a heat shield up. It's amazing with so many houses having vinyl siding and no one is selling anything for this. Also all the mounting kits and brackets sold by chimney companies seem to have the same 2" to 2.5" clearances.
 
A heat shield will be treating the symptom, not the cause. The chimney pipe has overheated. The question is why. The lack of evidence in the stove pipe is not conclusive. You are doing the right thing by bringing in Selkirk. It could be there is a defective pipe there, but be open to the possibility that you may have had one or more runaway fires there when out or sleeping.
 
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