Catalytic Combustor and Unseasoned Wood

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t0asty

New Member
Oct 12, 2021
16
NJ
Good Morning,

I currently have a VC Defiant 1975 that I am now pretty much set on upgrading to the "new" VC Defiant. This will be my first experience with a Cat stove and I read that unseasoned/green wood is not good for it as it will gum up. I have a ton of Ash wood that I split fairly thin 1-2mo ago and it has been covered and baking in the afternoon sun since. Normally, I wouldn't really give it a second thought and would burn it in my current old stove. However, with an expensive Cat in there will this do a lot of harm to it?
 

Rob_Red

Feeling the Heat
Feb 2, 2021
308
Southern New England
I went through a similar thing last season. New house, new stove, new wood.

New stoves don’t like to light up or burn efficiently with unseasoned wood. Luckily ash is already pretty dry.

For sure get a 20$ moisture meter from Amazon or a big box store and test your wood after freshly splitting it. From there burn the driest stuff you have.

Don’t engage the cat unless you have the fire ripping and it’s up to temp. You will probably get powdery fly ash plugging up the cat this will need to regularly be brushed off with a soft brush as you see the draft being choked down.

Use thin splits that can boil off moisture quickly even if you have to split your existing splits. Putting big chunks of unseasoned wood in there won’t do you any favors.
 
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t0asty

New Member
Oct 12, 2021
16
NJ
I went through a similar thing last season. New house, new stove, new wood.

New stoves don’t like to light up or burn efficiently with unseasoned wood. Luckily ash is already pretty dry.

For sure get a 20$ moisture meter from Amazon or a big box store and test your wood after freshly splitting it. From there burn the driest stuff you have.

Don’t engage the cat unless you have the fire ripping and it’s up to temp. You will probably get powdery fly ash plugging up the cat this will need to regularly be brushed off with a soft brush as you see the draft being choked down.

Use thin splits that can boil off moisture quickly even if you have to split your existing splits. Putting big chunks of unseasoned wood in there won’t do you any favors.
Rob, Thanks for the response. I usually have very hot fires, check my temps before closing the damper on my current stove. Since I split whatever wood I can find myself I always split it pretty thin so I have no issues getting it roaring and nice and hot. My current stove came with the house I bought about 11 years ago and I have had fires every winter since. Since the cat is something that is expensive and I personally don't have any hands on experience with I am concerned. However, the general consensus is make sure the fire is nice and hot, nice bed of coals, and the cat should be just fine (with the ash wood) before engaging. I will order one of those moisture meters today.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
26,102
central pa
Rob, Thanks for the response. I usually have very hot fires, check my temps before closing the damper on my current stove. Since I split whatever wood I can find myself I always split it pretty thin so I have no issues getting it roaring and nice and hot. My current stove came with the house I bought about 11 years ago and I have had fires every winter since. Since the cat is something that is expensive and I personally don't have any hands on experience with I am concerned. However, the general consensus is make sure the fire is nice and hot, nice bed of coals, and the cat should be just fine (with the ash wood) before engaging. I will order one of those moisture meters today.
I would suggest doing some research on the durability of VC stoves vs others on the market before committing to vc.

And yes any modern stove cat or not is going to need dry wood. Your old stove would have worked much better with dry wood as well btw
 

stoveliker

Minister of Fire
Nov 17, 2019
1,924
Long Island NY
Regardless of a cat, wet wood >20% will always be robbing you from much heat output - simply because you have to use much energy to boil (vaporize) the water in your wood. While older and/or non-cat stoves may be less finicky, why would you want to use a significant fraction of the heat your (hard worked for) wood to evaporate water...? (As you know from using a kitchen range, boiling water takes quite a bit of energy.)

Also, your flue stack may be cooler with a cat stove, possibly leading to condensation of water which will capture residual smoke compounds and create creosote.

Edit: hm, verbose repeat of what bholler said...
 

moresnow

Minister of Fire
Jan 13, 2015
1,842
Iowa
The 2 pin/prong type moisture meter has worked fine for me. Cheap. Have you considered getting your fuel supply issue straightened out prior to installing a new stove? 1 to 2 month seasoned split Ash is not confidence inspiring. Bring a selection of your splits up to room temp indoors(24hrs perhaps). Re-split these and test the newly exposed inner face/surface with your meter. Testing the outside or ends of the existing splits out in your pile without re-splitting means zero.
 
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t0asty

New Member
Oct 12, 2021
16
NJ
I would suggest doing some research on the durability of VC stoves vs others on the market before committing to vc.
I haven't seen any durable issues with VC stoves, but I'm assuming you know of some? I actually love my current Defiant 1975, I wish it had glass doors. The brick hearth where the stove is on the smaller side at about 32" deep and 46" wide which isn't up to code. But a VC stove will fit perfectly there as the more rectangular shape of VC.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
26,102
central pa
I haven't seen any durable issues with VC stoves, but I'm assuming you know of some? I actually love my current Defiant 1975, I wish it had glass doors. The brick hearth where the stove is on the smaller side at about 32" deep and 46" wide which isn't up to code. But a VC stove will fit perfectly there as the more rectangular shape of VC.
Old VC stoves like yours were fantastic and extremely durable. Newer stuff not so much