Back Puffing

[Ashful]

Wet wood.

I'm having troubles that I know are due to wet wood, and my MM is still showing 20% on freshly split faces at 20F outside. However, I have gotten to the point where I can feel by weight and apparent temperature, whether a split is too wet or not, and I definitely have several that are too wet.

If your cat is that slow to hit 1000F, and it's never getting up to more normal temps of 1300 - 1500 F, you are almost certainly burning wood that's a little to high in MC%.

 

[Woody Stover]

Sounds like you're on the right track, Stan, and I agree with Joful that as your wood gets drier, you'll get even higher cat temps and heat output. Keep on stackin'!

 

[Ashful]

Oh, I forgot to explain "apparent temperature," my own term, since I didn't know what else to call it. When I pick up a split from the stack on the porch, out in the cold with my bare hands, I can feel the ones that are too high in MC%. They feel colder, I think due to some moisture being pushed out to the surface and freezing. They actually feel icy. Extensive testing by me (6 loads per day thru two stoves) has shown that these icy feeling splits are almost always the ones too slow to take off, or to achieve proper cat temps.

Once I bring the splits indoors and they come up in temperature a few degrees, I can no longer tell the wet from the dry quite so easily, other than trying to guess by weight. Likewise, this method falls short in summer.

 

[Woody Stover]

my MM is still showing 20% on freshly split faces at 20F outside.

If I'm not mistaken, there is some variation in moisture readings with colder wood. Try testing a big one at 20*, then bring 'em up to room temp and re-test...

 

[Ashful]

I agree, which is why I was looking for a temperature compensation table for that meter, but I could find none. I will have to check some at room temp, the trouble there is getting a freshly split face in my living room.

 

[Charles1981]

I don't know why you would still be smelling smoke if the back puffing is truly gone. Maybe it is still back puffing but just not as visibly?

Or there is a leak in the stove/gaskets (but i wouldn't expect a smoke spill with that).

 

[mellow]

Some thoughts. It could be coming in via your damper rod? Take a look at that, last night while doing a reload with the damper wide open I noticed a bit of smoke come out of my damper rod hole on the front, wasn't much but I have never seen that happen before. Another thought would be to check the seals on your single wall pipe you have in the house, make sure you have no leaks.

Best thing to do is have a CO alarm nearby and keep an eye on it and see if you can track it down. Glad to see you got the additional pipe put up I truly believe that will help solve a lot of your issues.

 

[mellow]

Are there suppose be any flames in the firebox with the air all the way open?

Yes.

 

[oldspark]

I'm having troubles that I know are due to wet wood, and my MM is still showing 20% on freshly split faces at 20F outside. However, I have gotten to the point where I can feel by weight and apparent temperature, whether a split is too wet or not, and I definitely have several that are too wet

Well I will be outside a little later and I can play with some wood that I know is too wet to burn to see how my MM reads in the temps we have now, my MM has been right on the money so far with every thing I have tried it on but I want to see how these lower temps effect it.

 

[Ashful]

Have you pulled and inspected the cat recently? Every symptom you describe could be caused by a plugged cat. You should be able to see thru it.

 

[AppalachianStan]

plugged cat

Had the housing out Monday to clean the chimney and the cats look good.

 

[AppalachianStan]

The smoke is coming from the by pass rod.
Glass is cleaner then it has ever been.
Can a pipe leak cause it not to draft good?
Can my cats be too small at 2" x 2" x 16" for this wood stove?

 

[Woody Stover]

The smoke is coming from the by pass rod.
Glass is cleaner then it has ever been.
Can a pipe leak cause it not to draft good?
Can my cats be too small at 2" x 2" x 16" for this wood stove?

I can occasionally get a little smoke smell out of the bypass rod hole but the draft is usually good enough so that this doesn't happen.
Clean glass is probably an indicator that the added chimney length is helping.
I wouldn't think you are losing a lot of draft through the pipe joints but it seems your draft is low to begin with, so sealing the joints certainly can't hurt....

 

[Woody Stover]

I was looking for a temperature compensation table for that meter

Someone said they were gettting 4% lower when cold....

 

[raybonz]

The smoke is coming from the by pass rod.
Glass is cleaner then it has ever been.
Can a pipe leak cause it not to draft good?
Can my cats be too small at 2" x 2" x 16" for this wood stove?

If your wood moisture content is suspect you can rule that by using a few of these as a test Stan.. These are very dry so only burn maybe 3 at a time..

http://www.tractorsupply.com/en/store/redstonetrade;-ecobrick-pack-of-6?cm_vc=-10005

Ray

 

[AppalachianStan]

Raybonz, I have tried them and had wife pick up some today.
The stove started back puff last night again. This is getting old
May wood is between 19 and 15% so I don't thank its the wood. Tried to get some kiln dried it was at 25%.
I am going to try the eco blocks to see if that helps.

 

[raybonz]

Raybonz, I have tried them and had wife pick up some today.
The stove started back puff last night again. This is getting old
May wood is between 19 and 15% so I don't thank its the wood. Tried to get some kiln dried it was at 25%.
I am going to try the eco blocks to see if that helps.

That sucks Stan.. My old catalytic DW was prone to backpuffs but your stove seems much worse than the CDW.. I would not want to deal with this either.. New stove doesn't backpuff at all.. Very easy to use and no aggravation.. Good luck Stan..

 

[AppalachianStan]

If I run double wall stovepipe would I get more draft?

 

[raybonz]

If I run double wall stove would I get more draft?

(broken link removed to http://www.northlineexpress.com/fireplace-hearth/fireplace-accessories/smoking-fireplace/draft-inducers.html)

This might help especially if you get decent air movement where you live..

Ray

 

[AppalachianStan]

Ray, maybe it time to start looking for a newer wood stove.

 

[raybonz]

Ray, maybe it time to start looking for a newer wood stove.

Yup I agree! I am glad I did it! One lever controls everything on this stove. Very easy to learn..

 

[Woody Stover]

If I run double wall stovepipe would I get more draft?

I'm not sure, but I think adding the 3' of chimney would increase the draft quite a bit more than you could expect from double-wall.

Ray, maybe it time to start looking for a newer wood stove.

As Ray said, some stoves are more prone to backpuff. You've pretty much addressed everything else. You've got an 8" chimney, so a stove that's 8" would be ideal. Might be able to get an easy-breathing 6" stove to work....I'm not sure how much draft you would lose.

 

[tcassavaugh]

hope the pipe helps. just wondering, you said in you first post that it happens when the load is almost burned up......have you tried opening the draft just a little more at the end of the cycle (sorry if I missed that). sounds like that's the easiest, especially if you know its going to happen. I have occasional problems with back puffing buts that's when I don't give the fire enough air to keep going but mine are more at the beginning if I shut it down too soon. I had a ductchewest cat stove that was notorious for back puffing unless you were running it pretty hot, and it was a primary influence to go back to non-cat stoves.....like I said earlier, I still get an occasional back puff but its because I try to shut it down too soon.

 

[oldspark]

I'm not sure, but I think adding the 3' of chimney would increase the draft quite a bit more than you could expect from double-wall

Yea for sure.

 

[raybonz]

Stan if your draft is marginal I think you'd be better off with either hybrid stove (cat + secondary burn) or just secondary burn because you get hotter stack temps with secondary burns which would heat your flue and enhance the draft.. Just my 2 cents.. I have never seen a backpuff with the T-5 and got that sometimes with the CDW especially in milder or damp weather.

Ray