Damper installation in liner?

[John B]

Hi,

I've done some searching but haven't seen this specific question answered. I have a Kuma Sequoia insert in a brick fireplace which I am in my first season of burning. I have an 8" SS insulated liner which is a straight shot through a 27' external masonry chimney.

The SS liner has an appliance connector on the end and goes right into the stove. The SS liner bends around the smoke shelf and then curves back to the stove, which is deeply recessed into the fireplace. It all lines up well but was difficult to install.

This setup has some serious draft, more than the stove can take even with the primary all the way down. I built my own OAK and severely limited the primary air which has helped a lot, but I really think to get the most out of the setup I need a damper.

I figured out how to build a linkage system to put the damper control outside the surround, but I need to figured out the actual damper placement. Would it be ok to install the damper in the liner itself? Or even in the appliance connector?

The other idea I had was to get an SS 15 degree elbow and install the damper in that. The elbow would fit my install and actually reduce some of the bending of the flex liner so that might make for a nicer install overall.

Thoughts? Suggestions? Thank you!

 

[jetsam]

@bholler @webby3650 <- Both of these guys have done that.

 

[chazcarr]

I'd like to see that as well.

 

[bholler]

Hi,

I've done some searching but haven't seen this specific question answered. I have a Kuma Sequoia insert in a brick fireplace which I am in my first season of burning. I have an 8" SS insulated liner which is a straight shot through a 27' external masonry chimney.

The SS liner has an appliance connector on the end and goes right into the stove. The SS liner bends around the smoke shelf and then curves back to the stove, which is deeply recessed into the fireplace. It all lines up well but was difficult to install.

This setup has some serious draft, more than the stove can take even with the primary all the way down. I built my own OAK and severely limited the primary air which has helped a lot, but I really think to get the most out of the setup I need a damper.

I figured out how to build a linkage system to put the damper control outside the surround, but I need to figured out the actual damper placement. Would it be ok to install the damper in the liner itself? Or even in the appliance connector?

The other idea I had was to get an SS 15 degree elbow and install the damper in that. The elbow would fit my install and actually reduce some of the bending of the flex liner so that might make for a nicer install overall.

Thoughts? Suggestions? Thank you!

No you can't put a damper in a flex liner.

 

[spudman99]

Is that due to the physical limitations of the install or rather the lack of need/use on an insert application?

For instance, couldn't you install say a 6" piece of single wall with a key damper mated to the flex liner on either side with some insulation on the outside (so long as there is room through the existing fireplace damper) and then use an extension rod through the front of the fireplace?

I realize that is a somewhat intricate installation and would cause issues trying to clean the flue from one direction but I imagine it physically could be done.

Follow up question - how does one control excessive draft on an insert with a flexible SS liner?

 

[bholler]

Is that due to the physical limitations of the install or rather the lack of need/use on an insert application?

For instance, couldn't you install say a 6" piece of single wall with a key damper mated to the flex liner on either side with some insulation on the outside (so long as there is room through the existing fireplace damper) and then use an extension rod through the front of the fireplace?

I realize that is a somewhat intricate installation and would cause issues trying to clean the flue from one direction but I imagine it physically could be done.

Follow up question - how does one control excessive draft on an insert with a flexible SS liner?

Yes you can put a damper in a rigid peice of pipe but not a flex liner. Light wall is to thin and the hole would quickly enlarge. And drilling a 1/4" hole in heavy wall would compromise the structure of the liner

 

[velvetfoot]

On my stove, secondary air has the same source as primary.
Controlling intake air made a big improvement.
How far down do you close the oak?
I'm amazed at how little of an opening is needed.

 

[webby3650]

Yes you can put a damper in a rigid peice of pipe but not a flex liner. Light wall is to thin and the hole would quickly enlarge. And drilling a 1/4" hole in heavy wall would compromise the structure of the liner

Since the liner is UL listed and wasn’t tested with a damper, and the insert is also UL listed and has not been tested with a damper, wouldn’t that be unacceptable?

 

[bholler]

Since the liner is UL listed and wasn’t tested with a damper, and the insert is also UL listed and has not been tested with a damper, wouldn’t that be unacceptable?

Like I said you can't put a damper in a liner.

 

[webby3650]

@bholler @webby3650 <- Both of these guys have done that.

