stove/insert to get and heat flow for floor plan

[oaky]

I would like to get a wood stove before next winter and am trying to plan appropriately and am trying to think about how the heat can spread through the house. Attached is a floor plan. I currently have an open hearth fireplace that I have never lit a fire in but was inspected when I bought the house. As can be seen from the floor plan, the chimney is in the interior of the house, but it is facing into a room rather than being centralized. There is a basement that I don't care about heating. But I do want to heat the upstairs as well. The stairway is 2 half flights connected by a landing. The upstairs floor plan looks similar to the one shown but instead of 4 open rooms has 4 closed bedrooms.

We currently have a natural gas furnace that is getting old. Part of the cost of getting a wood stove/insert will be paid by not having to preemptively replace the old furnace before next winter and also by possibly extending its lifespan by reducing its workload. We will replace it with a heat pump when it goes out and don't want that time to be an emergency situation which can also be costly.

I have an ERV that we run continuously and could put in an OAK through the basement although the ash dump is near the floor rather than the ceiling where the intake would be.

In my initial research I really like the idea of getting a Blaze King so I can do longer burns when using it as supplemental heat and also use the wood stove through more of the year. My other goal is to minimize pollution as much as possible. The PE32 might be my ideal stove, but I am assuming getting an insert will have the advantage of a cheaper install or working better with our floor plan.

I have read through other forum entires, but am looking for advice that is particular to my situation and floor plan- how to spread heat and what stove/insert seems appropriate. Thank you for any of your ideas and advice. This is a great site!
Sorry for the awful drawing of the floor plan. There is a fireplace in the upper left room of the diagram and a ceiling fan not far away.

 

[stoveliker]

I think that quite some heat will flow up the stairs.
If you add a fan on the ground in the lower doorway, blowing cold air towards the stove room, you can get a circuit of air flow going. To heat the right half of the floor.
The trick is to have the fan on the ground and blowing low, so you don't mix the cold air with warm.
If there are transoms in the hallways that might decrease the efficiency of moving the heat.
A transom in front of the stairs would decrease heat flow up. Not sure that's wanted or should be avoided.

How tall would the chimney be from insert connection to chimney cap?
You'd need to line it with a 6" liner, most likely it needs to be insulated for safety and code compliance.

 

[oaky]

Most of the ceiling is 9 feet tall. The hallway area by the stairs is about an 8 foot drop ceiling and there are beams (I think you are using the term transom) that go down to about 7 feet that air will have to duck under first before getting to the drop ceiling where it will be un-impeded in going up the stairs.

The chimney is pretty tall- going up through the 2nd floor and then through the finished attic space and out the roof. I can try to figure out a more exact measurement, but I thought that would be more of an installation detail.

 

[stoveliker]

Ok. You may need a key damper if your chimney is that tall; stoves are generally designed the pass EPA testing with a minimum draft equivalent to what a 15 ish ft chimney provides. You're likely above 20 ft. High draft makes it harder to control stoves, in particular stoves with unregulated secondary air.

Cat stoves can get fly ash sucked into the cat, clogging it.

A freestanding stove may be hard unless the fireplace is completely demolished. An insert may be easiest, though you'll depend on a fan to get enough heat out.

Fireplace dimensions would be needed to see what inserts would fit. (Others are more knowledgeable in this)
Stoves might need to be rear exit if they are not placed in front of the fireplace with a new thimble higher up. A BK freestanding stove may not work well in a fireplace that's too small.

If your ceiling is lower near the stairs, a fan on the ground there blowing towards the stove may work better. But the fan can be done later, if it's too cold on the right hand side of the home.

 

[oaky]

To push hot air upstairs there could be a pass through vent with fan from the fireplace room to the stair landing.

 

[stoveliker]

Generally it works better to move cold air. From the landing down to the stove room. It'll be replaced by warm air rising up the stairs.

But I think that enough will go up given the proximity of the stove to the stairs. I'd not make holes until you determine it's needed.

 

[oaky]

The hearth opening is 36" wide and 30" tall.
The firebox is 19" deep. It tapers from 36" wide at the front to 26" wide at the back.

The BK Sirocco 25 or Ashford 25 should work. The BK Princess 29 seems like it might just fit but I don't think we want the insert sticking out that much unless it makes a big difference with the heating effectiveness.

My chimney is probably around 30' tall. Does that just mean it needs a key damper installed?

 

[oaky]

Can someone tell me what these firebox vents are for?

