2.5mo old catalyst and refractory...this is bad.

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.

kentuckydiesel

New Member
Sep 29, 2012
12
Back in October I purchased a new catalyst, refractory, gasket kit, and secondary air probe for my VC Encore 2190 through Hechlers online. After installing the new parts, and making sure everything else was in good shape, it was operating like an entirely different stove.

After spending over $500 for all these parts, my wife and I have been VERY careful with the stove temps. While we don't have a cat probe, we have a surface thermometer on both the griddle, and the side of the stove-back, where the hot gasses leave the refractory. We NEVER allow the griddle temps to get over 650, and NEVER let the temp at the stove back to get over 700 (I have been told that 600 is ideal on the back thermometer).

A few weeks ago I noticed the catalyst temps weren't staying up when we turned down the primary air like they had been. I thought the catalyst might have some ash blockage, so I let the stove die down overnight and went to clean it the next morning. What I found was pretty disturbing given the money we just spent a couple months ago, and the care we have taken to keep everything in good shape.

The can on the new catalyst had warped so badly on the corners that it broke the sides out of the new refractory! catalyst 1.JPGrefractory2.JPGrefractory1.JPG

What's worse? I just called Hechlers and they told me that there is no warranty for can warpage. He recommended that I cut the can off the catalyst and use stove cement to patch the refractory. :O

When I reminded the guy that these parts are only a couple months old and this SHOULD NOT have happened, he gave me the number for Applied Ceramics (who they buy catalysts from) and told me that they handle the warranties on their catalysts directly. Unfortunately all I got was a voicemail, so I'll just have to wait and see how this comes out.

Has anyone else had this issue with a catalyst this new? I am well aware that stainless (which I believe the can was made of) is prone to warpage, as I run a shop which does a great deal of work with #304 stainless), but to me, this is very much a flawed can design if it warps this much in a couple months of proper temperature range woodburning.
The can on the original catalyst from the mid-90's (the previous owner of the stove never changed it), was bowed, but nothing like this.

Thoughts? Advice?

Thanks,
Phillip
 
Oh crap, and I just bought a new Buck 80 cat insert. I ain't gonna sleep tonight!:confused:
 
Bummer. It sounds like you've done everything right. I'm surprised at the casual response from the stove shop. Was this from the owner?

Unfortunately it sounds like a repair with some refractory cement and replacing the defective cat with a non-stainless one is the only recourse to get you heating again without delay. I would carefully insert some "pins" into that right side to reinforce the refractory repair.
 
Oh crap, and I just bought a new Buck 80 cat insert. I ain't gonna sleep tonight!:confused:

Relax, there's no refractory in that unit to my knowledge.
 
I'm feeling much better, thanks:cool:
 
From using a digital temp gauge w/ probe inside the flue, and a magnetic mount gauge on my flue... I would recommend everyone get an actual probe thermometer.

I've had spikes of over 1200F in flue temps since I started using the digital readout... set it the digital gauge to alarm at 1200F if I've walked upstairs. Stove can be cranking out 1200F, and the flue surface temps are still only 300-400F.

Just something to think about.
 
Bummer. It sounds like you've done everything right. I'm surprised at the casual response from the stove shop. Was this from the owner?

Unfortunately it sounds like a repair with some refractory cement and replacing the defective cat with a non-stainless one is the only recourse to get you heating again without delay. I would carefully insert some "pins" into that right side to reinforce the refractory repair.

I'm not sure if it was the owner or not...sounded like the same guy I talked to when I called to check on my order way back when.

The cat itself wasn't stainless...ceramic with a stainless (I believe) can, same style as OE...and might be OE for all I know.

-Phillip
 
From using a digital temp gauge w/ probe inside the flue, and a magnetic mount gauge on my flue... I would recommend everyone get an actual probe thermometer.

I've had spikes of over 1200F in flue temps since I started using the digital readout... set it the digital gauge to alarm at 1200F if I've walked upstairs. Stove can be cranking out 1200F, and the flue surface temps are still only 300-400F.

Just something to think about.

Thermometer wasn't on the flue itself...it was on the stoveback. Basically just on the other side of a piece of steel from where the hot gasses from the catalyst exit the refractory. I've found that thermometer to be very responsive to changes in primary air adjustment, where a thermometer on the flue itself shows very little change.

-phillip
 
I also recommend a flue thermometer, no doubt. We can't use a surface gauge because it's useless on my stove (cast iron plates over steel stove) and our chimney pipe is only single wall the first 18" out of the stove, rest is double wall up to triple wall to the roof. We had NO idea how hot we were running our fires the first few times until we got the probe! Be safe, flue temps tell you a lot about how hot/cold you're burning immediately, load to load, the stove top temps can take a while to change ;)
 
I doubt you'll have much luck cementing back together the refractory. Once the refractory surface has been exposed to fire it doesn't seem to want to take cement anymore. And general-purpose stove cement isn't up to the job either - you really need proper (and expensive) refractory cement.

