everburn to AFTERBURNER!

[Diabel]

So as I understand a flue damper will work the same way as a damper over the air intake. In that case it is easier for me to rig something up over the air intake since I have telescopic double wall pipe & apparently it is impossible to install your regular $7 damper from Home Depot.

Man I wonder if any of the old VC engineers visit this site sometimes....

 

[FireWalker]

Flue alarm? That's something I'd be interested in. Tell us more. Never heard of it.

I've seen a bunch of different designs. There are fancy expensive digital ones like this:
http://www.cas4.com/Wood-Stove/Woodstove-Control-001.htm

Or the "do-it-yourself" kind like this:
http://www.motherearthnews.com/Do-It-Yourself/1982-01-01/Mothers-Flue-Alarm.aspx
Which could be built for $15 using a cheap walmart smoke detector and a simple flue probe thermometer.

I've heard that people use these as well:
http://www.partshelf.com/maet73.html
But I'm not sure how good they can be if the range only goes up to the 400's. I guess you'd have to find some part of the stove that only gets to 400 in an overfire situation (and you would not have the faster warning you would get from an internal probe).

I understand a magnet looses it stick with high heat, sooooooo when it gets hot enough to fall off the connector pipe have it hit a bell on the way down. :cheese:

Edit: I amaze myself sometimes, not only did I just have a good idea, I told the whole world and thus ruined my chance at getting rich from it.

 

[Brian VT]

I have telescopic double wall pipe & apparently it is impossible to install your regular $7 damper from Home Depot.

I made it work. I cut the spring down to almost nothing and had to do some wiggling to get the bends of the shaft through but it's in and works.

 

[sullystull]

As some of you know, I have a DW large and experienced the thermonuclear event just recently. I contacted tradergordo and exchanged a series of emails basically covering the same information in this thread. Since then, I have taken a piece of foil and covered the rear intake--where you would mount the OAK. I cut a 1.5" hole in the middle to try and control the air intake. So far, it has not affected the performance of my stove during typical burns/weather. I do feel it has helped when we have strong winds and extremely cold temps. Currently, as I type this post, the outside temp is 25F and wind gusts of 25 mph and my everburn is purring along. These are the same conditions I had when I experienced my thermonuclear event. We often see 50+mph winds here in my neck of the woods and I am actually thinking of experimenting with a smaller diameter hole--to be able to handle the stronger winds and colder temps--before building a more permanent contraption. One thing I have realized is that it actually takes a bit (5-10 minutes) before my everburn kicks in. Meaning, when I engage, the rumble will start, then it will die off for a few minutes and then engage again after a few minutes. The reason I point this out is because once I noticed this pattern, it has helped prevent the thermonuclear event from happening. I can still close off my primary somewhat knowing that the everburn will eventually kick in after a few minutes. Whereas before, I would think it wasn't going to engage and I would open up the primary...causing the stove to come close to overfiring once it did engage. Just my two cents...

 

[trailblaze]

my everburn does the same... it will rumble for a few seconds at first, then die out, and if the draft is pulling hard it will soon start rumbling and pick up temp shortly afterwards...

i'll give the foil a shot... what can it hurt!

 

[Todd]

Just a thought and I am by no means an expert with these stoves but the more I read threads about this problem the more I think it's a design flaw. The secondary combustion chamber is located in the rear of the stove and it's going to get HOT. What does cast iron start to glow at? I heard 1400, well secondary combustion starts at 1100, so that doesn't leave much room. If this combustion was taking place in the front, top or middle wouldn't the heat disperse or dissipate some heat before exiting the stove? I think a pipe damper will only keep that heat trapped in the rear of the stove more? Maybe the draft needs to be increased to suck that excess heat out?

 

[trailblaze]

yeah, my father-in-law just left and said that cast will glow a dull red around 1200-1300 degrees... can't say for sure thats true, but he makes a lot of metal castings soo...

i didn't know secondaries started around 1100 degrees....

 

[Diabel]

Wow not a big margin! What did he say about cast glowing dull red?

 

[trailblaze]

well all he did was look at me after sayin the temp thing and .....in his own words said... "that's f'in hot"


i looked on wikipedia and cast supposedly melts at 1200 degrees Celsius or 2192 degrees Fahrenheit...

so if you hit 1500 degrees , your only 600-700 degrees away from the sides melting onto the hearth pad....

