# Chimney Liner Crisis!!

I took geometry in Junior high and I'm wondering how you think making a round into a oval would change the volume? Am I missing something.

Look at the extreme case - imagine you continued ovalizing it until it was just a straight line. Then the volume would be zero. That indicates that moving the cross-sectional shape from a perfect circle to an oval decreases it's area (and therefore the volume of the liner). Here's another explanation:

http://mathcentral.uregina.ca/QQ/database/QQ.09.06/s/kathy2.html

Smoke and gases travel up in in a circular pattern, that is why a Round liner gives you the best draft, Oval is the next best, and with Square and Rectangle liners you loose a lot of that area in the corners.

Got it ! Is there a much of a factor when it comes to smooth wall or ribbed ?

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When using a Smooth Wall Liner, for Gas there is a 20% BTU capacity increase and with Oil a 15% BTU capacity increase in draft, I have not seen anything on what it does with wood burning appliances

Mark8
Golly gee... I am a frugal 20 something... but all this is really steering me towards just pulling the trigger on the ovalized rigid duraliner

When things seem overwhelming just take a deep breath walk away from the situation and collect your thoughts, just think of the education your getting for free, that's priceless

Look at the extreme case - imagine you continued ovalizing it until it was just a straight line. Then the volume would be zero. That indicates that moving the cross-sectional shape from a perfect circle to an oval decreases it's area (and therefore the volume of the liner). Here's another explanation:

http://mathcentral.uregina.ca/QQ/database/QQ.09.06/s/kathy2.html

Well that's the problem right there, I passed geometry but failed algebra

double-d
Got it ! Is there a much of a factor when it comes to smooth wall or ribbed ?
Yes but if you go with smoothwall dont get the 2 ply crap. Go with mid weight or heavy wall flex

can someone check out this laundry list of goodies and confirm that this will probably do the job and that the price is congruent with installing oval liners?

5- 6"x48" Oval Rigid Duraliner
1-6"x60" Oval Flex Duraliner
1-10"x22" Extend-a-cap kit
1-6"x14" Oval to round connector

grand total: \$1572 USD

or this...

If you want to insulate the flex sections you'll need wrap insulation for them.

When I did my oval duraliner install I had to send the oval flex down first and then attach the solid sections as it went down. I then had to get the oval flex down through the damper so I could attach the oval to round flex piece, then shimmy everything back up into place. Just consider how you are going to attach the oval to round flex piece if it doesn't fit down from above. You aren't going to send rigid flex pieces up through the bottom like you may be able to a ovalized flex liner.

I'll let others speak to the costs vs different options down there.

If you want to insulate the flex sections you'll need wrap insulation for them.

When I did my oval duraliner install I had to send the oval flex down first and then attach the solid sections as it went down. I then had to get the oval flex down through the damper so I could attach the oval to round flex piece, then shimmy everything back up into place. Just consider how you are going to attach the oval to round flex piece if it doesn't fit down from above. You aren't going to send rigid flex pieces up through the bottom like you may be able to a ovalized flex liner.

I'll let others speak to the costs vs different options down there.

how tight was your flue that you had to get through? I'm looking at the osburn flex kit that is much more reasonable , with an insulation wrap, but with a 6" OVAL and adding a blanket I want to ensure I can fit it down before blowing \$1000

how tight was your flue that you had to get through? I'm looking at the osburn flex kit that is much more reasonable , with an insulation wrap, but with a 6" OVAL and adding a blanket I want to ensure I can fit it down before blowing \$1000

If It was me I would get on a ladder and look down that flue to see what you have and do your own measuring, when I went inside my fireplace and measured just before the first piece of clay liner the size reduced down an inch. So before you purchase your pipe do your own measuring in various places just to make sure. Take a look at the mortar joints as well.

how tight was your flue that you had to get through? I'm looking at the osburn flex kit that is much more reasonable , with an insulation wrap, but with a 6" OVAL and adding a blanket I want to ensure I can fit it down before blowing \$1000

My flue that I lined with the duraliner was 6x13 interior dimensions. I'd do as Mark8 advised and have a look yourself and measure yourself. If you have chimney rods you can simply tape a chisel onto the end and have at the mortar snot if needed. I have a nice chisel now that attaches but I've taped one before and it worked. Either will be a good workout and an exercise in frustration. Also note that if doing this you are potentially knocking mortar right out of the joint and would be one more reason why the flue could never go back to being unlined. Like if converting back to a open masonry fireplace was desired as an option. Usually in these parts to fit a liner properly the damper area is going to need to be opened up some and negate the option of going back to a open fireplace anyways.

When I installed my insulated liner I had a heatilator style fireplace and I cut out one of the tubes and a portion of the damper/top of firebox.