We had a cat, one of the SS ones, warp and start falling apart in 3 months. The manufacturer replaced it. You may have better luck getting a new cat under warrantee from the cat manufacturer than a new refractory box from VC, as the cat manufacturers are fairly philosophical about returns. The long skinny VC cats seem especially vulnerable to warping, compared to the round ones, and to a lot of damage when they do since the refractory is so fragile. Dumb design, if VC had thought of sandwiching the cat between iron plates like the Woodstock does we'd still be happily burning our Encore.

It only takes one or two episodes of overfiring to start the destruction of the cat and refractory box. After we trashed the first refractory package in our Encore we got a lot more careful about how we ran the stove, but it didn't seem to do any good - the rebuild only lasted half the time the original one did., and the next rebuild even less. We finally gave up on the stove rather than put more money in to it. Ssad to throw away 500 lbs of gorgeous cast iron for the want of a viciously overpriced 2 lb. refractory box.
 
Oh crap, and I just bought a new Buck 80 cat insert. I ain't gonna sleep tonight!:confused:
You don't have a refractory package in the Buck, if I recall correctly.
 
From using a digital temp gauge w/ probe inside the flue, and a magnetic mount gauge on my flue... I would recommend everyone get an actual probe thermometer.

I've had spikes of over 1200F in flue temps since I started using the digital readout... set it the digital gauge to alarm at 1200F if I've walked upstairs. Stove can be cranking out 1200F, and the flue surface temps are still only 300-400F.

Just something to think about.
Yeah Im not sure the stove top temp has a direct relation to the cat temp. I thought all cat stoves had a place to put a probe thermo?
 
Update on this issue...

Not long after my last post, I sent a detailed e-mail to Mike at Applied Ceramics. He called me back the next business day and discussed the issues with me for over an hour. While he was very polite and friendly, he did try to give me every explanation in the book as to how I did something to damage the catalyst.
(In his defense, I always go over everything that could be wrong on my customer's end before looking at the manufacturing end...just because it's usually something the customer didn't understand)
After explaining to him that none of this could have occurred and discussing the extreme warping of the steel and how it shouldn't have happened if the correct material was used, he told me he would have to talk to some others in his company to get more info.

The next morning I sent Mike a second e-mail with some data and a chart proving my point regarding the correct steel to use. (I run the family steel fabrication shop, 6th generation in the business) I showed him that anything less than austenitic stainless steel (300 series) would loose it's tensile strength and warp out of control above 800-1000 degrees, and that anything less than #304 stainless would scale and disintegrate over time due to the heat. Further, I also showed that at 2100 degrees (the melting temp of cast iron), the band around the catalyst, if made of the proper steel, should have only expanded two thousandths of an inch

I got a call back from Mike that afternoon saying that Vermont Castings was going to send me a new catalyst/refractory package, but he wasn't sure what was wrong or why they were taking care of the issue rather than Applied Ceramics.
Two weeks went by and I didn't hear anything...until yesterday. I got a call from a guy at Vermont Castings. He apologized for taking so long to get back to me, and told me that he was sending the catalyst/refractory package out that day.

As we were about to get off the phone, he said..."Oh, by the way, did you ever hear what the problem was with the catalyst?" I told him I hadn't. He said, "Well, we had been making them here, in house. It turned out that we were using a much lower grade of stainless than we should have been."

....So, now that Vermont Castings has the info they need and they are using the proper grade of stainless, I'm thinking they should be much better. Time will tell.

-Phillip
 
Good on you...

Just a matter of opinion here, but they really need to have qualified people doing material selection (or at least review) prior to selling to the public. It would make sense at the very least to reimburse you for your original purchase, and perhaps keep you on retainer to do future engineering/design for them. You (and us as well) may find humour in invoicing them for your services.

You can honestly say you made a difference in the world today. :) Hopefully they take the stock off the shelf and don't sell to other less knowledgeable persons (pretty much everyone would fall in that category I'd assume).



Update on this issue...

Not long after my last post, I sent a detailed e-mail to Mike at Applied Ceramics. He called me back the next business day and discussed the issues with me for over an hour. While he was very polite and friendly, he did try to give me every explanation in the book as to how I did something to damage the catalyst.
(In his defense, I always go over everything that could be wrong on my customer's end before looking at the manufacturing end...just because it's usually something the customer didn't understand)
After explaining to him that none of this could have occurred and discussing the extreme warping of the steel and how it shouldn't have happened if the correct material was used, he told me he would have to talk to some others in his company to get more info.

The next morning I sent Mike a second e-mail with some data and a chart proving my point regarding the correct steel to use. (I run the family steel fabrication shop, 6th generation in the business) I showed him that anything less than austenitic stainless steel (300 series) would loose it's tensile strength and warp out of control above 800-1000 degrees, and that anything less than #304 stainless would scale and disintegrate over time due to the heat. Further, I also showed that at 2100 degrees (the melting temp of cast iron), the band around the catalyst, if made of the proper steel, should have only expanded two thousandths of an inch

I got a call back from Mike that afternoon saying that Vermont Castings was going to send me a new catalyst/refractory package, but he wasn't sure what was wrong or why they were taking care of the issue rather than Applied Ceramics.
Two weeks went by and I didn't hear anything...until yesterday. I got a call from a guy at Vermont Castings. He apologized for taking so long to get back to me, and told me that he was sending the catalyst/refractory package out that day.

