Define Burn Time

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mhrischuk

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From match to cold coals?

From first productive heat to last productive heat?

A time of temperature not going below a certain point? In other words... 300 deg stove top at the start to 300 deg stove top at the end.

It seems it would be difficult to compare burn times without a standard method.
 
I have always been told its from the time you set your air control till you can rekindle a fire without a match. Its tricky though because most think of it as useable heat time. It truly isnt that way from the manufactures though.
 
mhrischuk said:
From match to cold coals?

From first productive heat to last productive heat?

A time of temperature not going below a certain point? In other words... 300 deg stove top at the start to 300 deg stove top at the end.

It seems it would be difficult to compare burn times without a standard method.


That is how I define it and that is how I ask for burn time estimates from others on here when I am researching a stove. This is not how stove manufacturers measure burn times, though.

For instance, the Heritage will produce a 5-6 hour burn times using this method. The manufacturer claims 8 hours.
 
Burn time? The morning after supper at the Thai restaurant.
 
JimboM said:
Burn time? The morning after supper at the Thai restaurant.

 
mhrischuk said:
From first productive heat to last productive heat?

Thats how I look at it...

Shawn
 
My local dealer, when discussing my future Jotul f600 purchase said that runtimes by the manufacturers were lighting the kindling to the last coals dying.

Not sure if it's true but he was giving me an honest number on what the runtime would actually be in the giving of heat. I was told to take off about two hours from the posted run time to get a better number of productive heat.
 
Burn time: The length of time that my stove heats my house.

If its 45F outside, it could be 12-16 hrs.
If its 10 below with the wind blowing, it could be 4-5 hrs.
If it ain't heating my home - its not productive. Just one dudes opinion.

I do believe that MFGs should have a standard, whatever that be, so there can be a real world comparison between stoves.
 
If you're on the west coast and burning pine your burn time is a lot different to a guy that has access to oak.

There are no standardized method to define 'burn time'. It's up to the marketing dept to define it. It's unfortunate because I have seen people buying a wood stove because the lit stated a longer burn time than another stove of the same cu. ft.

Our company defines 'burn time' from the time the secondaries kick in to the point there are enough coal to re-ignite a stick.
 
Jags said:
Burn time: The length of time that my stove heats my house.

If its 45F outside, it could be 12-16 hrs.
If its 10 below with the wind blowing, it could be 4-5 hrs.
If it ain't heating my home - its not productive. Just one dudes opinion.

I do believe that MFGs should have a standard, whatever that be, so there can be a real world comparison between stoves.

+1... I agree. If it aint heating my home....its not burning. I had a fire in my insert the other night. Put the last wood on around midnight - blower was still blowing and there were still enough coals in the stove for a re-light 18 hours later, at 6 P.M. Did I have an 18 hour burn?.......I dont think so.
 
Seems to be a monthly question during heating season. There really is no definitive answer, especially after the marketing dept. gets involved. There are lots of threads covering this. I've provided some below. For more, just search on Burn Time. Most often we refer to the period of meaningful heat as the most informative, however you want to define it. 250F or 300F are both fine temps to use. A big rock like the Equinox is going to still be radiating a lot of gentle heat when it is 250F.

Here's some informative discussions on the topic:
https://www.hearth.com/econtent/index.php/forums/viewthread/68849/
https://www.hearth.com/econtent/index.php/forums/viewthread/53902/
https://www.hearth.com/econtent/index.php/forums/viewthread/45249
https://www.hearth.com/econtent/index.php/forums/viewthread/29085/
https://www.hearth.com/econtent/index.php/forums/viewthread/16296/
 
I consider it to be how long I can go from loading the stove until I have enough coals to load it up without having to use a match or kindling to get it going. I get about 6-7 hours of useable heat from my stove but I can go about 8-9 hours without having to start over. Burn time to me is really only important overnight and when I am at work and I really just want to be able to add some small splits and get the fire going each morning and after work, I don't mind that the temp starts dropping a bit after 6 hours, I just don't Don't want to have to build a new fire each morning and evening.
 
I think that is often the measurement used by the stove mfgs. too krex. As you point out, that measurement has its value too. I love a longer burn time because I go to bed around 11pm and don't want to have to get up to refill the stove at 0-dark-thirty in the morning. With softwood, this is a challenge in a smaller stove.
 