I don't know if it's been mentioned/discussed yet but if you're going to all the work of doing it properly, then don't forget about a block off plate and insulation around the sides/back if it will fit and it's an exterior chimney.

wow I really appreciate all this info... my wife and I just moved into this house (our first) and all the diy projects have been fun but overwhelming to say the least... for instance I don't even own a ladder, a handy buddy with one is going to come over and help when it's installation time... I definitely do not have chimney rods or chisels for that matter. I really really want to make this happen as I have always wanted a wood burner and we are funneling money and heat out of our house with the electric heat pump (even though I guess dropping a grand and a half is kinda funneling money out too :/) but I'm almost at the point of thinking I need to give up because it seems I'm fighting an uphill battle on this.

Unless you are handy and have the tools an install like this could be tough and possibly worth hiring out to a pro. At the least you'll be armed with some knowledge to help you better determine if you're dealing with a pro or a hack disguised as a pro.

Installs can be from dead easy to super hard. And all stops in between.

Mark8
wow I really appreciate all this info... my wife and I just moved into this house (our first) and all the diy projects have been fun but overwhelming to say the least... for instance I don't even own a ladder, a handy buddy with one is going to come over and help when it's installation time... I definitely do not have chimney rods or chisels for that matter. I really really want to make this happen as I have always wanted a wood burner and we are funneling money and heat out of our house with the electric heat pump (even though I guess dropping a grand and a half is kinda funneling money out too :/) but I'm almost at the point of thinking I need to give up because it seems I'm fighting an uphill battle on this.

Here is some advice from someone three times your age, depending on the women your married to do not let a project like this interfere with your marriage or your relationship, if your not mechanically inclined and don't have the tools this could become very frustrating and if not installed correctly could burn your house down and kill you, whatever you do don't take shortcuts in the installation and follow the code. Bottom line, if you feel your over your head and this project is going to put a strain on your marriage, DON'T DO IT. Pay a professional, and keep the wife happy. I know this is not the Dr. Phil forum, just some friendly advice from someone that's been through a divorce.

Here is some advice from someone three times your age, depending on the women your married to do not let a project like this interfere with your marriage or your relationship, if your not mechanically inclined and don't have the tools this could become very frustrating and if not installed correctly could burn your house down and kill you, whatever you do don't take shortcuts in the installation and follow the code. Bottom line, if you feel your over your head and this project is going to put a strain on your marriage, DON'T DO IT. Pay a professional, and keep the wife happy. I know this is not the Dr. Phil forum, just some friendly advice from someone that's been through a divorce.

Haha wow man, thanks. I didn't really get the Dr. Phil vibe at all actually, that seems like sounds advice. I definitely am not the kind of person who likes to have a big investment 'half-assed' so no matter what route I go, I'm going to make sure it is done right, even if it means shelling out some extra coin for a pro to do it. To be honest, my wife is amazing and super understanding of most of my wild endeavors.

On this particular topic, she is concerned about the investment portion and whether it is actually 'worth it'. I tried to explain to her how we can get free wood, keep the house toasty (right now we have to bundle in blankets 24/7) and cut down on our electric bill, but yeah, you bring up another valid point. I think she would be far less understanding if I spent all that AND hurt myself, her or the house along the way.

Mark8
I'm not sure which brand of Smooth Wall Liner that is, but I know that some are NOT able to be Ovalized without having the inside ply "pucker up"

Which flu connector do you guys like better, I'm going to go with the 30 deg elbow because I like the fact when you clean your liner all of the creosote will fall down inside the insert, and the box type allows creosote to sit on top of your stove in the corners if it doesn't fall through the round flue. I'm also thinking it would draft better.

I went with the 30 stainless adapter. After researching I felt the same as you that it was the superior connection. Their 'box' connections that screw to the top seemed odd and dubiously effective for most all of the reasons you listed.

A heads up I had to crimp the male end of that adapter to fit into my stove collar. It didn't come crimped. A simple hand crimp worked fine.

Mark8
what about busting out the clay flue (professionally) and just buying a normal liner setup after, anybody wanna vouch for that?

I like the 30 deg angle idea, the liner a lot of times, after coming through the damper area is at about a 35 deg angle and this makes it easier to connect, than trying to make another bend down into the insert. When I say easier, most inserts are difficult to get in there to make that connection, because of the lack of room.

Mark8
I like the 30 deg angle idea, the liner a lot of times, after coming through the damper area is at about a 35 deg angle and this makes it easier to connect, than trying to make another bend down into the insert. When I say easier, most inserts are difficult to get in there to make that connection, because of the lack of room.

It would be nice if the flex would bend so you could just attach it straight to the stove avoiding any offsets but it appears that the flex is really not all that flexible, my installer kinked my flex just hooking it to the 30 deg box.

But your correct, there is a lack of room.

what about busting out the clay flue (professionally) and just buying a normal liner setup after, anybody wanna vouch for that?

Good question, who would you call for an estimate. Does this type of work fall under chimney sweep.

Any one know.

what about busting out the clay flue (professionally) and just buying a normal liner setup after, anybody wanna vouch for that?
We break out liners all the time but try to avoid it on fireplaces unless the tiles are already destroyed.