What Kind of Burn Time Should I Expect?

Q: Hi
I have a Hearthstone Homestead wood stove. I am checking with you for some info on burn time. At first I was crying about heat but we resolved that problem. I think it was a time thing: after the camp got warmed up which took about four hours heat was not a problem.

Now I'm looking at burn time. How do you figure what burn time is? My best time on low air is about 4.5 hours. The wood is burned up, but there are still embers which I can start a new fire with. When I check my temperature gauge on top of the stove it reads about 280- 320 degrees. Am I getting too much air? If not, what is the next step?

Thank you
Dale G

Hi Dale
We define burn time as the time that elapses between a freshly started fire and the point where there are just enough coals left to kindle the next load (aka match-free burning).

Once you've established that your door and ash cleanout gaskets are making a good seal, the "holy trinity" of variables that affect burn time are draft control setting, size of load, and quality of fuel.

Draft Control Setting: Your longest burn time will be at the lowest draft control setting. If you need to open the draft because the lowest setting doesn't produce enough heat, your burn time will be shortened proportionately.

Size of Load: Your stove will burn X pounds of fuelwood per hour at Y draft control setting. At any given draft control setting, bigger loads will burn longer.

Quality of Fuel: If you burn a full load of well-seasoned Hedge in a Homestead and adjust the draft control to its lowest setting, you can expect to find hot coals up to ten hours later. As you move down our firewood btu chart, your burn time will get progressively shorter until you get to White Cedar, which might burn down to refuel stage in an hour or so! Any moisture content in the wood greater than 20% will shorten the burn time. Burn time also goes down progressively as the wood gets TOO dry (less than 10% moisture content). The worst example of this is kiln-dried lumber, which, regardless of species, will burn up even faster than White Cedar.

The wild card factor in the equation is excessive chimney updraft: no matter how tightly you compress door gasketing, air can be drawn through it when enough force is applied. If, even when you turn your draft control down all the way, your house is too hot and your fuelwood is burning up too quickly, you might consider a stovepipe damper.

Our take: your 280-320 stovetop temperature doesn't indicate excessive chimney updraft: soapstone stoves often stay that hot for hours after the fire dies down. We would suggest you take a hard look at the quality of your fuel. A 4.5 hour burn would be about what we'd expect to see from your 2 cu.ft. firebox if you're burning well-seasoned fuelwood from the orange section of the chart.