Set-up tips for Osburn Horizon

[MCasabonne]

Hi Folks - We're looking to install an Osburn Horizon in 2-year old home in the fall. The house is two-story 2,800 square-feet finished space, with unfinished basement and attic. We boxed in a space large enough to accommodate the stove on an interior wall dividing the first-floor kitchen and living area with a chase above that area through to the attic. Our local retailer recently visited the house to take measurements. I'm looking for advice on set-up. A few points:

-I've read that these stoves (Horizon and Valcourt Waterloo) perform better with an outside air kit (OAK), but also that it's important to be able to block or partially block the OAK for longer burn times. Can anyone recommend a user-friendly adjustable damper/register, or is everyone just going with the SBI OAK and SBI damper/register?

-The Horizon can be used with a fair number of 8" chimney pipe options. Our installer says "stove pipe is stove pipe." Keeping in mind our chase will run inside the home to a roof penetration (rather than in an uninsulated exterior chase), does anyone have any recommendations on which of the pipe options to choose?

-We'd like to connect the stove to our forced-hot air distribution ducts. Does anyone have recommendations on the requirements for a successful set up? Flexible or hard duct? Standard power in a blower, or go oversized? Connect as close to the plenum as possible, or closer to duct branches leading to rooms we'd like to heat?

-I've read the SBI forced hot air distribution kit is overpriced ($750), and that other manufacturers sell a better, quieter blower, for less money. It certainly looks from the description of the kit as though it would be possible to piece a custom kit together. Does anyone have recommendations on a particular blower?

- Finally, we'd like to install our Horizon about 20-24 inches from the floor, and build a floating hearth seat as our required hearth extension. To do so, we will have to construct the floating hearth seat of materials that meet the R requirements, and tie it in to the stove support framing. We're thinking of cladding the fireplace in durock and porcelain tile, and would make the seat to match. To do so, we'll have to "frame out" the seat, and are thinking of custom-welding a metal stud frame, with arms that tie into the stove support framing. Has anyone does anything like this? How did they build their floating hearth seat and anchor it to the stove support framing?

Thanks in advance for any advice. -Mary

 

[kennyp2339]

Not sure where home is located in the US, (its kind of important to get an idea of draft) but if the pipe is in a chase it needs to be class A, which generally is double wall insulated. Not sure the height your going to extend either (kind of important)
I agree that installing an oak is best for operation, unknown about the chimney info or home location or stove location in relation to the outside air source, generally if you further then 10ft you size up the pipe I believe from 3" to 4"

 

[begreen]

Stove pipe is not chimney pipe. And there are differences between different chimney pipes. The list of options for class A chimney pipe for this fireplace are broad, ranging from value line chimney to high quality. I would avoid the value line triple-wall chimney pipe and stick with the better lines. This is infrastructure, so best do it right. Ventis and Olympia are recommended and are good chimney pipe.

The governing factor for the hearth construction will be the distance from the door. The way it has been described it sounds like it will float in front of the stove, cantilevered out from the wall. Is that correct? Do you have drawings? Will the hearth have legs? As described, think of the hearth seat as the "floor" described in the manual. The hearth extension table describes the insulation requirements for protection.


The area below the hearth seat should also have a non-combustible covering like tile or brick in case embers fall down on it.

 

[ericm979]

The Horizon is very similar to my Flame Monaco, but the next size larger fire box and EPA II instead of I.

I have the factory OAK and the valve that comes with it. I can detect no difference in stove performance with the valve closed.

There's not a lot of control of the heat output. Once it's burning well, closing the air control all the way makes the stove hotter. I think part of that may be my 35' flue but it's also how these non cat EPA stoves work. There has to be enough secondary air to burn the smoke. So there is a minimum air flow into the stove.

It makes the stove less useful for shoulder seasons where I don't need the full output.

 

[MCasabonne]

Thank you for your replies. I agree that, as this is infrastructure, we want to make wise choices, and we are willing to pay for the quality materials for the job.

We are in upstate New York, about an hour north of Albany.

The gable ends of the house face east/west. The stove will be nearly under the ridgeline, so roughly 15' from the south and north wall, and about 15' in from the east gable end of the house.

We'll be installing the stove about 24" above the floor (with the floating hearth seat 8" below that stove, the seat will not have legs) on the first floor. We have 9' ceilings on the first floor, 8' ceilings on the second floor, and we can stand up in our attic. So I'd figure chimney height of about 27 feet. The chase begins above the stove, but it is to one side of the stove, not directly above the center of the stove, so we will need at least one offset to bridge the distance between the center of the stove and the start of the chase.

With that in mind, I'm hearing Venta and Olympia as good options for Class A chimney pipe, 4" pipe for the OAK, 20" hearth seat with R value of 1, and expect the stove to be hot. I'll take a few pictures of the set up and post them later today.

 

[kennyp2339]

Thanks for the info, I understand the setup a bit better, Upstate NY to me suggest that you'll be burning in colder conditions most of the time, then someone lets say in Southern NJ, a 27ft chimney is rather tall, using 8" pipe, your flowing some serious volume which only increases the colder its outside vs the warmth of the stove on the inside.
I'd see as part of the chase build near the stove collar, having a damper installed that is operated by cables, along with a flue probe to be mounted on the side, that way you can tell by your flue gas temp how hard the unit is running (think when the air control is turned off, secondary combustion on its own feed still occurs) the only way to turn it down is to control the draft or block the secondary inlet which isnt feasible for a finished unit like yours.
Like what others have mentioned, trying to control the air inlet on the oak side isnt really effective.