 

[sullystull]

Just a thought and I am by no means an expert with these stoves but the more I read threads about this problem the more I think it's a design flaw. The secondary combustion chamber is located in the rear of the stove and it's going to get HOT. What does cast iron start to glow at? I heard 1400, well secondary combustion starts at 1100, so that doesn't leave much room. If this combustion was taking place in the front, top or middle wouldn't the heat disperse or dissipate some heat before exiting the stove? I think a pipe damper will only keep that heat trapped in the rear of the stove more? Maybe the draft needs to be increased to suck that excess heat out?

I agree with you about the design flaw but I don't think more draft is what I need. I would love to hear what others think though.

 

[Brian VT]

When I've screwed up and got too hot I have opened the damper (to bypass the secondary) for a few seconds to dump some heat quick up the chimney before shutting the air down. The thermometers did show this helping a bit and it seemed to cool down a bit quicker than when I hadn't "dumped".
I have gottten scary hot a couple times (buried my thermometer once). Both times I turned the lights out to see if the cast iron was glowing anywhere. Nope.
There is some red "staining" in the side cavities but I don't know if that's from me or the previous owner.

 

[tradergordo]

Just a thought and I am by no means an expert with these stoves but the more I read threads about this problem the more I think it's a design flaw. The secondary combustion chamber is located in the rear of the stove and it's going to get HOT. What does cast iron start to glow at? I heard 1400, well secondary combustion starts at 1100, so that doesn't leave much room. If this combustion was taking place in the front, top or middle wouldn't the heat disperse or dissipate some heat before exiting the stove? I think a pipe damper will only keep that heat trapped in the rear of the stove more? Maybe the draft needs to be increased to suck that excess heat out?

I agree with you about the design flaw but I don't think more draft is what I need. I would love to hear what others think though.

First off, for anyone interested, the chart of temperatures and corresponding colors can be found here:
http://www.muggyweld.com/color.html
Blood red starts at 1200, ignore anything below that temp because those colors cannot be seen on a woodstove.

Blood Red 1200 F
Low Cherry Red 1375 F
Medium Cherry Red 1425 F
Full Cherry Red 1500 F
Bright Red 1550 F
Salmon 1650 F
Orange 1725 F
Lemon 1825 F

Second - its true that secondary combustion happens around 1100. The reason this combustion is isolated in the rear chambers, is because those parts of the stove are supposed to be heavily blanketed by refractory material, so there is no direct cast iron exposure. However most of have observed this refractory material deteriorating on our stoves after just 1 or 2 seasons, and the more it deteriorates, the more high heat exposure there will be to the cast iron.

"a pipe damper will only keep that heat trapped in the rear of the stove more? Maybe the draft needs to be increased to suck that excess heat out?"

This is totally wrong. It is the incoming AIR that regulates the burn. A damper (doesn't matter if its on the air intake, or on the flue) decreases air flow, which lowers the burnrate and therefore the temperature. More draft only makes things burn hotter, with increased air flow essentially creating a "blast furnace".

 

[Todd]

I don't think it's totally wrong Trader. If you think about it, there are times when a load is really gassing and if the secondary chamber is in the middle of doing it's thing and you decide to restrict the flow with a pipe damper it may flood the chamber with even more gas and smoke to burn, getting it even hotter. This may not last long, but what if its long enough to reach glowing temps?

The older stoves used pipe dampers to keep the heat from going up the chimney after you get a good hot fire going. I sometimes see this with my stove. I get her good and hot and turn it down too low too soon and the cat gets flooded with gas and smoke. The cat burns bright red, and the stove top temp will rise instead of falling. There are times when my cast iron baffle will glow a dull red. Maybe if the damper was just left in the same position throughout the whole burning process this wouldn't happen, but if you closed it off during a high gassing stage temps could rise temporarily?

 

[rtljr]

I'm a former VC Encore Everburn owner. My wife and I went through two Encores and both performed identically, i.e. uncontrollable burns and glowing cast iron around the flue collar.

