Insert question

[itsanaddiction]

These may sound like dumb questions, but I'm a newbie here so bear with me. I see more experience on this web site than I could accumulate in a lifetime, I'm asking for advice.

I've put an insert into my fireplace, and run a 6" ss liner up and out the old fireplace chimney. Using a piece of tin, I made a square cap for top of the chimney with a 6" hole in it, where the liner exits. OK, I'm looking at others pictures on this site and reading up, I see one picture where there is insulation stuffed in around the ss liner above the stove where the liner enters the chimney. I didn't do this, should I?

Also, I had an incident recently, this is my other question; I had the flue wide open for too long trying to get the thing lit. (First mistake, ashes where going up and out and I think it just got too hot). Then I noticed flames coming from the top of the chimney. I went up there with a fire extinguisher and put it out. Here's what happened... I had used hi temp sealant were the ss liner met with the tin cap I made to cap the chimney. It was the same stuff used to seal the front of the fireplace doors, so I didn't think twice about it getting too hot. The sealant was what caught fire, nothing else. I cleaned the whole thing, and have used it several times since with no issues.

The insert is a Kent Logfire I bought used, the prev owner had the original reciept from when he bought it in 1990. Any thoughts?

 

[ROBERT F]

So the flames were not from the flue? but from around the outside of it? where the top plate meets the flue pipe? And insulating as much of the liner/chimney cavity can be helpfull, but its got to be the right kind of insulation. The times you see it at the "bottom" is because its sealing the chimney like a lower block off plate.

 

[itsanaddiction]

Yes, the only thing that burned or was on fire was the hi temp silicone around the flue pipe where it came through the top plate. So, no more silicone to seal that part. My other question was should I use insulation around the liner just above my insert? It warms up nicely in the room, how much heat am I losing up the chimney?

 

[drdoct]

The first thing I would suggest is going to a chimney website like magnaflex or chimney liner depot and buy a cap that fits what you've got. It will seal off your chimney top much better and also protect it from rain and support it all when you get it cleaned. It uses a band clamp to hold onto the liner. If you seal that up good then you don't have to have a blockoff plate. I would suggest one, but it isn't mandatory like sealing the top is. I'd say you're pretty lucky you didn't burn your house down or something like that with a good little fire up on top of your chimney. Some people use a simple kitchen timer to just remind them when their doors are open. My house is so little that I can start to smell it long before it gets too bad.

 

[jtp10181]

Your liner should be fully insulated from bottom to top with an approved insulation wrap. Unless your current masonry chimney meets all NFPA 211 guidelines and passed a Level II inspection from a certified chimney sweep. Without the insulation wrap the SS liner is only acting to reduce your flue size and is not really adding any sort of safety factor to the system in the event of a chimney fire.

Also as others suggested, get a proper top plate and cap for your liner.

 

[oconnor]

Your liner should be fully insulated from bottom to top with an approved insulation wrap. Unless your current masonry chimney meets all NFPA 211 guidelines and passed a Level II inspection from a certified chimney sweep. Without the insulation wrap the SS liner is only acting to reduce your flue size and is not really adding any sort of safety factor to the system in the event of a chimney fire.

Also as others suggested, get a proper top plate and cap for your liner.

What he says. Give the liner best practices link in my signature block a read.

 

[BrotherBart]

I wanna know how in the hell you get the liner hot enough up at the top plate to set silicone on fire? Back when my old pre-EPA stove ran away, twice, with stove top temps of 1200+ degrees that plain old hardware store silicone up there looked good as new. The temp in the flue had to be monstrous when it happened. That stuff doesn't cook off until around eight hundred degrees.

There is more to this story...

 

[webby3650]

It sounds to me like your flue didn't get cleaned well before you put an un-insulated SS liner down it, is this correct? I believe you had a flue fire outside of the SS liner, that is how it got hot enough to burn the silicone.