Need help with flex liner install on Buck 91 insert trying to replace a 'slammer' install.

[WoodpileOCD]

OK, I've decided that I really need to put a liner in my external 20' masonry chimney. I had a old, old Black Bart insert until the middle of last season and found a great deal on a used Buck 91 insert. I did a 'slammer' install because that was the way my old one was run for 15 years and I didn't know any better. Now I do. I have some issued that I am going to need help with and know that this is the place to be. Thanks in advance for the great advice I know I'm going to get.

Here's the deal. I have a 12"x12" clay liner and need an 8" SS flexliner. It is a straight shot right down to the damper plate opening so no problem getting it down there. The opening for the damper (damper removed) is 5.5" as best I can measure up in there. If my drawings can be read alright in the picture you can see the dimensions I'm dealing with and the limited space I have to work with as well.

My first question is How flexible is a flex liner? Am I going to be able to squash it down to go through that opening and then make the turn and round it back out to go into the vertical appliance adapter that attaches to the end of the liner. As you can see I have about 13" to work with from the top of the stove to the bottom of the damper opening. Having never touched one of these guys, much less tried to bend one, my gut tells me that I'm going to have to do some cutting and brick removal to get it in there.

Question 2. What are the implications of removing the middle top brick just below the opening (see picture) to give me some room to bend the liner. I'm going to end up with an 'S' curve if I'm picturing it right. As you can see in my drawing, the opening to the stove is only about 4 inches from the back wall with the stove fully shoved into the fireplace. I can pull it out some if I have to but would have to add a hearth extension (which I'm going to do anyway as it is too short now).

This is going to be way more challenging than I thought but such is life these days. Been WAY too long since one of my projects went easier than I expected I'm prepared to cut part of the damper frame out in the back but was unsure about breaking out one of the bricks.

Any help or advice would be greatly appreciated. Also, what about reducing to a 6" liner. The stove shop here said that they do it all the time but I'm quite certain the efficiency of the stove would suffer (but how much?)

 

[Todd]

Can you cut out that old fireplace damper plate? Some are made out of cast iron and you can break them with a hammer.

 

[FireAnt]

This is just my opinion... I would cut the little plate rest off, and then cut along the outside of that grayish ash ring you have. I cut the plate rest off mine and made a little rectangular notch on the opposite side to get my 6" down. Just used a grinder.

 

[Loco Gringo]

I did it to install my Model 21 and Im sure you can too. Like Todd said, cut as much as you can. I did mine and I used an angle grinder. Man did that save my ass during my install which took me maybe 20 minutes start to finish by myself. The liner is flexible, but its no dryer vent either. I had to dog leg mine but it was no biggie, and you can oval it in order to make it pass, then pop it back round for your connection. I had to do that too even with a 6 incher so Im sure you will have to with an 8 incher. I wouldnt remove any brick as it may take from the integrity of the chimney itself, but thats just me and Im the paranoid type.

 

[coltfever]

woodpile I put a an 8 inch flex liner in mine this past summer. My fireplace is like what you have except my chimney tile is 13x18 inch and 23 foot tall. I cut my damper out with a 4 inch grinder and also cut out a couple of firebrick. I'm glad I removerd the brick. The flex liner has very little flex to it.( Flex-King Pro ) and with you having an 8 inch liner like mine you will need all the extra room you can get. This winter I will be using my Buck 26000 series and next year I hope to get a Buck 74 or an insert like you have . My fireplace opening is like yours 33 wide , 27 tall and I was able to cut my damper plate in half and use it for my block off plate . I like the looks of the Buck 91.

 

[WoodpileOCD]

I know I'm going to have to cut out at least part of my damper box. It looks like the lower portion is about a 1-2" strip which I should be able to get out fairly easily with a grinder but the top forward part looks to be a solid plate about 5-6" wide. From what I can feel up in there, it appears that even if I removed the whole thing it would only gain me a couple of inches as it sits on/against brick. It will probably be enough to ovalize the liner and get it through but I'm worrying about the sharp dogleg bend I'll have to make in a short space. I think I'm going to have to dogleg it and round it back into shape in about 12 inches.

Coltfever, thanks for the pictures. That's what I was thinking but it really helps to see it. It looks like your liner is coming into the insert at a 45 degree angle or thereabouts. Is that the case or just the perspective of the picture. That would make it a lot easier but the adapters I've seen that come with the kits come out of the stove at 90 deg which makes the dogleg more severe. The pictures are great. Thanks again.

 

[coltfever]

I guess its about 45 degree angle. If I were doing it again as you can see in the above picture I would have taken out 2 more chimney firebrick. I made sure I had at least a 12 inch opening in the damper area for the liner to drop down and thought that was more than enough but as you can see its still not much room for movement. Its kinda hard to tell how much movement you need in the flex liner until you get into place. I thought to myself, if I had only 2 more inch. But it all work out. Be sure to use a 4 inch grinder and saftey glasses and if you need to remove any brick. They make a grinder wheel for that also.
Good luck

 

[WoodpileOCD]

Finally pulled the trigger on a SS liner for my chimney. Ordered a 25' kit from Rockford Chimney with a 45 degree offset appliance adapter and the deluxe terra cotta cap (thanks Brother Bart for the encouragement on that part). I've decided to go with a block off plate and Perlite rather than an insulated sleeve, mainly because it will save me over $200 on the insulation. I had to spend another $90 because my chimney measured right at 20' to the top of my stove and the guy at Rockford said it takes about a foot to make the S turn at the damper. I'll take pictures of the install (just to make sure it actually happened) and keep this thread updated. Really looking forward to getting it in now so all my heat quits getting sucked out of my house and up the chimney.

Thanks for all the wisdom support and advice. I'm sure I'll need more before this is done.

 

[BrotherBart]

Glad it is moving along. How about you open a new thread to chronicle your install so folks don't have to wade down to the new stuff.

 

[WoodpileOCD]

Will Do