For me burn time is the time when I get usable heat from my stove to the time when there are still enough coals to keep the stove pumping out heat . . . or at least there are enough coals to easily ignite a reload . . . which in reality means two different figures.
 
From the time I reload to the time I have enough coals for another load to take off without kindling. Usually I have enough coals for this with a stove top around 200. This little stove has gone 12+ hours between loads but colder weather cuts burn times down some.
 
I don't know how it is defined, but I know how I'd like it to be defined:


The longest time it takes for the maximum load (in pounds) to burn down to an industry-standardized percentage of remaining fuel (say, about 10% by weight).

For example, if your stove is rated to take 60 pounds of wood that is 20% water by weight, maximum burn time would be the longest time it would take to get down to 6 pounds of fuel remaining... or about a decent sized coal bed.
 
Battenkiller said:
I don't know how it is defined, but I know how I'd like it to be defined:


The longest time it takes for the maximum load (in pounds) to burn down to an industry-standardized percentage of remaining fuel (say, about 10% by weight).

For example, if your stove is rated to take 60 pounds of wood that is 20% water by weight, maximum burn time would be the longest time it would take to get down to 6 pounds of fuel remaining... or about a decent sized coal bed.

Now that is a standard I could learn to live with. You could even augment it by requiring a minimum temp.
 
Jags said:
Battenkiller said:
I don't know how it is defined, but I know how I'd like it to be defined:


The longest time it takes for the maximum load (in pounds) to burn down to an industry-standardized percentage of remaining fuel (say, about 10% by weight).

For example, if your stove is rated to take 60 pounds of wood that is 20% water by weight, maximum burn time would be the longest time it would take to get down to 6 pounds of fuel remaining... or about a decent sized coal bed.

Now that is a standard I could learn to live with. You could even augment it by requiring a minimum temp.

Yeah, and they have every blasted one of these things sitting up on a scale during the entire EPA test, so it wouldn't exactly be hard to accomplish, either.
 
I never pay any attention to it. When the stove needs fuel, I give it fuel...without a thought to how long it's been since I last gave it fuel. Rick
 
BeGreen said:
Seems to be a monthly question during heating season. There really is no definitive answer, especially after the marketing dept. gets involved. There are lots of threads covering this. I've provided some below. For more, just search on Burn Time. Most often we refer to the period of meaningful heat as the most informative, however you want to define it. 250F or 300F are both fine temps to use. A big rock like the Equinox is going to still be radiating a lot of gentle heat when it is 250F.

Here's some informative discussions on the topic:
https://www.hearth.com/econtent/index.php/forums/viewthread/68849/
https://www.hearth.com/econtent/index.php/forums/viewthread/53902/
https://www.hearth.com/econtent/index.php/forums/viewthread/45249
https://www.hearth.com/econtent/index.php/forums/viewthread/29085/
https://www.hearth.com/econtent/index.php/forums/viewthread/16296/
Those links are great and all, but none of them have my opinions in them. Aside from Proposed EPA definitions, I believe I came up with the correct definition of burn times last season as to be measured by forum members. A search will get you there, I bet.

Please return to your discussion,
Danno77 , PhD. In making stuff catch fire, Forum President, and Licenced Clinical Practitioner of Writting nonsense on the Internet.
 
burn time = in winter, that amount of time from when you've loaded your stove up until you find yourself loading it again to keep your arse warm.
 
Todd said:
From the time I reload to the time I have enough coals for another load to take off without kindling. .
There it is. Burn time is just that. Burning can be considered flames burning or coals burning. The OP stated "burn" time, not heat time right? A thicker metal construction can and will retain radiant heat longer but that doesnt mean the fire is still burning.
 
Loco Gringo said:
Todd said:
From the time I reload to the time I have enough coals for another load to take off without kindling. .
There it is. Burn time is just that. Burning can be considered flames burning or coals burning. The OP stated "burn" time, not heat time right? A thicker metal construction can and will retain radiant heat longer but that doesnt mean the fire is still burning.
That's not a great definition, because I've been able to rake away some ash and find some glowing coals about 24 hours after my last loading, throw some dry wood on it and 15 minutes later there's a fire a roarin'.
 
I'd certainly hope so. When it's not not too cold out I put wood in teh stove once per day... I'm not lighting fires.
 
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