How to evaluate stoves

[cnapierala]

I have done a lot of reading regarding stove reviews but im having trouble understanding how to rank one stove vs the other.

Here are the 3 that im considering based on dealer availability etc.

MFGR	Model	Max Log length	Heating space	Max Output (BTU/HR)	Efficiency	Firebox size (CU FT)	Flue Size
Kuma	Wood Classic LE	18"	2400 - 3000	82000	79.4 HHV	2.5	6"
Regency	F3500	20"	1500 - 2500	88000	76 HHV	3	6"
Lopi	Endeavor II NexGen-Hybrid	19.5	2000	70,500	80 hhv	2.5	6"
Lopi	NexGen Liberty	24"	2500	63239	70 HHV	3.65	6

So im an engineer by trade and don't understand these numbers. How can a 3.65 cu/ft firebox with a 70hhv provide lower max btu than a 80HHV 2.5 cu/ft firebox.

So for instance if you took 1000 BTU x 80% x 2.5 vs 1000 BTU x 70% x 3.65 you come out quite a bit ahead on the 3.65cu/ft firebox.

Is my math bad or do i misunderstand? How can i best compare these?

For reference i have a 2000 sq foot area and live in Divide Colorado. We dont want to go on the light side of heat but really like the Lopi Liberty look and quality but not sure its enough heat.

Thank you,

Chris

 

[webby3650]

Because the government is involved! There are different test methods, which result in different results. It’s hard to follow. I’ll say this, Lopi is by far too dog on that list. They burn so nice and are very well made. If your dealer has blaze king, look closely at those. They have the best burn times in the industry. Considering your required heat requirements, burn times probably won’t be your concern as much as heat output. The Liberty is a monster heater, if you’ve got insulation, I can’t imagine you’d have any issues.

 

[cnapierala]

Because the government is involved! There are different test methods, which result in different results. It’s hard to follow. I’ll say this, Lopi is by far too dog on that list. They burn so nice and are very well made. If your dealer has blaze king, look closely at those. They have the best burn times in the industry. Considering your required heat requirements, burn times probably won’t be your concern as much as heat output. The Liberty is a monster heater, if you’ve got insulation, I can’t imagine you’d have any issues.

Thanks for the response. There is not a Blaze King dealer in the area within 2 hours unfortunately.

We want the stove to burn through the night but also want a lot of heat out of it. I love the Lopi Liberty but want to make sure im not making a mistake with the others.

 

[Highbeam]

I have done a lot of reading regarding stove reviews but im having trouble understanding how to rank one stove vs the other.

Here are the 3 that im considering based on dealer availability etc.

MFGR	Model	Max Log length	Heating space	Max Output (BTU/HR)	Efficiency	Firebox size (CU FT)	Flue Size
Kuma	Wood Classic LE	18"	2400 - 3000	82000	79.4 HHV	2.5	6"
Regency	F3500	20"	1500 - 2500	88000	76 HHV	3	6"
Lopi	Endeavor II NexGen-Hybrid	19.5	2000	70,500	80 hhv	2.5	6"
Lopi	NexGen Liberty	24"	2500	63239	70 HHV	3.65	6

So im an engineer by trade and don't understand these numbers. How can a 3.65 cu/ft firebox with a 70hhv provide lower max btu than a 80HHV 2.5 cu/ft firebox.

So for instance if you took 1000 BTU x 80% x 2.5 vs 1000 BTU x 70% x 3.65 you come out quite a bit ahead on the 3.65cu/ft firebox.

Is my math bad or do i misunderstand? How can i best compare these?

For reference i have a 2000 sq foot area and live in Divide Colorado. We dont want to go on the light side of heat but really like the Lopi Liberty look and quality but not sure its enough heat.

Thank you,

Chris

I too am an engineer. Most important is that those three parameters are garbage. They are marketing game figures meant to deceive.

What you’re looking for is firebox volume, efficiency, and range of available outputs. These three specifications are to be found nowhere but the epa certified wood stove list.

 

[webby3650]

Thanks for the response. There is not a Blaze King dealer in the area within 2 hours unfortunately.

We want the stove to burn through the night but also want a lot of heat out of it. I love the Lopi Liberty but want to make sure im not making a mistake with the others.

It’s one of the biggest stoves available with a 6” flue. If it won’t do it, none will without moving up to bigger stoves. Options are few, and not as attractive.

 

[cnapierala]

Can you expand on what your post? So basically im understanding that my evaluation should be firebox volume x HHV efficiency x ? - what do you mean by range of available outputs?