 

[DuaeGuttae]

I can't say for certain, but my guess would be that it's an outside air intake. Is it a sliding metal plate going over a grate in a hole in your firebrick on the side?

Is it the aesthetics of the Princess insert that don't appeal to you, or is there another reason you don't want it to stick out too far? In previous homes when we had inserts, we chose deliberately to have non-flush inserts for the better heating performance. We still used fans to get the most heat, but we liked having part of the firebox exposed for more radiant heat and for times when the power was out.

The Princess insert also has a bigger and more square firebox than the Sirocco/Ashford insert, I believe, so it's easier to load. I have not used any of these inserts personally, though I have looked inside the Princess, so it would be good to double check with actual owners.

In our first home we had an insert in our basement, and it worked great. There was a beam between the insert and the staircase, though, and hot air definitely pooled up there. We used ceiling fans to push it down, and we did eventually cut some vents which worked in our situation, but I spent a few years with the insert investigating temperatures and airflow before we made that decision.

In our current home our stove is located in an open area on the main floor pretty near to the staircase that leads upstairs where there are four bedrooms in each corner off a central area. The stairs are what you describe as two half staircases connected by a landing. The heat flows up pretty well in our case. Using a blower does help to push the heated air, I believe.

 

[stoveliker]

At 30 ft people with freestanding stoves sometimes put 2 key dampers in.
You surely need one. That's not easy with an insert, but it's possible.

Too much draft will kill a cat because flame gets sucked in, it can also clog a cat with ashes, and can lead to overfires.
It's just harder to control a fire when the air flow is too strong.

As @DuaeGuttae says an insert that sticks out heats better. Especially when the power is out. Do make sure you have enough ember protection in front of the insert.

 

[oaky]

If the fireplace sticks out more than we need more ember protection and overall it makes it harder to use the space in the room. Will definitely think about it though, including if there are ways to re-arrange the room.

The ceiling fan that we already have seems like it could help push hot air under the beam so it can make its way up the stairs.

I can't say for certain, but my guess would be that it's an outside air intake. Is it a sliding metal plate going over a grate in a hole in your firebrick on the side?

Yes. There is one on each side of the firebox. I see a vent on the side of my chimney after it comes out the top of the house- it seems there is an OAK built in already!

At 30 ft people with freestanding stoves sometimes put 2 key dampers in

Actually I would say it is at least 33 feet. We do often have a lot of wind at times. Would the key dampers be dampers that I am supposed to manually adjust based on the conditions of the fire and the wind?

 

[stoveliker]

Yes, you'd need to open it fully before opening the door, and close it depending on weather and burning characteristics of the fuel.

 

[DuaeGuttae]

How big is the square footage of the two floors you are hoping to heat with the insert?

You mention having an ERV. Does that mean that you're pretty well insulated and airsealed?

I'm just thinking about the smaller versus larger Blaze King inserts. The size of the home and its insulation would be important factors to consider.

 

[BKVP]

Thank you for mentioning your desire to burn clean as possible. EPA stoves are very clean burning because we have test method M28R, with little variability as possible. To get the very best results, plan on storing the amount of fuel you will require for a season, perhaps two.
Cut, split and stack wood under a properly designed wood shed is a great beginning.

Purchase a moisture meter, learn how to use it (don't ever post a picture here with the needle being pushed against the grain, lest the engineers will release the Kracken).

If you plan on burning 3-4 cords per year, your wood shed, ideally can hold 6-8. Start this summer building a 2026-2027 winter fuel supply. And next year repeat the process, allowing fuel to dry upwards 2 years depending upon species being burned.

BKVP

 

[oaky]

Each floor is about 1000 square feet. I am trying to avoid heating the basement and there's also a finished attic space above the second floor, but I am not as concerned about providing heating for that. I did an energy calculation for the house for the purposes of getting a heat pump. It came to 65.65k BTU/hour. My current furnace can put out 100k BTU//hour and has a 92% efficiency. I will continue to do more to improve the energy efficiency of my house over time.

I do not intend to perform all my heating with the fireplace all year round. The fireplace though will allow us to not worry about over-sizing the heat pump and still be able to easily handle the coldest days of the year and provide a backup heat source both for when we transition to a heat pump or whenever or furnace/heat pump is offline or there is a power outage. If the fireplace is convenient to use, provides comfort, and I can figure out how to get the heat to circulate well, then I can use it as a regular heat source. Currently our second floor is always warmer than the main floor by a few degrees and it could certainly remedy that and also provide a warm heat source to warm up next to.