 

[MCasabonne]

Here's a picture of the wall where the fireplace will be installed, take from the northeast corner of the living room. The fireplace will be on the wall in front of the rocking chair. Behind the rocking chair, we will build in a nook for wood storage. The floating hearth seat will run the full section of that wall. We expect the vent pipe for the OAK will run in the basement joist bays to the south wall of the house.

 

[MCasabonne]

Thanks for the info, I understand the setup a bit better, Upstate NY to me suggest that you'll be burning in colder conditions most of the time, then someone lets say in Southern NJ, a 27ft chimney is rather tall, using 8" pipe, your flowing some serious volume which only increases the colder its outside vs the warmth of the stove on the inside.
I'd see as part of the chase build near the stove collar, having a damper installed that is operated by cables, along with a flue probe to be mounted on the side, that way you can tell by your flue gas temp how hard the unit is running (think when the air control is turned off, secondary combustion on its own feed still occurs) the only way to turn it down is to control the draft or block the secondary inlet which isnt feasible for a finished unit like yours.
Like what others have mentioned, trying to control the air inlet on the oak side isnt really effective.

Yeah, I hear you. Are cable operated flue dampers commercially available? And if so, can you recommend one?

I found this option for an OAK damper/register. It's for 5" pipe, but more troubling to me is that it's not adjustable -- it's on or off. And it looks like a flimsy mechanism.

The idea of a flue probe is new to me and sounds smart. I'll look that up!

We will be working with a reputable stove installation store (I don't hold the installer's offhand comment that "stove pipe is stove pipe" against him. It was an offhand comment, I'm sure he'll have a more considered reply when we're going through the quote), but I want to be as informed as possible to minimize my regrets once everything is installed and sealed up.

 

[MCasabonne]

Thanks for the info, I understand the setup a bit better, Upstate NY to me suggest that you'll be burning in colder conditions most of the time, then someone lets say in Southern NJ, a 27ft chimney is rather tall, using 8" pipe, your flowing some serious volume which only increases the colder its outside vs the warmth of the stove on the inside.
I'd see as part of the chase build near the stove collar, having a damper installed that is operated by cables, along with a flue probe to be mounted on the side, that way you can tell by your flue gas temp how hard the unit is running (think when the air control is turned off, secondary combustion on its own feed still occurs) the only way to turn it down is to control the draft or block the secondary inlet which isnt feasible for a finished unit like yours.
Like what others have mentioned, trying to control the air inlet on the oak side isnt really effective.

I found a picture of this 8-Inch Drop In Damper. Is this more or less what you're thinking of? I'm not convinced its the best design (I can see that spring deteriorating pretty quickly). And how on earth does the control system pass through the chimney pipe without breaching the wall? I think I don't understand : )

 

[ericm979]

Yeah, I hear you. Are cable operated flue dampers commercially available? And if so, can you recommend one?

I found this option for an OAK damper/register. It's for 5" pipe, but more troubling to me is that it's not adjustable -- it's on or off. And it looks like a flimsy mechanism.

The idea of a flue probe is new to me and sounds smart. I'll look that up!

We will be working with a reputable stove installation store (I don't hold the installer's offhand comment that "stove pipe is stove pipe" against him. It was an offhand comment, I'm sure he'll have a more considered reply when we're going through the quote), but I want to be as informed as possible to minimize my regrets once everything is installed and sealed up.

View attachment 310676

It's adjustable between on and off. That's the one I have. The knob has detents and there's no spring anyhow so it'd stay in position without them.

But you adjust the stove's air supply with the lever on the stove.

I wish I'd had room for an alcove and a regular stove rather than a ZC fireplace. The ZC needs the fan running to effectively heat the space, so I can't run the stove during a power outage unless I'm running the generator. The fan while not super loud, isn't exactly quiet either. We live in a very quiet area. By spring I'm tired of the noise.

It'd be a lot easier to replace a standalone stove should it have a problem or I wanted to make a change. Replacing the ZC would probably mean reconstructing the surround to a different size.

 

[MCasabonne]

It's adjustable between on and off. That's the one I have. The knob has detents and there's no spring anyhow so it'd stay in position without them.

But you adjust the stove's air supply with the lever on the stove.

I wish I'd had room for an alcove and a regular stove rather than a ZC fireplace. The ZC needs the fan running to effectively heat the space, so I can't run the stove during a power outage unless I'm running the generator. The fan while not super loud, isn't exactly quiet either. We live in a very quiet area. By spring I'm tired of the noise.

It'd be a lot easier to replace a standalone stove should it have a problem or I wanted to make a change. Replacing the ZC would probably mean reconstructing the surround to a different size.

That's useful feedback, thank you! Our installer recommended putting the blower in the basement to reduce the noise. I've also read that there are cheaper, quieter fans on the market that you can piece together with parts to replace the SBI blower kit. We'll have a similar issue with wanting to use the stove during power outages, so I definitely want to think that through. We have a designated generator panel, but yeah, would prefer to avoid the noise. We recently had solar panels installed, but battery backup would've doubled the cost, so we skipped for now.