PreFab Fireplace to Wood Stove Insert Options

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sarasbluegroove

New Member
Nov 12, 2022
4
Rhode Island
I have a Sears "Prefab built in mobile home fireplace" in my living room (model 155.847201, couldn't find online anymore). We came into a lot of wood from some trees that were professionally taken down, and we've been slowly splitting and stacking it ourselves. We couldn't stomach the $600/month oil bill we had last year, and it will only get worse. We had intentions of putting in a woodstove insert, but after starting to look for quotes, this doesn't seem like an option. No installer will touch a prefab with an insert. What is the best option?

We could potentilaly do a freestanding wood stove, but i'm not sure what kind work would have to be done to the chimney to ensure it's capable of the heat from the woodstove. I don't want a woodstove because our living room is already small, we don't have the space, or even a hearth. Everything on the inside of the house is fake mantle/brick. I would want to redo all of that with stone or tile facing.

Could we demo the existing prefab and install an insert? Or would it be too costly to essentially install a new masonry fireplace just to install an insert? I want an insert for space concerns. The prefab is through our garage, so very accessible on the backside.

Currently this Prefab unit does not give off much heat at all. It kept our living room at about 65F during the dead of winter when we ran out of oil. We have to keep the doors wide open if we want any heat from it, which is a hazard with logs falling out.

I'm at a loss of what to do. All the intallers want us to tell them what we want, they don't want to offer advice or best options for our situation. Any advice or ideas would be appreciated! Thank you. (see attached picture of living room and fireplace)

PXL_20221108_213252041.jpg
 
I have a Sears "Prefab built in mobile home fireplace" in my living room (model 155.847201, couldn't find online anymore). We came into a lot of wood from some trees that were professionally taken down, and we've been slowly splitting and stacking it ourselves. We couldn't stomach the $600/month oil bill we had last year, and it will only get worse. We had intentions of putting in a woodstove insert, but after starting to look for quotes, this doesn't seem like an option. No installer will touch a prefab with an insert. What is the best option?

We could potentilaly do a freestanding wood stove, but i'm not sure what kind work would have to be done to the chimney to ensure it's capable of the heat from the woodstove. I don't want a woodstove because our living room is already small, we don't have the space, or even a hearth. Everything on the inside of the house is fake mantle/brick. I would want to redo all of that with stone or tile facing.

Could we demo the existing prefab and install an insert? Or would it be too costly to essentially install a new masonry fireplace just to install an insert? I want an insert for space concerns. The prefab is through our garage, so very accessible on the backside.

Currently this Prefab unit does not give off much heat at all. It kept our living room at about 65F during the dead of winter when we ran out of oil. We have to keep the doors wide open if we want any heat from it, which is a hazard with logs falling out.

I'm at a loss of what to do. All the intallers want us to tell them what we want, they don't want to offer advice or best options for our situation. Any advice or ideas would be appreciated! Thank you. (see attached picture of living room and fireplace)

View attachment 302580
Your options are a new high efficiency prefab unit with new chimney.

Tear out the prefab and install a freestanding stove with new chimney.

Or tear it out build a masonry fireplace then install an insert.

The cheapest option is most likely a freestanding stove. Followed by a new prefab. Then a fireplace and insert.
 
The flue for the existing prefab fireplace likely will not be correct for a new stove or EPA zero clearance "fireplace" that puts out real heat. If it runs through wood chase it usually needs to be the expensive insulated type. That was the major part of our conversion from crappy prefab to ZC fireplace. We did ZC vs freestanding stove for space reasons.

Some people call ZC fireplaces "inserts" but technically an insert goes into an existing fireplace. The ZC unit can go right up against studs like the prefab fireplace did.
 
If space is constrained then a complete removal of the existing Sears ZC and creation of an alcove in that space for a freestanding stove is another option. The TV would need to be moved as the alcove would be open to the ceiling. It is possible to build an alcove that is 100% non-combustible, so that the stove sat inside with the tv above, but that would require careful planning and stove selection.
 