As we were about to get off the phone, he said..."Oh, by the way, did you ever hear what the problem was with the catalyst?" I told him I hadn't. He said, "Well, we had been making them here, in house. It turned out that we were using a much lower grade of stainless than we should have been."

....So, now that Vermont Castings has the info they need and they are using the proper grade of stainless, I'm thinking they should be much better. Time will tell.

-Phillip
 
Nice that you got satisfaction, but how about all the others (myself included) who have had their VC stoves and cats meltdown after a couple years - prematurely, but long enough that VC and applied could blame it on operator error. A cat that warps at normal temperatures because its made of the wrong metal looks just like a cat made of the right metal that was badly overheated

You got to wonder how long they have been using the wrong metal for the cats, and whether VC has similarly been cheaping out on the metal they use for the SS parts like the deflectors and the heat exchanger, since warping of these parts is often the cause for the refractory box failing.

Class action suit time?
 
I do not have much respect for the modern VC company. I fully expect that they have produced many of these cats with improper metal. I fully expect that they will sell the stoves as if nothing was wrong and then hope that nothing goes wrong during the warranty period. If something fails and they can't blame somebody else then they will replace the part per the warranty terms. The majority of people won't get the free replacement so VC makes money on the deal.

Reminds me of the movie Tommy Boy where Chris Farley says that you can slap a warranty on a box of crap but what the customer really wants is good brake pads, or something like that.
 
  • Like
Reactions: Oldhippie
Good Job!
 
I have to say, I don't think that they had been using the wrong stainless for too long. The original cat was in my stove when I bought it last year (previous owner had never changed it in the 20 years he had the stove), and while it had warped to some degree and did break the sides out of the original (extremely brittle) refractory, it wasn't warpage like I had on this new one...not even close. Also, the previous owner had definitely overfired the stove...upper fireback (damper) was warped pretty badly.

Bet it was a recent case of some person in purchasing making a bad decision.

I still wonder if I shouldn't go ahead and re-can the cat myself using some heavier gauge #304 stainless before installing it in the stove.


-Phillip
 
Nice that you got satisfaction, but how about all the others (myself included) who have had their VC stoves and cats meltdown after a couple years - prematurely, but long enough that VC and applied could blame it on operator error. A cat that warps at normal temperatures because its made of the wrong metal looks just like a cat made of the right metal that was badly overheated

You got to wonder how long they have been using the wrong metal for the cats, and whether VC has similarly been cheaping out on the metal they use for the SS parts like the deflectors and the heat exchanger, since warping of these parts is often the cause for the refractory box failing.

Class action suit time?

I will say that my deflectors are in great shape and looking at the original cat, I don't think there would have ever been any warping so long as it had been changed when it needed to be...it was simply well beyond the hours of service it was designed for.
The new cat though...it had obvious warping within the first month or so...it wasn't until month two that I found out just how bad it was.

As far as class action suits, that never helps anyone. There are a number of people relying on that company to feed their families. In contrast, a warped steel band didn't cause any of us to go hungry...just made our wood stoves less efficient.
VC makes good stoves, and it sounds like they do want to fix problems. Just have to talk to the right people and have the right info.

-Phillip
 
Another update...Got the new parts!

I am going to assume that VC either gave up on canning their own cats, or they are taking a good hard look at their materials/process. New cat is from Sud-Chemie.

Let me tell you guys this. The Sud-Chemie stainless Stainless can/wrap is heads and tails above the last one I got. Heavier gauge, and TIG welded all the way down the seams on the ends rather than just tack-welded in three places like the last one.

On a side note, they accidentally sent me a Refractory for a 0028/2140 rather than my 2190. I like the design of this one better. Anyone know if it will fit in my stove if I make an access plate for the back?

-Phillip
 
How will you make an access plate on a cast Iron stove? Better get the correct parts.
 
Phillip, get the right parts for your stove. If there are future issues this might become a point of dispute.

And thanks very much for contributing both to the discovery of the cause and solution for this issue and especially for sharing this information. You've helped a lot of folks, including those at VC making the stove. Well done.
 
  • Like
Reactions: webby3650
The back of the stove (where the access plate is on the 0028 and 2140) is made of steel rather than cast. Either way, I would make an access plate out of 3/8 thick steel, then make the opening in the back part of the stove on a vertical mill.

Will take a look at the old parts and figure out which direction to take.


-Phillip
 
The back of the stove (where the access plate is on the 0028 and 2140) is made of steel rather than cast. Either way, I would make an access plate out of 3/8 thick steel, then make the opening in the back part of the stove on a vertical mill.

Will take a look at the old parts and figure out which direction to take.


-Phillip
No, the heat shield is steel, but the stove is cast. All Encore's, and VC's for that matter, are cast. Hence Vermont Castings.
 
VC got away from the rear access to the cat, they improved it by giving access from the inside of the stove. It's an improved, simple design. Why take it back to an inferior design? Not to mention compromising it's structural integrity.
 
Status
Not open for further replies.