Stove number one was installed in January 2007 and after break-in fires, would regularly run away. Our dealer adjusted the ash pan door and front doors; no improvement resulted. The dealer then was advised to check the bolts holding the refractory in place and he found the bolts were only "finger tight;" no improvement resulted. In June a Northeast Distributor representative visited our home and found issues with the ash pan door and front door fit and pronounced the problem resolved. Upon firing the stove in October 2007, I found that the same run away condition still existed.

At this point, I requested replacement with an Encore Catalytic, but Northeast Distributors said no and so our dealer installed Encore Everburn number two. Stove number two was installed in November 2007 and after the break-in fires we had our next run away. In addition, within a week, a crack developed in the shoe part of the refractory. A replacement shoe was ordered and we had a home visit from a VC field service representative based in Bethel, Vermont. Adjustments were made to the ash pan door and front doors and the stove was pronounced fit. After speaking to the VC rep the evening after he looked at the stove with our dealer (I could not be home for the visit due to my work), I fired the stove and it once again ran away. Each run away resulted in glowing cast iron around the flue collar and was accompanied by the "afterburner" sound.

The next step was installation of an in-line flue damper in January 2008. This had no impact on the stove's performance, i.e. it was still uncontrollable (although an oven mitt or aluminum foil stuffed in the secondary air intake would stop the "fun") and at this point I contacted the dealer once again. The VC rep called and said that we would then deal directly with the factory so as to take the burden off the dealer. He offered a replacement stove and in fact I could have chosen any of the VC or Dutchwest cat or non-cat stoves. Please remember that I had proposed replacement of stove number one with an Encore cat back in November 2007 and was told no deal. After thinking over the offer for a week, I called the VC rep back and requested removal of the stove and a full refund.

The real fun then began as neither the VC field rep nor the VC Northeast Regional Sales Manager would return my calls. In desperation, I returned to the dealer and explained the situation on a Friday in March 2008. The following Monday I received a phone call from a Northeast Distributor rep who informed me that he was going to be on the road with the VC Northeast Regional Sales Manager the following day. On Thursday, the dealer called to inform us that they would remove the stove and refund our money.

Unfortunately, the last time I spoke to our local dealer, they still had not been reimbursed for the two Encore Everburns that we had tried. I have nothing but praise for the local dealer, as they worked with us to try and resolve the issues. Northeast Distributors also finally did the right thing and authorized removal of Encore number two and refund. I hope that our local dealer was eventually made whole, but during the end game phase of this saga CFM declared bankruptcy.

The happy ending to this story was that after installation of Encore Everburn number two and experiencing the unending headaches and concern that I would burn my house down, I attended Woodstock Soapstone Stove Company's twenty-ninth anniversary open house. I came away duly impressed as a result of the conversations that I had with both production and support employees as well as management at Woodstock. Our local fire chief and his wife had also sung us the praises of their Woodstock Keystone. They had taken the stove to Woodstock for an inspection as it had been out of service for ten years. Their stove was one of the first Keystones built and the original builder (he was quite excited to see "his" stove come back) did a rebuild (one cracked stone was replaced the cast iron was bead blasted and repainted) and the stove was ready for service once again. I might add that the rebuild was gratis!

In April of this year, I took delivery of Keystone serial number 8000. What a phenomenal experience it has been! I've enjoyed total controllability, long burn times, and I've almost forgotten what a match and kindling look like due to this stove's ability to be stoked at 4AM and still have hot coals sufficient for a kindling free restart at 8PM. I'm especially thankful for my experience with the two Encore Everburns, as I would not fully appreciate how outstanding a product Woodstock makes without experiencing how inferior a product Vermont Castings makes in its Everburn line-up. I do understand that there are happy Everburn owners out there, but I'm convinced that the Everburn technology was optimized to produce good test lab results rather than user-friendly real-world results using cord wood. Besides, the flames in a Woodstock go up just as our creator intended, instead of being forced down as some VC combustion engineer intended!

Perhaps Vermont Castings' new owners will return it to the "glory" days of the original Defiants and Vigilants that I had great experiences with in the 1980s. I made the mistaken assumption that the VC name meant what it did back in the days of its original ownership and thus had my ill-fated experience with the Encore Everburn. I can assure readers that the Woodstock name still means what it did thirty years ago and it was a pleasure to attend this year's open house just as it was a pleasure to attend the VC Owner's Outings back in the 1970s and 1980s.