Thank you so much! Can you please educate me on what a zero clearance is? It sounds like it could be an efficient solution for us. How much heat could it put out? We are not intending to heat our whole house, we have minisplits in the 2 upstairs bedrooms that I'm hoping can do the job upstairs, so it would just be our first floor that the current one minisplit is already struggling to heat (3 bedrooms, kitchen and living area), although we will probably install small door fans to try to get some heat upstairs and into the bedrooms. We would be looking to mostly use the firplace and minisplit for heat, with the assist of oil furnace if needed. Our total square footage is 1900, with maybe 1000-1100 downstairs. Thanks again!
 
Here's an example: https://www.woodlanddirect.com/osburn-stratford-ii-zero-clearance-wood-stove-fireplace/617143.html I have what was the budget version of that, a Flame Monaco, which is no longer made. SBI makes a bunch of stove brands.

Basically an EPA ZC fireplace is a stove in a box which keeps the heat from the studs its mounted to.

One drawback is that it has a fan. I asked the manufacturer if I should be concerned when the power goes out and they said no, but I let the fan run when using the stove and do not keep a fire in it when the power is off since we shut the generator off at night. I figure if they put the fan there I should use it. It's kind of noisy in our quiet house. Another drawback is that its harder to replace the unit with another one of a different make/model than it would be with a free standing stove. If I had the space I'd have gone with a freestanding stove.

Our 75k btu rated unit is able to heat our not very well constructed 1980s 2500 sq ft two story house down to the mid 30s, which is about as cold as it gets here. Probably not a very good comparison to your circumstances but there it is.
 
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I've been doing some reading on the rear vent wood stove idea. How close to the fireplace could we set the stove to save on space? I was thinking of having a black removable cover behind the stove. Is there any reason we couldn't get it backed up to that as close as possible? What rear venting stoves would you recommend for the least amount of space but can still heat our first floor (~1000 sq ft)? I'm trying to evaluate costs. How much cheaper would it actually be for the rear venting stove than a ZC fireplace? Either option would be professionally installed. Thank you!
 
Rear-venting a stove into the fireplace is a possible option. The determinants would be the lintel height of the fireplace, a stove whose flue collar height is below the lintel height, and whether the flue diameter is large enough to accommodate an insulated liner.
 
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I will eventually get an installer out to take a look. But to give you an idea of the back of the fireplace, it is a firebox in my garage, the support system built by 2x4 wood. The chimney goes straight up through my garage roof along the wall, but completly open to the garage (no insulation). Does that impact options at all? I have no idea what kind of "chimney pipe" I have, and if it would need to be upgraded to a different material. I am attempting to supplement (or completly replace) our oil furnace with the electric minisplits and the fireplace. I have a ton of free wood ( most likley years worth if burning 24/7). I keep reading about the chimney with air cooled liners, etc. Does this still apply if i just have a metal pipe out in the open?
 
It depends what the final plan ends up being. Most likely the fireplace chimney would need complete replacement. The older fireplaces typically used chimney pipe that has a much lower temperature rating than required for a wood stove (if alcove) or for a modern EPA fireplace replacement.
 
I suspect that you will need to tear out the whole thing, install new class A chimney and then install the stove in an alcove type installation. I had a prefab fireplace installed in a house I purchased. The air cooled chimney that came with it was clearly not rated for a wood stove. Ripped everything out, put in class A and then set the stove up for an alcove installation. With this set up, the stove sits in the alcove and barely protrudes into the room, it meets all of the clearance codes. I would also suspect that outside air intake, might be desired. With my alcove all tiled and so on, it looks very nice.
 
I was in your situation having a useless prefab zc fireplace. I tore out the old zc and chimney and installed a pacific energy zc fireplace with new 6 inch flu. That was my cheapest option vs doing an alcove. The way companys make zc fireplaces these days they are very efficient. Mines perhaps the smallest size at 1.6cf fire box and heats my 1600sf house no problem
 
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