Thank you!

 

[cnapierala]

It’s one of the biggest stoves available with a 6” flue. If it won’t do it, none will without moving up to bigger stoves. Options are few, and not as attractive.

Thanks for your responses!

 

[Highbeam]

Can you expand on what your post? So basically im understanding that my evaluation should be firebox volume x HHV efficiency x ? - what do you mean by range of available outputs?

Thank you!

You don’t multiply these specifications, they are independent. Start with the epa list, it provides ba kground for each.

 

[cnapierala]

You don’t multiply these specifications, they are independent. Start with the epa list, it provides ba kground for each.

Sorry to be a newbie bit can you help me with where to go to do so? Is there a link online?

 

[begreen]

Here is the database. The advanced search option will narrow criteria. Note that the EPA testing can be with crib (soft) wood or hard wood and is with a fixed load of fuel, not the maximum capacity of the firebox. Besides the load size the draft is controlled so the test results are sort of like EPA car gas mileage results. The actual mileage may vary depending many factors like the speed driven, hills, temperature, acceleration rate, fuel quality, etc.

Woodstove Database | Burnwise | US EPA

 

[Highbeam]

You’ll need to know the manufacturer for that list. Like a Lopi is made by Travis.

 

[begreen]

You’ll need to know the manufacturer for that list. Like a Lopi is made by Travis.

Yes, sometimes the manufacturer is one or more levels up from the brand. One can sort on stove model to make this easier.

 

[cnapierala]

Thanks for all the tips. So i looked at each of these stoves and based on the EPA test the Lopi Liberty produces significantly more heat which is the opposite of what is advertised (See "Max Output (BTU/HR) per EPA") which is pretty confusing. Any insight on why this is the case? Do the non catalyst stoves typically put out more heat?

MFGR	Model	Max Log length	Heating space	Max Output (BTU/HR)	Max Output (BTU/HR) per EPA	Efficiency (HHV)	Firebox size (CU FT)	Flue Size	EPA Certified
Kuma	Wood Classic LE	18"	2400 - 3000	82000	30308	79.4 HHV	2.5	6"	Yes
Regency	F3500	20"	1500 - 2500	88000	36174	76 HHV	3	6"	Yes
Lopi	Endeavor II NexGen-Hybrid	19.5	2000	70,500	31922	80 hhv	2.5	6"	Yes
Lopi	NexGen Liberty	24"	2500	63239	63239	70 HHV	3.65	6"	No

Thanks everyone!

 

[Highbeam]

Thanks for all the tips. So i looked at each of these stoves and based on the EPA test the Lopi Liberty produces significantly more heat which is the opposite of what is advertised (See "Max Output (BTU/HR) per EPA") which is pretty confusing. Any insight on why this is the case? Do the non catalyst stoves typically put out more heat?

MFGR	Model	Max Log length	Heating space	Max Output (BTU/HR)	Max Output (BTU/HR) per EPA	Efficiency (HHV)	Firebox size (CU FT)	Flue Size	EPA Certified
Kuma	Wood Classic LE	18"	2400 - 3000	82000	30308	79.4 HHV	2.5	6"	Yes
Regency	F3500	20"	1500 - 2500	88000	36174	76 HHV	3	6"	Yes
Lopi	Endeavor II NexGen-Hybrid	19.5	2000	70,500	31922	80 hhv	2.5	6"	Yes
Lopi	NexGen Liberty	24"	2500	63239	63239	70 HHV	3.65	6"	No

Thanks everyone!

Because peak output is a bogus metric. Ignore your columns 4-6. Look at the range of available outputs. It's a range from low to high.

Peak output for a second is meaningless. It's the area under the curve that heats your home. Remember those calculus classes?

 

[Trevor Tahclep]

Very important items I personally would consider as important as EPA data, age of home/building and total square footage to be heated, insulation values, how well home is sealed and leaks, windows/doors square footage exposure ( heat loss and sun recuperation ), north south east west exposure for recuperating the sun's heat, region located, average winds, average temperatures in region 30°, 15° , - 0°, -10° etc., etc.

Ex.: windows normally have a far lower R value than 6 inch well insulated and sealed walls, the more glass square footage the more heat loss. The higher the winds in a given area the higher the heat loss, etc., etc. .

 

[begreen]

Of the stoves listed, the Liberty and the Regency F3500 will provide the highest sustained heat output when pressed for heat meaning more frequent reloads with high btu wood if available. Also to be considered in this size category would be the Osburn 3500.