I’ve never put a damper on an insert. Thanks for thinking of me though!

 

[bholler]

I’ve never put a damper on an insert. Thanks for thinking of me though!

How do you address excessive draft on inserts? Not trying to argue just looking for more ideas.

 

[webby3650]

How do you address excessive draft on inserts? Not trying to argue just looking for more ideas.

We just haven’t really ran into this situation. I’d like to have a decent solution though if it the situation arises.

 

[bholler]

We just haven’t really ran into this situation. I’d like to have a decent solution though if it the situation arises.

A damper is the best solution I have found. I know some guys have had success limiting the intake but I found it works best to control the draft.

 

[jetsam]

I’ve never put a damper on an insert. Thanks for thinking of me though!

Hrmmm, my bad. Someone else here has, I guess I must be misremembering.

Increasingly common as the years march onwards...

 

[webby3650]

A damper is the best solution I have found. I know some guys have had success limiting the intake but I found it works best to control the draft.

So you do put dampers in the liner connected to inserts?

 

[bholler]

So you do put dampers in the liner connected to inserts?

No not in the liner as I said before. I have put them in a section of rigid stainless pipe though.

 

[begreen]

No not in the liner as I said before. I have put them in a section of rigid stainless pipe though.

Pics or it didn't happen.

 

[chazcarr]

I just need to reduce my draft somehow. I saw that the Ashford kind of has a damper right behind the catalyst, but it is rigid in place. You open the damper by opening the bypass. Controlling the air intake doesn't really work since the stove controls its own air intake.

I'm thinking that a tighter house, more insulation and new windows is the only thing I can do.

 

[bholler]

I just need to reduce my draft somehow. I saw that the Ashford kind of has a damper right behind the catalyst, but it is rigid in place. You open the damper by opening the bypass. Controlling the air intake doesn't really work since the stove controls its own air intake.

I'm thinking that a tighter house, more insulation and new windows is the only thing I can do.

What is your draft measurments? Tightening the house up will not change the chimneys draft unless you go to extremes. And in that case you will end up with other problems

 

[John B]

On my stove, secondary air has the same source as primary.
Controlling intake air made a big improvement.
How far down do you close the oak?
I'm amazed at how little of an opening is needed.

I covered the primary down to a slit that is probable the size of 3 toothpicks layed side by side. Maybe I will close it down a bit more. It would be difficult to add a length of stove pipe for the damper, although the mfg of the stove as advised a damper would be acceptable. I'm going to pull the surround off this weekend take some measurements to see if I can find a way to get a damper in there.

I'm getting pretty decent burns, last night I loaded at 11:30PM and when I got downstairs at 7:00 cat temp was 550 and there was still a nice orange glow in the fire box. Outside temp was 15F and I had the primary air open only about 1/8", house temp was 70F. I gave it some more air and headed off to work, leaving it for my wife to do the reload a little later on.

 

[velvetfoot]

Is getting a brush past it for cleaning going to be a problem?

 

[webby3650]

I covered the primary down to a slit that is probable the size of 3 toothpicks layed side by side. Maybe I will close it down a bit more. It would be difficult to add a length of stove pipe for the damper, although the mfg of the stove as advised a damper would be acceptable. I'm going to pull the surround off this weekend take some measurements to see if I can find a way to get a damper in there.

I'm getting pretty decent burns, last night I loaded at 11:30PM and when I got downstairs at 7:00 cat temp was 550 and there was still a nice orange glow in the fire box. Outside temp was 15F and I had the primary air open only about 1/8", house temp was 70F. I gave it some more air and headed off to work, leaving it for my wife to do the reload a little later on.

I guess I’m not sure what you think the problem is then? That’s pretty good considering the temps, inside and out..

 

[John B]

Agreed, after thinking about it more I'm not sure how much better I can do, but I would like to get more control over the burn especially when it is colder or windier outside.

 

[ShawnLiNY]

Agreed, after thinking about it more I'm not sure how much better I can do, but I would like to get more control over the burn especially when it is colder or windier outside.

Any possibility of adding one of these before the flex pipe than making linkage to pass through surround?

 

[bholler]

Any possibility of adding one of these before the flex pipe than making linkage to pass through surround?

It needs to be stainless