Blaze King King vs Green Mountain 80

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NEKGirl

New Member
Jan 5, 2025
3
Vermont
Hey all!

I am planning on the purchase of a wood burning stove as I would like to move to predominately heat by wood. I am considering the Blaze King King 40 or the Green Mountain 80. I am aiming for a beast with long burn times and a larger fire box. I haven’t seen many head to heads posts between the BK40 and GM80 and am curious if one over the other is preferable or if I’m missing a stove that should be on my radar.

I realize the Blaze King King 40 has an 8” flue vs the 6” Princess. I have considered the Princess in my search. Are there any considerations to take into account in flue sizing besides price?

Currently:
Located in Northern Vermont in the mountains.
1600 sq ft main floor
ICF construction
9 ft ceilings, open living/kitchen area
French doors connected to the open kitchen/living area
65” window on the Northwest side
Ceiling fan near where the planned stove will be.
Currently radiant heating with propane.

I’m planning to position the stove in the living room very near the 65” window.

Other considerations:
I do have an unheated 800 sq ft unfinished second floor. An open staircase in the main living area ascends to it with a temporary insulated hatch in place until we finish off flooring, insulation, radiant heating, and walls. The future space will have 8ft ceilings.
 
The Princess should suffice and it will perform better, especially during the shoulder seasons. The BK stoves are true catalytic with thermostatic regulation. They are quite different from the hybrid GM stoves. Aesthetically, the Sirocco or Ashford would also do the job and be a bit easier on the eyes.

The main issue will be getting heat out of the stove room and into the main living area and kitchen. What is the size of the stove room? Is there a possibility of placing the stove in the open living/kitchen area? Can you post a floorplan sketch?
 
They’re going to want really dry wood. Did you put your wood up last year?
 
How much propane do you use 1. Per month, and 2. I'm your coldest day?
 
Here’s a super rough diagram of the open living/kitchen room. The purple X is where I plan to put the stove nearest the 65” window labeled W. The room itself is 310” x 248” not including the connecting hallways to the bedrooms.

I use about 40 gallons of propane per month. We are averaging days with highs in the 10’s and lows in the negatives. I have seen double digit negatives already this season.

[Hearth.com] Blaze King King vs Green Mountain 80
 
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With the ICF walls the heating needs are low. The main space is only around 540 sq ft. A smaller stove will heat the main area easily. The bedroom area will need some convective assistance in order to get the heat there. It looks like the Ashford or Sirocco 20 would work, even including upstairs. I think the GM80 would drive you out of the place. It's minimum output is too high, even with the upstairs finished it would be too much heat on its lowest setting for most days.
 
To reach the same conclusion as above, 40 gallons of propane contain 40*91,500 = 3,660,000 BTUs.
With an efficiency of 90% for propane heating, you put about 3,300,000 BTUs in your home in a month.
That is about 110,000 per day (average, not max at coldest weather).
That is less than 5,000 BTUs per hour.

Don't go big on the stove.
A BK 20 model would still put out more than that in it's minimum setting,.so you'd still need to do intermittent smaller fires, i.e. a heat pulse and the glide down in home temps before the next fire.

Of course during the coldest days and with the upstairs taking in heat that could quadruple, but 20,000 BTU per hour is easily met by the BK 20 models.
 
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Gotta love super insulated homes. That's what I came up with also. With the upstairs finished it might go up to 8,000 BTUs/day which is close to the bottom end of the BK 20 series. There will be some open windows occasionally, but nice on the days when the temps drop below 20ºF. Regardless of stove choice, plan on having an outside air intake for it.
 
Being in a corner, are you able to bring in fresh air through the rear wall or below the hearth? Newer tighter homes are a challenge at times.

BKVP
 
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Being in a corner, are you able to bring in fresh air through the rear wall or below the hearth? Newer tighter homes are a challenge at times.

BKVP
In the corner there’s about 48” of wall space on the exterior wall before the window edge. I think I should have enough wall space to rough in an exterior air kit to mitigate how well sealed the house is.
 
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In the corner there’s about 48” of wall space on the exterior wall before the window edge. I think I should have enough wall space to rough in an exterior air kit to mitigate how well sealed the house is.
Ok, just keep the F/A duct below height of stove firebox floor. @Highbeam inspired our corner, raised hearth to run fresh air under hearth and out side wall.

BKVP
[Hearth.com] Blaze King King vs Green Mountain 80
 
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I love our BK King.

18 hr overnight burns with Fir, keeps the house at 65 which is the temp we want. About a quarter of our wall area is windows and we have 11 foot ceilings. None of the drywall is up yet so the attic is open to the main level. It's a huge volume of air to heat. The walls and rafters are spray foamed but I still need to air seal the doors and windows and lots of cracks where the framing comes together and you can see daylight. I figure it's as leaky as a standard house at this point.

This started out as a "Go Big" comment but I can see why others are saying you don't need a huge stove. Once I finish our house we might not need the big tank.

The King fits in our space and I like the big black box design that others criticize, it matches the black glass. I only put the amount of wood inside that I need to make it to the evening reload and then pack it for overnight burn. Wood is our only heat source right now and the King got us through Winter last year when we had a week of -15F temps. I like having the ability of high heat output and still making it through the night without reloading. I also like the 24 hr burns I get when it's 35F outside. I can always turn the thermostat down further or add less wood if needed.
 
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I will throw out a heatpump for when you don’t need much is super convenient. Then once it’s cold enough you can go to 24 or 12 hour reload cycles.

With a heatpump I would not rule out some Like a pacific energy T5 (maybe T6?).
 
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A heat pump is a great suggestion and should be considered. I have one and use it. Zero ambiance though.

I do not think that the T5 or T6 can go sufficiently low, even for a cold-weather doubling of the current average BTU need AND doubling that again by having the upstairs open. That still is only 20,000 BTUs per day. You can do small fires in a bigger stove. But running that bigger stove always with smaller fires (as I think will have to happen) suggests to me a smaller stove is more appropriate. I think the T4 would then be better if a good quality tube stove is desired.
 
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