 

[cnapierala]

Very important items I personally would consider as important as EPA data, age of home/building and total square footage to be heated, insulation values, how well home is sealed and leaks, windows/doors square footage exposure ( heat loss and sun recuperation ), north south east west exposure for recuperating the sun's heat, region located, average winds, average temperatures in region 30°, 15° , - 0°, -10° etc., etc.

Ex.: windows normally have a far lower R value than 6 inch well insulated and sealed walls, the more glass square footage the more heat loss. The higher the winds in a given area the higher the heat loss, etc., etc. .

Thanks for the message. Our house is 4500 sq ft. The stove will go in the main living area on the first story and there is an open 12-20' ceiling with a loft in the same airspace. I would estimate that the upper two levels are 2500 - 3000 sq ft if you consider the open ceiling. I think we will effectively be able to get the hot air into 2000 - 2500 of those sq ft without a bunch of fans etc.

We get a lot of solar gain when the sun is out in the afternoons and then the house cools off pretty fast when the sun goes down depending on the outside temps. We will likely be using the stove late September through May. We already have a heating source so this will be a luxury to be able to bring up the temp in the main area, save on gas and to dress up the room. We have lots of trees so wood will be free for us besides labor.

Climate data for our area: https://www.bestplaces.net/climate/city/colorado/divide

Basically, im looking for the biggest stove within reason (dont want it to take up the entire room with the hearth etc.).

 

[begreen]

A ceiling fan or two will be essential for circulating the hot air that will pool at top of the cathedral ceiling.

 

[cnapierala]

A ceiling fan or two will be essential for circulating the hot air that will pool at top of the cathedral ceiling.

Good news is we do have a ceiling fan in the space that moves pretty good air!

 

[Highbeam]

Thanks for the message. Our house is 4500 sq ft. The stove will go in the main living area on the first story and there is an open 12-20' ceiling with a loft in the same airspace. I would estimate that the upper two levels are 2500 - 3000 sq ft if you consider the open ceiling. I think we will effectively be able to get the hot air into 2000 - 2500 of those sq ft without a bunch of fans etc.

We get a lot of solar gain when the sun is out in the afternoons and then the house cools off pretty fast when the sun goes down depending on the outside temps. We will likely be using the stove late September through May. We already have a heating source so this will be a luxury to be able to bring up the temp in the main area, save on gas and to dress up the room. We have lots of trees so wood will be free for us besides labor.

Climate data for our area: https://www.bestplaces.net/climate/city/colorado/divide

Basically, im looking for the biggest stove within reason (dont want it to take up the entire room with the hearth etc.).

Giant heat load! You can't really go too big on the stove. Also, since you can never dream of heating the entire home with one stove, you will always need another heat source so you can't really go too small on the stove either.

Is your chart correct that the liberty does not have EPA approval? So is it even an option?

 

[mellow]

We have lots of trees so wood will be free for us besides labor.

Better start your woodpile now, they will be ready to burn in a year to a couple years once split and stacked depending on species.

 

[begreen]

Giant heat load! You can't really go too big on the stove. Also, since you can never dream of heating the entire home with one stove, you will always need another heat source so you can't really go too small on the stove either.

Is your chart correct that the liberty does not have EPA approval? So is it even an option?

I assumed that to be a typo. The Liberty is EPA NSPS 2020 compliant.

When I saw the volume desired to be heated I thought the same or a wood furnace.

 

[cnapierala]

Giant heat load! You can't really go too big on the stove. Also, since you can never dream of heating the entire home with one stove, you will always need another heat source so you can't really go too small on the stove either.

Is your chart correct that the liberty does not have EPA approval? So is it even an option?

It is not EPA approved for the energy tax rebate but we are still considering it as we really like the look of the stove, the quality of it and the dealer who sells it. I could to with their smaller model which is EPA approved for the tax rebate but it is smaller. Most likely the Liberty is going to come in $1000+ less than the Regency F3500 which makes up for the lack of tax rebate to some extent. Still waiting on some estimates.

 

[cnapierala]

I assumed that to be a typo. The Liberty is EPA NSPS 2020 compliant.

When I saw the volume desired to be heated I thought the same or a wood furnace.

That column is indicating if it qualifies for the 30% tax rebate.

 

[Trevor Tahclep]

'' Bestplaces Comfort Index​

The annual BestPlaces Comfort Index for Divide is 6.2 (10=best), which means it is less comfortable than most places in Colorado. '' + Very very LARGE home.

The larger the firebox the more wood in the box = MORE HEAT !

Go BIG, real BIG !