VC encore back puffing

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Krabecal

New Member
Feb 6, 2023
5
New York
This is long I'm sorry lol I have a VC encore with the cat and I'm at my wits end. I've never really had luck with this thing running smoothly I can never get a burn longer than 6 hours and that's with it choked all the way down and then I'm scraping the glass clean. It advertises 12 hour burns. I've also found it's very inconsistent in its temperature. I can have the air down and we're cruising at 450/500 and then all of a sudden it skyrockets. I was just watching videos and apparently it's supposed to have a thermostatic thermometer on a coil? This certainly doesn't operate like that lol Recently I've been having trouble with back puffing. I load the stove, let it get to 450 as per the manual, then engage the cat by closing the damper. Unless the thermostat is open completely the fire has been getting snuffed out and I get the back puffing. If I leave it all the way open it runs away on me and we're over 700 in a matter of minutes. My wood isn't the best it's prob like 18%-22% from what I've tested idk if that's contributing to it. I just had it swept cause I thought maybe I had too much creosote or there was a blockage and while it was dirty nothing was blocked. I try to shut it down slowly but the second I touch that air control now it starts back puffing. I don't feel comfortable running it when I'm not home now.

So run on full blast and over fire or close it down and back puff seem to be my only options

video of the back puffing. Its starved for air but if I open it up it gets too hot
 
I have found that wet wood can cause temperature fluctuations like that. The water vapor kills off the fire when the air supply is dialed back, then the coals or remaining fire cooks the wood for a while until it finally ignites and either puffs or ramps up quickly.

How are you testing your wood? You said it is "probably" 18-22% which kind of implies you didn't test it or you are not confident in your test method.

If you don't want to buy a moisture meter right now or are not confident in the one you have, you can get some bio bricks (pressed sawdust logs) from a Tractor Supply or similar store and try those. That will answer the question as to whether it is wet wood.

A moister meter is only $20-$30. It is not a bad idea to have one.
 
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I have found that wet wood can cause temperature fluctuations like that. The water vapor kills off the fire when the air supply is dialed back, then the coals or remaining fire cooks the wood for a while until it finally ignites and either puffs or ramps up quickly.

How are you testing your wood? You said it is "probably" 18-22% which kind of implies you didn't test it or you are not confident in your test method.

If you don't want to buy a moisture meter right now or are not confident in the one you have, you can get some bio bricks (pressed sawdust logs) from a Tractor Supply or similar store and try those. That will answer the question as to whether it is wet wood.

A moister meter is only $20-$30. It is not a bad idea to have one.
I have a moisture meter but I've only tested a handful of pieces. I finished all my well seasoned and the rest of my stuff wasn't ready so I just had two cords delivered and tested a bit and it varied from 18-22 but it's a small sample based on the size of the delivery
 
Do you do top down starts? If I had to burn marginal wood I would opt for them as they would heat up the flue quick and help get a good burn established (I feel they do a good job getting residual moisture out of wood). Also, if your winter has been like mine since we are both in Wisconsin things are abnormally warm which would likely mean less draft and a better chance of back puff. Short, hot, smaller top down fires may be the way to go with your marginal wood.
 
How exactly are you testing the wood.. are you putting the moisture meter in the end or the side or are you splitting it open and checking on the freshly split face..

I actually have an encore and it runs great. How are you dialing your air back.. are you going from full air open to all the way closed.. mid way.. expand on this..

What are your catalyst temperatures when this happens and what is flue temperature.

What is the height of your stovepipe is it 6 inch .. is it straight up.. give some detail on this
 
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I have an older Encore, backpuffing happens but yours is impressive. You're talking about 500 and 700 temperatures, where are these measured and how? I don't close my air down until I see 1000 at the cat measured with a thermocouple probe displayed on an Auber meter. From a cold stove I wait until STT is 500+ before flipping the damper and engaging the cat.
Backpuff happens to me on occasion when I cut the air down and the box goes dark instead of having hose dancing flames. If it's warmer out it will do it easier. The box has a lot of potential and sucks air in and it flashes over causing the puff. Mine only comes from the top load but I don't have anything on my griddle.
 
I have an older Encore, backpuffing happens but yours is impressive. You're talking about 500 and 700 temperatures, where are these measured and how? I don't close my air down until I see 1000 at the cat measured with a thermocouple probe displayed on an Auber meter. From a cold stove I wait until STT is 500+ before flipping the damper and engaging the cat.
Backpuff happens to me on occasion when I cut the air down and the box goes dark instead of having hose dancing flames. If it's warmer out it will do it easier. The box has a lot of potential and sucks air in and it flashes over causing the puff. Mine only comes from the top load but I don't have anything on my griddle.

Dude.. dont you love it when people abandon their own threads.
 
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