Vermont Castings Encore 2550 - Refractory Assembly Question (w Pictures)

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oldAGE said:
.... worked perfectly well with this stove up until Christmas Day, 2007.

Sheesh, it's all perfectly clear now! Have you checked for a Santa stuck in the flue? :)

Perhaps, as others suggested, there's an air leak. On my Intrepid, there's a spot near the back right corner where the tie rod goes through the firebox floor .... the furnace cement tends to fall out. You can then see daylight out through the primary air vent from inside the firebox. Perhaps a similar situation exists on your stove that's allowing uncontrolled air into the firebox? Recheck your assumptions about which seals/gaskets are good....check 'em all again.
Good luck.
 
Oh, don't get me wrong, I truly believe there is an air leak. I never doubted that one exists. I just can't find it. I have gutted the box... On the Encore you can remove the lower fireback, upper fireback, and the inside wear plates (left and right). I dug and scraped any loose cement, wire brushed the areas, and tried to reseal the best I could with furnace cement. I used a halogen work lamp in a dark room and can see no "daylight" whatsoever.

Regarding the gaskets -- they all passed the dollar bill tests after I installed them. I will test again but everything feels firm when latched down.

Results of last night's fire (using a new Mastercool Infrared Thermometer) -- normal start up, normal load up, primary air closed down to 1/4, two large splits took the stove from 400 to 650, closed primary air and the stove cooled to 500 and no lower, decent coal bed, filled the box 2/3 full, opened primary air to 1/4, she sat around 550 for a good while and then when she reached critical mass, she rose to 700+ and stayed there for a good long time.

So, yes, I believe air is coming from somewhere but I just don't know where. I am at a loss but will check all the gaskets again.

AGE
 
Wow - what a challenge to get full functioning out of a unit that had been performing fine. Thanks for taking us through it, Really Hot. I just bought a second hand Encore today - assuming I'd have to replace the cat, but upon inspection, it looks like I am going to have to replace the refractory materials too. Ouch - otherwise the stove is in great condition, and fortunately, not just according to me and the seller! This thread has been a very useful discussion of that replacement situation, and the uncertainty of the outcome even if all reasonable steps are taken. So to the question - did you ever get closer to the performance you'd hoped to reach after all your steps, maybe after a "break-in" period? Also, in my particular case, is replacing the refractory assembly a difficult job in and of itself? It sounds pretty doable from what I have read, but a step by step for the VC neophyte would be gratefully accepted. Thanks!
 
You can't have overfiring without excess air. Have you done a full check for leakage? the ash door is the obvious suspect, as it requires regular regasketing, but the window seals can start leaking as well.

Oh, the drywall screws were probably just to hold the assembly together until the refractory cement dried. A very common practice.
 
Hey there fellow VC encore 2550 stalwarts. thank you all for contributing your experience and expertise to this forum. I have a bit of expereince now, but no expertise yet, with operating my particular VC 2550. To do so, I went through the process of replacing the refractory and the gaskets myself, and then with help, installing the stove into a big hearth with a 25 foot 8" liner newly installed. I think I did a pretty conscious and decent job on my side of this effort, having learned from you folks how touchy this stuff can get, but I don't claim perfection.

The first couple of time we used the stove, it seemed somewhat more controllable heatwise than it does now. much as others have described their experiences. Once a good bed of coals has been established, and the heat rises to approx 450/500, we engage the cat and basically shut down the damper. At the point, with only two or three logs in it, it will go up to 600+ for a quite awhile, generating good heat and not burning much wood. The smoke outside is all but invisible, so the cat's doing it's trick (no noise to speak of inside, perhaps the quitest rumble). If we want more heat, we open the damper a bit, something we do when the fire backs off to 500 - 550. At that point though, if we add another log or two, and want to keep the fire burning in our "medium" comfort zone, it seems to want to take off and run up to and even over 700, to 720, or once, 750, even with the damper fully closed.

This makes us anxious.

Then, when the stove has settled down a bit, it seems to, again, with damper closed, want to run at about 700 steadily. We feed it along with a log or two, keeping it dampered, and maintain usually between 600-700 through the day.

So here's (finally) my questions:

1) My understanding is that the stove should be happy around 700, even for long burns, and at a bit more than that even for short periods, so I shouldn't have to worry that I am doing anything "wrong" by using it as it runs right now. Is this correct? The manual and some portion of the postings here seem to support that assessment, but I'd feel better confirming it.

