Moisture Content: CAT vs Non-CAT stove

[Kenster]

I asked this at the end of another thread but thought it might deserve its own post.

Is moisture content as critical in a non-Cat stove as in a Cat stove? Specifically, I have a VC Vigilant 1977. For the past couple of years since I got educated by becoming a disciple of the truth as preached by Hearth.com, I have tried to burn only dry ( < 20% MC ) wood. Now, with most of February, our coldest month) still in front of us I find myself running out of dry wood. I have almost two cords of water oak and pin oak stacked out back for the next year and two years out. Some of this wood is off the chart wet but other comes from broken off tree tops that were quite dead and drying before they ever hit the ground. Some of this stuff measures in the mid 20s Moisture content. Would it be a bad thing to burn some of this wood to get me through the next couple of weeks? I only burn when the overnight lows will be below 40 and we have three nights this week forecast in the 20s. I was hoping a little of that mid 20s MC wood might be used to supplement small amount of dry wood I have left.

What do you think?

 

[gyrfalcon]

I asked this at the end of another thread but thought it might deserve its own post.

Is moisture content as critical in a non-Cat stove as in a Cat stove? Specifically, I have a VC Vigilant 1977. For the past couple of years since I got educated by becoming a disciple of the truth as preached by Hearth.com, I have tried to burn only dry ( < 20% MC ) wood. Now, with most of February, our coldest month) still in front of us I find myself running out of dry wood. I have almost two cords of water oak and pin oak stacked out back for the next year and two years out. Some of this wood is off the chart wet but other comes from broken off tree tops that were quite dead and drying before they ever hit the ground. Some of this stuff measures in the mid 20s Moisture content. Would it be a bad thing to burn some of this wood to get me through the next couple of weeks? I only burn when the overnight lows will be below 40 and we have three nights this week forecast in the 20s. I was hoping a little of that mid 20s MC wood might be used to supplement small amount of dry wood I have left.

What do you think?

Absolutely you can do that. Less than perfectly seasoned wood will burn, though give you less heat, as long as it's got a good hot fire started underneath it with your dwindling stock of dry wood. (You'll also end up with a lot of charcoal, but that's a minor inconvenience compared to being cold.)

But - big but - only do it if your set-up generally produces very little creosote and/or you clean out your stack every few weeks.

I burned a lot of crap and made a lot of crappy low-temp fires my first year when I was learning the ropes, and the sweep only got a couple of cupfuls of creosote soot out of the chimney. But every set-up is different and some folks seem to accumulate a lot more creosote than I do, even when they're burning dry wood.

Couple of suggestions. If you don't have one, get a maul and split that less than perfect wood down as far as you have patience for. You'll use more of it that way, but it will burn hotter and better and safer. Another excellent option is to let that split-down wood sit next to your stove for a few days before burning it. As Battenkiller has proved through very careful experiments, wood dries ("seasons") rapidly that way.

I've got a couple piles of 2 and 3-inch splits of unready beech stacked near my stove, and they're quite dry and burnable after about 3 or 4 days. Bigger splits would take longer.

A better alternative would be to just burn until your dry runs out and then quit and go back to whatever your central heating is for the rest of the season and leave that unready wood where it is so it'll be really good to go next winter.

 

[gyrfalcon]

PS I'm a non-cat owner and have never run a cat stove, but I think maybe the cats themselves can get gunked up with less dry wood. As far as I know, they don't burn it any differently.

 

[ecocavalier02]

if the wood isnt as good leave the by pass open a little longer and let it get nice and hot. so you should do with a non cat as well. and check chimney more often.

 

[Kenster]

Thanks, guys. I brought in four or five nights worth of good dry wood tonight that I scrounged out of my own woods from tops that have fallen off for some reason, most likely storms. These trees are deep into my woods and not visible from my trails so I had to go "walkabout" to find them. Once they were cut and bucked I had to hand carry them through all sorts of scrub, thorny vines, etc back to my little tractor and wagon. After I cut one load up on site, I went to take my Stihl back to the wagon and got all turned around. Took me quite a while to get out of there and I eventually found the tractor/wagon but THEN I could not find the stash of wood I had just cut up.
Finally found it and got it all brought up to the house. To my pleasant surprised the fresh splits were showing around 15% on my Moisture meter. They are in the stove now and, from a cold start I was simmering water on the stove top in about ten minutes.

Gryfalcon, I gott a tell ya, the idea of turning on the heat pumps does not appeal to me at all. Fortunately, my Bride and I are both warm natured and having mid to upper 60s in the house during the day is fine with us. That's what sweaters are for.

There is more good solid, but very dry looking wood down back there in my woods. I think I'll get through this burning season okay. It shouldn't be more than a couple more weeks at most. I had the chimney cleaned at the beginning of this season. It had been many years since it was done. I was already planning on doing it again after the season, just to see how things are looking, now that I'm an edjicated burner. '-)

 

[Backwoods Savage]

if the wood isnt as good leave the by pass open a little longer and let it get nice and hot. so you should do with a non cat as well. and check chimney more often.

Right on Bobby. It takes longer to evaporate the moisture from green wood, so, you just wait for the moisture to leave the wood and then engage the cat. It still is not ideal for sure but it shows that the cat vs. non-cat is pretty much the same issue. Both still prefer dry wood.

 

[Kenster]

if the wood isnt as good leave the by pass open a little longer and let it get nice and hot. so you should do with a non cat as well. and check chimney more often.

Right on Bobby. It takes longer to evaporate the moisture from green wood, so, you just wait for the moisture to leave the wood and then engage the cat. It still is not ideal for sure but it shows that the cat vs. non-cat is pretty much the same issue. Both still prefer dry wood.

Again, this is a VC Vigilant, no CAT, hence the question. I'm understanding that a non-cat stove will handle wood with a little higher MC than a CAT stove. I'm not talking about fresh cut oak with a MC off the scale. I'm talking about a MC in the mid to upper 20s. Other than the possibility of increased creosote buildup it doesn't look like there is much of a problem. I really don't care if the window needs to be cleaned more often or not, so that is a non-issue.

 

[Wood Duck]

Well, a non-cat stove doesn't have a catalyst to foul up, so in that sense it is more tolerant of less-than-dry wood. You can gunk up the stove, window, and/or chimney with wet wood and fires that aren't hot enough, but the window can be cleaned, the flue should be cleaned anyway, and the stove itself will be cleaned out next time you make a nice, hot fire. No damage done, as long as you clean out the chimney.

Since it sounds like you have all oak, I'd split the stuff you want to burn this year pretty small. You'll need time to get big splits seasoned, but fortunately small oak splits still burn long compared to small splits of other, lighter wood.

 

[Kenster]

Over the past couple of days I went out into my woods and cut up two pin oak tops that had broken off in storms or had just fallen off due to the tree dying. Both tops, once bucked and split, measured around 15% MC. Today I went back to take down the main trunk of one of them. Got about 18 feet of six to eight inch trunk. Felt solid but not as heavy as green wood. Got it split and it ALL came in at 16-18%! Score! I think I have enough good wood now to get me through the season without dipping into the greener stacks for next year.