Location of secondary air intake(s) on Lopi 1750

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DBoon

Minister of Fire
Hearth Supporter
Jan 14, 2009
1,487
Central NY
Can anyone tell me where the secondary air intakes are on the Lopi 1750? There is no information in the manual.

Since I know I will get the question "why do you need to know this", I will answer it in advance. The stove breathes easy and there is a 28' chimney straight up (with a damper). It gets up to 800 degrees stovetop no matter how fast I throttle the primary air down, and the damper helps only marginally. I need to experiment a bit with limiting secondary air in this installation.
 
Not sure, but it's probably at the center rear or bottom of the stove. Alternatively, it might take 2 key dampers in the flue to reduce the draft sufficiently or maybe a more restrictive top cap.
 
Hi begreen, I see two sets of two 3/16" or so holes on the bottom of the stove - they look machined with some precision. I am suspecting that those are the secondary air intakes. I will experiment with partially blocking these off once burning season begins.

I'd hate to mess with the top cap (experimentally) on a chimney of this height with the roof pitch I have...

I've been given advice before on adding a second key damper. Given how restrictive the first one looks when closed, I'm shocked that just one isn't enough. But I might get there at some point, depending on how the next experiment goes.
 
Hi begreen, I see two sets of two 3/16" or so holes on the bottom of the stove - they look machined with some precision. I am suspecting that those are the secondary air intakes. I will experiment with partially blocking these off once burning season begins.

I'd hate to mess with the top cap (experimentally) on a chimney of this height with the roof pitch I have...

I've been given advice before on adding a second key damper. Given how restrictive the first one looks when closed, I'm shocked that just one isn't enough. But I might get there at some point, depending on how the next experiment goes.
I think that most key dampers permit about 25% air passage when fully closed. If the chimney is really pulling hard then a second damper may be in order, especially during very cold weather.
 
I tried exactly what you want to try but on a Lopi Freedom with a 29' chimney. I had very minimal success restricting the secondary air, the burn time increased but the stove smoked more and the glass accumulated a lot more soot. I believe the 1750 is a fixed secondary where the Freedom is adjustable but Tied the the primary air control. I used foil tape on that with to block the secondary inlet off it . The inlet on low was 0.375"x2.5" I blocked it down to 0.1875" x2.5". That gave me the desired burn times but It was to hard to control. I installed a damper it was much better but still not 100% happy with the stove. Here is a link to my thread on damper install
 
Thanks for the feedback, john26. I already had a damper installed, and don't really have room for an accessible two dampers. It turns out the holes I thought might be for secondary air intake were gnurled inserts for installation of a pedestal or something else. I can't seem to locate the secondary air intakes. I suspect they might be hidden on the sides of the stove, underneath the jacketing. So I am going to experiment with plugging the two inlets (one on each side) a little bit and see what happens.

I'm also installing an outdoor air kit this weekend and will connect it to the stove. I brought a four inch pipe through the wall with a reducer to 3" for installation of the flexible duct to the inlet connection. I've put a small key damper in the 4" primary air pipe, so we'll see if that gives me more control over the burn as well. I'm also adding the blower kit to the stove to try to have more ability to get heat off the stove when it gets really burning hot.

Cold weather is starting to arrive, so I should be able to test everything out pretty soon.

Stove burns well, it just has little fine control in this installation, especially with very cold temperatures. Once it gets going it just goes goes goes. I'm hoping the ability to reduce the primary air with the outdoor air kit will help a little bit.