2) What about longer burns, overnight, for example, when I want to load up the fire and damper it down with a lot wood, I don't want to worry that it's going to run away on me. Can I do this safely under the current circumstances? I have read that burning more wood, some if it less than dried, can bring down the temp of the burn, and I am burning pretty dry wood right now by my estimate. If I add a little less dried wood to mix and start with a hot, but not too hot fire, then damper it, should I be able to burn a bigger load? We haven't tried this 'cause we're chicken, I mean cautious.

The house is a 1783 colonial with probably about the same square footage, but without fantastic insulation, so having the stove fire away at the level it's been firing actually does a very nice job of heating our place, so I don't actually object to burning at around 700 so long as it's not a hazard to us, the house, the stove in that order. When it gets colder, I will be even happier with the heat output, and I am otherwise very pleased with the unit in terms of how much you get out of a chunk of wood. Kinda amazing, actually.

Oh yeah, and if it is running too hot, what are recommended steps for bringing it back down while the fire is underway. I want to know just what to do when it's trying to push much past 700?

So finally, thanks again for the expertise to date, and any feedback you might have on this Encore's encore in this case, and safe wood heating to you all.


Nick G. in CT
 
oldAGE said:
Hello folks -

Today I removed my upper fireback from my VC 2550 CAT stove. Many know that I have been fighting an over fire situation where my stove with Primary Air closed will burn two splits and hit upwards of 700 degrees. Engaging the CAT (brand new Condar) I would not get the classic rumble. In short, the stove has not been behaving as it has since Christmas. I have had this for 7 years (installed new) and have learned its traits to the letter.

In my quest for looking for leaks, bad joints, etc, today I removed the upper fireback. Enclosed are pictures of my refractory assembly (CAT removed). Please tell me your opinions upon reviewing the photos. Thanks again to those who have been providing me outstanding assistance regarding this issue.

AGE
Hello,
How did you remove the upper fireback? Is it cemented in? Does anyone have some directions on how to replace the refractory assembly? I have the lower fireback out. That was just two pins that hold that in, but the upper one looks like it is going to be trouble. I have only burned two seasons with my Encore that was purchased in fall of 2008, but I poked a hole in it when trying to clean off ash and stuff off of the top of it. I am going to save the old one in case Io need some of the material to fix my new one if possible. Any help or suggestions are appreciated.
Crispy
 
Crispy -
That is truly a bummer. Is your stove a newer model than the 2550? I think the new ones are different but I could be wrong. I my case, the upper fireback is both cemented and bolted. There are two thru bolts that hold it in place and the seams are cemented. If my memory serves me, the bolts are actually removed from the outside on the back of the stove. It should be very evident where they are. Then you have to gently pry it off and angle it out correctly so that you don't damage the damper shaft that runs through the fireback and out the left side.

I will look for the link to the instructions. Don't know if I have it here at work or at home. Try google VC or Vermont Castings Encore 2550 Upper Fireback and see what you find online.
AGE
 
Thanks Age,
Yes I wrecked my entire weekend when I poked the hole in it. I don't know too much about stoves as it is, making this very aggravating. Thank you for taking the time to try and help.
 
You might try cutting a patch out of your old refractory box and cement it in place with refractory cement.
Just a thought. I have a model 0028 and saved my old one for that purpose. I also broke the shelf out of it,
and secured it with sheet rock screws. Seems to be holding up so far.

Has anyone ever tried building their own replacement out of refractory boards, cement, and screws?

As far as a leaking stove, I like to look for air intake leaks with a lit incense stick. I just move it around the
joints of the stove and see where the smoke is being drawn in.

I hope some of this helps.
 
A thought..... Would you be able to run the stove without the refractory unit in? I dont see why I could not?
 
A thought..... Would you be able to run the stove without the refractory unit or the cat in? I dont see why I could not?
 
Crispy said:
A thought..... Would you be able to run the stove without the refractory unit or the cat in? I dont see why I could not?

Yes, but you could only have small fires and thus only be using a small portion of the stoves potential. It would be akin to buying that car you've always wanted,
but never getting past second gear. I can't comment on any potential safety issues with doing this, but it seems to me that running it on bypass all the time would
also be circumventing the pollution fighting aspect of the catalyst.
 
