Damper for better efficiency on a Lopi

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GrumpyOldMan

Member
Nov 7, 2019
34
NE Indiana
Hello All!

I am on my second year of wood burning with a Lopi Endeavor. ( First wood stove)
All of the folks here have helped me tons!
Of course I do have another question, about efficent burns.

The stove was installed by my local dealer, 6" double wall inside and the good triple wall stuff on the outside.
Not Sure of the total Flue Length, over 20 feet maybe 23. It has a very strong draw anyways.
I installed a Condar fue temp gauge (Probe type) 25" up from the collar.

I have struggled to get the stove top temp and the flue temp close, best I can do is about 200
to 250 dgrees (hotter in the flue than on the stove top).
On fire up I usually see 900 to 1000 degrees on the Condar when the stove top gets to 600 degrees.
I then choke it down in stages und usually end up around 450 degrees on the stove top with the Condar showing about 650 to 700 degrees.
with the air open about 25% to 30%. I can get about 5 to 6 hours of heat like that until the stove top is around 150 degrees.
My wood usually checks between 15% and 21% on a fresh split. (I consider it dry enough) Mostly Ash, some Beech and Oak.

My question is Can or Should I install a flue damper on this stove for more effecient control of the air flow and keep more heat in the stove?

Thanks ahead of time.
 
the good triple wall stuff

This is not the good stuff. The good stuff for class A chimney is insulated double wall stuff.

I recently had a similar problem with flue temperatures too high and short burns. I added a key damper and was able to cool the flue gasses 100-200 degrees for the same stove temperature and noticeably increase burn times. An hour or two is a big deal when you're used to getting 4-5 hour burns!

Lopis have always had a reputation as a hot burning stove. It's very easy and cheap to add a key damper and leave it open if you don't get any benefit. No harm done.
 
You Are correct... it is Excel Class A chimney. and Excel Double wall on the inside.

Thanks , That is exactly what I was thinking... if it didn't help, just leave it wide open.
 
I have a problem keeping the pipe temps down, when my wood could use more seasoning.
The better the wood, the easier it is to control.
 
Those temps sound pretty decent, you can try a damper but I would expect a night and day difference. Just remember if you do install a key damper in dvl, put it in so you can access it easier to scrub the plate with a wire brush during regular chimney cleaning, the damper will get buildup over time.
 
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@brickie that looks good to, I'm suspect on the OP since he's using two different methods of gathering temps, a stovetop thermometer isnt quite exact since it sits on top of the unit, but then gets flue measurements from a probe thermometer which is exact since its directly in the plume, where as a pipe thermometer will just take the outside skin readings. I'm sure if you had a probe thermometer you would be seeing almost the same readings as the OP.
 
You Are correct... it is Excel Class A chimney. and Excel Double wall on the inside.

Thanks , That is exactly what I was thinking... if it didn't help, just leave it wide open.
Well I did have a Key (Manual) Damper last Summer.I can tell you I have burned about 20% less wood this year, while maintaining about 72 to 73 degrees upstairs. Of course there could be a variance in outside Temps.
I run the stove as I normally would but sometimes I use the the Flue damper in addition to the Air Intake.
It has been working well for me.
House is about 2000 sq ft.
Lopi Endeavor is Downstairs with an open stairwell.
Running the stove top around 500 to 600 degrees cruising, the Condar probe is about 24" up and when the stove top reads 500 , the Condar reads about 750.
I have the stove and chimney inspected and cleaned every summer. So far , nothing more than about a half of a cup of "Fly Ash" (What they call it).

So It is working for me .
 
I believe a key damper would probably benefit most stoves operating on chimneys of 20 feet or more. When I put a manometer on my pipe, and saw it was sucking 3x harder than the "maximum draft" spec of my stove, it became clear as day that I needed one.

Hey bholler, is it standard practice for a pro installer to check draft on all new installs?
 
Well I did have a Key (Manual) Damper last Summer.I can tell you I have burned about 20% less wood this year, while maintaining about 72 to 73 degrees upstairs. Of course there could be a variance in outside Temps.
I run the stove as I normally would but sometimes I use the the Flue damper in addition to the Air Intake.
It has been working well for me.
House is about 2000 sq ft.
Lopi Endeavor is Downstairs with an open stairwell.
Running the stove top around 500 to 600 degrees cruising, the Condar probe is about 24" up and when the stove top reads 500 , the Condar reads about 750.
I have the stove and chimney inspected and cleaned every summer. So far , nothing more than about a half of a cup of "Fly Ash" (What they call it).

So It is working for me .
I forgot to say THANKS to Everyone on this site... I have learned about everything right here. Especially begreen.... A tremendous help.
Thanks to all!!!
 
I believe a key damper would probably benefit most stoves operating on chimneys of 20 feet or more. When I put a manometer on my pipe, and saw it was sucking 3x harder than the "maximum draft" spec of my stove, it became clear as day that I needed one.

Hey bholler, is it standard practice for a pro installer to check draft on all new installs?
I know they did not use a Manometer on mine, but I Think I have 24' plus of Chimney, and It Draws like a freight Train.
My Installer ?Inspector/Dealer said I would be OK with the Damper,even though the Lopi Endeavor is not designed for that.
Because of the large Draft.
 
I believe a key damper would probably benefit most stoves operating on chimneys of 20 feet or more. When I put a manometer on my pipe, and saw it was sucking 3x harder than the "maximum draft" spec of my stove, it became clear as day that I needed one.

Hey bholler, is it standard practice for a pro installer to check draft on all new installs?

Lol. I'd say nope. Not all pro installers are good installers...

And regarding a damper "standard" above a certain stack height, this depends also on elbows and horizontal runs.
 
I believe a key damper would probably benefit most stoves operating on chimneys of 20 feet or more
And many other 2020 stoves on an even shorter chimney depending on the particular installation and local conditions.

Hey bholler, is it standard practice for a pro installer to check draft on all new installs?
It is his job to install to regulations, even if he knows there is a better solution based on what his own eyes, experience and data tells him.
 
If the flue temps are getting up to 900-1000º the stove's air is not being shut down early enough. That's wasting heat. Try starting the incremental shut down of the stove air (pipe damper open) at around 600-700º flue temp. The stove temp will come up a little slower, but the burn time should increase and the stovetop should hold temp longer.
 
If the flue temps are getting up to 900-1000º the stove's air is not being shut down early enough. That's wasting heat. Try starting the incremental shut down of the stove air (pipe damper open) at around 600-700º flue temp. The stove temp will come up a little slower, but the burn time should increase and the stovetop should hold temp longer.
Are you running a 2020 stove?
 
His signature says 2019 Endeavor. Our stove is a 2008 T6. I helped put in a 2020 T6 at a neighbors. They run it pretty much the same way we do.
 
Just asking if you are personally running a 2020 EPA certified stove. I'm guessing his 2019 stove is up to 2020 EPA regulations.
The 2019 Endeavor was the last model prior to the new regs. There were several notable changes made in the 2020 model going forward. A fourth secondary tube was added and the baffle was changed from firebrick to fiberboard and an insulation blanket. I've run the earlier Endeavor a few times. Easy stove to operate.
Nice edit.
I didn't understand the question. It was an afterthought.
 
The 2019 Endeavor was the last model prior to the new regs. There were several notable changes made in the 2020 model going forward. A fourth secondary tube was added and the baffle was changed from firebrick to fiberboard and an insulation blanket. I've run the earlier Endeavor a few times. Easy stove to operate.

I didn't understand the question. It was an afterthought.
Very well, sorry for the intrusion, carry on.