Burn time

[Bushels20]

How is burn time measured in the industry?

Last night I put a load of ash in at 8:30 p.m. this morning at 7:00, I easily reloaded from hot coals. Does that mean I had an 11 1/2 hour burn?
I have a 1.7 cu ft firebox that supposedly has a 7 hour burn time (on paper).

my insert is well insulated with a block off plate and I’m burning good wood but I’m thinking I am not beating the factory tested burn time by 3 1/2 hours.

Thoughts?

 

[firefighterjake]

Ah young grasshopper . . . that is THE question. The answer perhaps is whatever you want it to be . . . or more to the point it is whatever the spin masters deign the definition to be.

I always imagined it to be from first flame to when the flames went out . . . but after burning for awhile I wondered if it was from first flame to when there was no visible coals . . . and these days my own definition is from when there is meaningful heat coming from the stove to when the heat levels begin to drop off to the point where I need to reload the stove.

I suspect the manufacturers' definitions could vary as well.

 

[Jags]

I have dug out hot coals from the ash two days later...If you own a BK, that counts..
There is no golden rule. If you want to claim the time it heats your home before a reload, fine. You want to consider it the time the stovetop is above 300f (or any other random number) fine. For me - it is how well it is heating my home, since that’s its expected task. Some days its 4 hours, some days its 14.

 

[maple1]

I regard it as how much time passes, between loading it up, and the fire burning down to the level that I have to build a new fire. For which I need a reasonable amount of hot coals to avoid.

It is a pretty vague hokey measure.

 

[Bushels20]

I have dug out hot coals from the ash two days later...If you own a BK, that counts..
There is no golden rule. If you want to claim the time it heats your home before a reload, fine. You want to consider it the time the stovetop is above 300f (or any other random number) fine. For me - it is how well it is heating my home, since that’s its expected task. Some days its 4 hours, some days its 14.

Makes sense. I too get quite a degree of variance in the need to reload depending on the weather on any given day. Good way of looking at it.

 

[begreen]

Burntime like peak BTU output is a marketing term for the most part. A more valuable, and far less advertised specification is how long the stove produces meaningful heat. Or how long will it produce xx BTUs/Hr.?

FWIW, this is one of the oldest questions on Hearth.com. The new testing results coming out for the EPA 2020 stoves don't completely answer this question, but they do provide some more meaningful guidance.

 

[Highbeam]

The new testing results coming out for the EPA 2020 stoves don't completely answer this question, but they do provide some more meaningful guidance.

The new test results provide a possible range of btu per hour outputs from the stove and an efficiency. If you know how many btus of fuel you put into the firebox then you can get an idea of burn time at any of that particular stove's available burn rates. It's rough but at least you can compare apples to apples. A huge stove with a low output rate makes a long burn time. A small stove with a high output rate will have a short burn time.

When comparing burn times with other operators just be sure you know how they are measuring it. All methods are valid if they are well defined.

I believe burn rates, and therefor burn times, are a performance specification of the stove only. Repeatable in any home or out in the field. What burn rate you choose to heat your home is a function of the home, how leaky it is, the local environment, etc.

 

[bholler]

The new test results provide a possible range of btu per hour outputs from the stove and an efficiency. If you know how many btus of fuel you put into the firebox then you can get an idea of burn time at any of that particular stove's available burn rates. It's rough but at least you can compare apples to apples. A huge stove with a low output rate makes a long burn time. A small stove with a high output rate will have a short burn time.

When comparing burn times with other operators just be sure you know how they are measuring it. All methods are valid if they are well defined.

I believe burn rates, and therefor burn times, are a performance specification of the stove only. Repeatable in any home or out in the field. What burn rate you choose to heat your home is a function of the home, how leaky it is, the local environment, etc.

I agree with almost everything you said. But burn rates and burn times are not going to be the same across all installations because of variation in draft.

 

[Woodsplitter67]

I go by verry active coles with a stove top temp of between 250-275 degrees. Coles that i dont need to rake, just drop some splits on and off it goes on its own. I got like 16 hrs once a couple of years ago with a mix of oak and hickory..

 

[Merc1973]

My Quadrafire does not burn even close to that. I'm jealous. I'd say thats pretty good.

 

[maple1]

Our dinosaur at the cottage can go from full up load to ash in about 3 hours. But it looks kinda neat.

We don't use it enough to worry much about it, but if we did I would be putting a key damper in. I will anyway, if the pipe ever needs work. Would definitely get a different stove, if we need to get through a winter with it.