I am going to order the parts tomorrow. I have my list of parts. I noticed the secondary air probe is not in the best shape so I am ordering that, and the gasket kit. Fire Honor Society, Thank You for your input.
Crispy
 
I wouldn't run the stove without the refractory. There are folks here who have built their own refractory package. I believe there is one guy who even provided dimensions and where he got sheet material. May have been an older model or an Acclaim. Can't remember. As for keeping the old... yup. Good idea. Finally Crispy, the secondary air probe is not in the best of shape? Did you acquire this stove in 2008 or was this stove new in 2008? I sure hope the latter because as part of my issue that I started in this thread, I too pulled/replaced my secondary air probe and other than a mere amount of wear, it was in near perfect shape. I replaced it because it was a relatively cheap part. I sure hope your stove is not two years old. Being that your are in RI, you won't need to run this thing for at least another month. ;)
 
Fire Honor Society..
Yes I purchased my stove in 2008 NEW right off the floor. It was the last one the guy had and sold me the floor model. I will take a picture soon and post it for you to see the secondary burner probe. It seems like I should replace it. I wish I had bought a simple stove to learn the art of burning. I have only burned for two seasons. I bought a new spliiter this season and was really getting into this whole way of heating my house. Then the refractory problem!!!!!!!
Crispy
 
The refractory is a fragile thing and is best treated tenderly.. like an old French car.
 
Ok.... Yesterday I got all the parts (refractory assembly, gasket kit, secondary probe) and I had a guy help me that does wood stove installations. He only charged me $100, so I thought it was a better safe than sorry deal. The upper fire back is cemented in place. I could have done it with out the tech there, but you live and you learn. You need to take out both side panels too. I replaced some of the gaskets that were showing wear. The toughest part was getting the hanging hood to attach to the upper fire back. It was the last step, but I had a hell of a time getting that back in. Lit my first fire later that night. The only thing going on now is some "puffing" every so often right out of the door on the top of the stove to drop the wood in.
Crispy
 
Yup... you have to gut the stove. Sorry. Thought that was obvious as the curve of the side panels don't give you the access to remove the upper fire back. No big deal right.. two bolts (internal) for each side. The back puffing is due to a build up of internal gases, tweak your air opened more on the right... a little love tap to give it just a smidgen more air. What temp do you burn at? I use both your standard classic griddle top therm and an IR just for the fun of it...
 
I broke a bolt while trying to remove the upper fire back... can I leave the fireback in place and cut the refractory assembly to re-install it?
 
Well that's just ugly. Sorry to hear that WarmME. My personal opinion is that cutting the refractory is counter productive to what it's intention is. I would assume that gas flow, heat, and draft would expose the seam of a cut refractory letting the gases leak through to the back of the stove and out the flue and reduce the efficiency and affect of the catalytic converter. Of course others might have a different opinion. Best of luck with this effort. Post back and tell us what you ended up deciding and doing.
AGE
 
Thanks for the input Fire Honor Society, I heeded your advice and pushed through getting the upper fireback off. I drilled out the bolt and was less gentle while trying to pry it off the back wall. I cleaned the stove out thoroughly and reassembled with the new refractory assembly. I started our first fire in it last night and it worked perfectly! We acquired the stove with a house we bought in June; everything in the house has needed work; thanks to this thread and http://legacy.vermontcastings.com/catalog/elements/files/2006/2003101_Fireback_5927.pdf we are at least warm.
 
WarmME - That's good news. Yes, the upper fireback is cemented in place along the channel but you obviously figured it out and performed a successful job. Remember that running this stove, like others, is an art rather than a science. You'll get the hang of it over the course of the burning season. That which started this thread is still a concern for me but last year, everything ran smoothly albeit still differently than the first seven years of her life. Anyway... I am enjoying NOT having fires yet. We broke all kinds of records over the past couple of days with it hitting nearly 86 on Saturday... So, I am just letting my seasoned wood enjoy the light breezes and bright sunshine and slowly moving some inside as I feel like it. Soon enough, I will start those small overnight fires I am sure. Oh, and by the way, our names are in the blue bar... those below the bar are Hearth.com's nomenclature for our level of participation on this site. You can call me AGE. Oh, and for all you 2550 owners out there, I ask this -- Where are we getting our parts these days? I hope to have another worry free year but you never can tell.
AGE
 
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