Are short burns bad for stove/flue?

[GlasgowDrift]

First up, confession time, we have gas central heating and while the wood burner adds to the overall temp over winter but it isn't our main/only heat source.

So with this in mind, can you help me settle a minor arguement? My wife claims that once the stove is up to optimum temp that it's better to keep chucking logs on for the next 6 hours+. I jokingly call her "one more log Potter" but in all seriousness that is fuel (aka money) being burned. We won't freeze.

If you take the hassle of getting the stove lit and up to temp out of the equation (I've got this down to 5 mins building and 10 mins warming up) is there actually anything bad about using the woodburning stove for a short 2hr fire? Or put another way, is there a minimum duration that it should be run for?

I've searched the forum for "duration" "minimum time" etc... And couldn't see anything that answered this question directly.

 

[barnaclebob]

It would be hard to determine what the best option is. 10,000 hours of 10 hour burns will certainly have less wear than 10,000 hours of 2 hours burns. But if you are burning your stove more than you would be otherwise just to keep the heat/cool cycles longer then you might be cancelling out any benefits.

 

[begreen]

Short burns are not necessarily bad, the bigger concern would be a smoldering fire. If the flue gases are consistently below 250ºF then they will condense. My wife never does a full reload. She is more comfortable with putting on 2-3 splits on the coals, so I have her watch the flue thermometer to make sure it stays hot enough during the wood outgassing phase.

 

[Ctwoodtick]

You’ll get some more soot over time with more frequent startups. It’s nothing that checking/sweeping the flue system a bit more often can’t address.

 

[Ludlow]

Just admit that you dont feel like cutting and splitting more wood. Once you do that the healing can begin.

She is probably right though. Heat up and cool down cycles cause expansion and contraction. The less times it happens the better. Just like freeze-thaw damage to roads, buildings etc.

 

[bcrtops]

Like @begreen has said.................
We do a lot of short burns & small fires during shoulder season & cool summer days. Oftentimes difficult to keep a "clean" burn going, which will result in a dirty window & soot(ed) up firebox & chimney.

 

[begreen]

I did a short fire this morning. We have a bunch of dry splitter scraps that I want to burn up. I started a fire with a teepee of them, then added another handful once the fire was burning well. That was enough in our big stove to get the flue up to 450º and for secondary combustion to start. I added one more batch as the first loading burnt down. The flue temp did not go below 400º. All of this was with a no more than 1/4 full firebox and 55º outside temp. The fire got up to temp quickly because the pieces of wood were only 1-3" across. I could have put on a couple 4" splits at that point if I wanted the fire to continue cleanly but the sun came out and is warming up the house so I am letting the fire go out.

 

[SpaceBus]

I did a short fire this morning. We have a bunch of dry splitter scraps that I want to burn up. I started a fire with a teepee of them, then added another handful once the fire was burning well. That was enough in our big stove to get the flue up to 450º and for secondary combustion to start. I added one more batch as the first loading burnt down. The flue temp did not go below 400º. All of this was with a no more than 1/4 full firebox and 55º outside temp. The fire got up to temp quickly because the pieces of wood were only 1-3" across. I could have put on a couple 4" splits at that point if I wanted the fire to continue cleanly but the sun came out and is warming up the house so I am letting the fire go out.

This is a great load plan. I do basically the same thing, having read about it here, and it's great.

 

[begreen]

It didn't take too long to come up to temp either. I started turning down the air after 10-15 minutes. Not all the way down, maybe about 60%, just enough to slow down the fire but still let it burn well.