For those contemplating purchase of a stove using Everburn technology I can only say caveat emptor (let the buyer beware).

 

[Todd]

Too bad about your VC experience, but it sounds like you ended up with a great stove. I didn't know Woodstock did rebuilds? How much was that?

 

[tradergordo]

Yea, there have now been quite a lot of reports of these everburn overfires. It still amazes me that VC hasn't figured out yet that the problem is not always a leaky door gasket. At any rate, the one thing I still don't get from your story is why a flue damper did nothing to help but restricting the secondary air intake did? I guess that's one more reason not to go with the flue damper although I'd love to hear some ideas as to why it did nothing for you. As for the comments about stove designs, it took me a while to come around to it, but I agree, the burn tube on top design works great, its very simple and low maintenance and capable of long clean burns. No reason really to go with any other design at this point as far as I'm concerned. That said, I've gotten used to using my everburn stove and I'm getting good results so I'm pretty happy for now however I know those rear refractory chambers aren't going to last so I don't know what I'll do when its time to repair or replace.

 

[stanleyjohn]

I don't have a VC down draft stove but i do have a harman which has a similar design and haven't had any runaway fires so far or just lucky.I know someone at work who just got a VC stove and ill ask him how his is working so far.I don't really know how VC designed the ever burn stove but maybe they had one perfect set up they used to run their tests.Some seem to have good results with their stove while other just the opposite.Maybe the problem is that VC didnt test the ever burn with many different stove pipe heights and different climate conditions.I'm guessing that ones who have little or no problems have a set up very much like what VC used to test them and others with problems have nothing wrong which the stove!except that it isn't set up the way VC had it set up.It could be that VC never really properly test the ever burn system!know its flawed and keeping its mouth shut.

 

[trailblaze]

i used the foil on my secondary air inlet, it helped stop the meltdown that was starting yesterday.... that seems to take care of the problem...

however, today when i loaded the stove, i couldn't get it up to temp.... primary air control wide open.... and just a smoldering fire.... so i took the foil off and whooosh the fire picked up and all was well....

these stoves are finicky! it's working.... i'm warm this year so far... but in hindsight, i wish i would have bought the buck stove (second choice)

 

[stanleyjohn]

Dont really know how to do it but there must be a way to design alittle slide lever to put in place of the foil,which would give you easier options on your airflow.

 

[sullystull]

i used the foil on my secondary air inlet, it helped stop the meltdown that was starting yesterday.... that seems to take care of the problem...

however, today when i loaded the stove, i couldn't get it up to temp.... primary air control wide open.... and just a smoldering fire.... so i took the foil off and whooosh the fire picked up and all was well....

these stoves are finicky! it's working.... i'm warm this year so far... but in hindsight, i wish i would have bought the buck stove (second choice)

Did you block the intake completely with foil? Or, did you cut a smaller diameter hole in the foil and place it over the intake? Like I said, I have started with a 1.5" diameter hole on my set up.

 

[Diabel]

I did the same thing. Used aluminum duct tape & covered about 75% of the intake hole. Stuffed her full but she controlled herself ;-)

Now have to come up with a better adjustable apparatus....

 

[Ken45]

I'm not familiar with the particular stove, but would it be possible to increase the width of the control lever so that it almost entirely blocked the air opening?

Ken

 

[trailblaze]

i covered the whole hole with foil and poked my finger through it for air....

the darn foil kept falling off, so i need to figure out a better method...

ken.... the secondary air intake we are talking about is on the rear/ bottom, basically underneath the stove....there is no apparatus on it to close it, it's actually an outside air hookup... but something could be made to be attached and easily opened or closed depending on where you are in the burn

 

[Diabel]

i covered the whole hole with foil and poked my finger through it for air....

the darn foil kept falling off, so i need to figure out a better method...

ken.... the secondary air intake we are talking about is on the rear/ bottom, basically underneath the stove....there is no apparatus on it to close it, it's actually an outside air hookup... but something could be made to be attached and easily opened or closed depending on where you are in the burn

Blaze,

As mentioned in this post aluminum duct tape works very well

 

[trailblaze]

thats crazy.... i've never heard of aluminum duct tape....

that would take care of the falling off thing.... but i need something that can be adjustable and long lasting.... my fire just wouldn't start with that hole covered and one finger hole poked through for air....