Catalyst clogged with I don't know what

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bucyeah

Member
Jan 8, 2018
12
Xenia, Ohio
I searched this formum and got some good info that directed me down the path of replacing my catalyst. I "inherited" a Vermont Castings Intrepid II 1990 in a house that I purchased last spring. In November I started burning the stove pretty much 24/7 with good results.

I the past few weeks, when engaging the catalyst, the file would snuff out and the stove top temp would immediately drop.

Since I wasn't sure how old the catalyst was, and expected that it was clogged, I ordered a new Steelcat from Condar.

When replacing it the old one was completely clogged. See attached pic with the new one sitting behind the old one for comparison.

IMG_20180110_183727_01.jpg


Is this normal fly ash deposit? I expected it to be more grey in color. Also, I expected a little bit of a deposit, I didn't expect a full pile.

I'm assuming this hasn't been cleaned in a while - the stove was manufactured in 2011 and was installed that year.

If not normal, is there something that I am doing wrong? I also bought a Catalyst thermometer and it shoots up to the 700-1350 degree range when the damper is closed and boy the heat output is good.

I just don't want to continue doing something wrong and end up with the same problem in 3 months and spend another $150 for a replacement catalyst.

Any advice would be appreciated.
 
That is crazy looking.
 
That is awesome! My progress would have stopped drafting long before that.

Don’t throw that old cat away. Just clean it and it would probably be fine if it was working good at the start of the season.

I’ll let vc owners comment on maybe some operation tips.
 
Unbelievable! I've never seen one that clogged! I clean my catalytic combustor at least monthly but sometimes more often depending upon how hard I am running the wood stove. Clean that old one and see if it still has some life in it.
 
How was that pile of crud clinging to the cat? Is it a big solid lump?

Normally my cat de-crudding advice would be "Hit it with a paintbrush or a shop vac", but that's in a whole new category for me.
 
I searched this formum and got some good info that directed me down the path of replacing my catalyst. I "inherited" a Vermont Castings Intrepid II 1990 in a house that I purchased last spring. In November I started burning the stove pretty much 24/7 with good results.

I the past few weeks, when engaging the catalyst, the file would snuff out and the stove top temp would immediately drop.

Since I wasn't sure how old the catalyst was, and expected that it was clogged, I ordered a new Steelcat from Condar.

When replacing it the old one was completely clogged. See attached pic with the new one sitting behind the old one for comparison.

View attachment 220401

Is this normal fly ash deposit? I expected it to be more grey in color. Also, I expected a little bit of a deposit, I didn't expect a full pile.

I'm assuming this hasn't been cleaned in a while - the stove was manufactured in 2011 and was installed that year.

If not normal, is there something that I am doing wrong? I also bought a Catalyst thermometer and it shoots up to the 700-1350 degree range when the damper is closed and boy the heat output is good.

I just don't want to continue doing something wrong and end up with the same problem in 3 months and spend another $150 for a replacement catalyst.

Any advice would be appreciated.
700-1350 is normal cat temps
 
Holy Moly! This definitely looks like it was cleaned with the cat in it or something got stuck in the flue and caused this to happen!
 
Hold on, here... exactly what is that material sitting atop your old combustor, and in which orientation was it installed? To me, it does not appear to be creosote. It does not appear to be fly ash. If I had to guess, based on the color and consistency in that photo, it’s probably crumbling refractory material from within the stove. You need to get in there, and post a photo of the refractory combustor chamber.

My best guess, your refractory cat chamber is toast. Whether that happened from an animal getting in there (is your chimney capped?), overfiring, or just sheer age, is only a guess at this point.

At least they're cheaper than Jotul's (by 2x!): https://www.ebay.com/itm/Vermont-Ca...-Intrepid-II-Winterwarm-1602527-/253294043016
 
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Ashful, thanks for the reply.

That was my original question, didn't look like ash to me..

I have a fire burning now so can't take a picture, but that sounds reasonable.

The chimney is capped, and the stove in the house, so no animals, but the overfiring I can't say since the stove was here when I moved in. The rectory ironically is the same color d that crap.

The orientation in the stove is just like it sits in the picture. Crap was on top when I pulled it out.
 
based on the color and consistency in that photo, it’s probably crumbling refractory material
That's what I thought but I don't have experience with that particular stove. My Dutchwest 2460 has a refractory cap over the cat in the top of the stove, and it's about that color..
 
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Would somebody please explain exaclty what does the refractory material do? I have a cat stove but no refractory material.
 
Would somebody please explain exaclty what does the refractory material do? I have a cat stove but no refractory material.

Those combustors can sometimes hit temperatures over 2000F, and some stove designs need them to be well insulated, so you need something other than the usual steel or cast iron to house the combustor. So VC (Dutchwest) and Jotul decided long ago to use glued up refractory panels to build these cat chambers. It’s an excellent material for taking high temperature, and providing insulation or air passages, but it is an unfortunate combination of soft and brittle, like damp chalk.

I had a squirrel get into one of my Jotuls, thru the chimney, and completely trash the main refractory chamber. Jotuls price for new refractory is about $600, so the VC parts seem cheap, by comparison.
 
Ok thanks for the description. I guess I don't understand why one stove company chooses to use delicate but expensive material when another company does not and the stoves themselves are not that different in price.
 
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I guess I don't understand why one stove company chooses to use delicate but expensive material when another company does not and the stoves themselves are not that different in price.
Excellent question!
 
Ok thanks for the description. I guess I don't understand why one stove company chooses to use delicate but expensive material when another company does not and the stoves themselves are not that different in price.
And that's part of the reason why there aren't more VC's in peoples houses. Rather than re-engineer a stove to meet the new epa emissions rules, VC took there older style castings and fudged them to make them work to get the epa sticker, built not to last.
 
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Ok thanks for the description. I guess I don't understand why one stove company chooses to use delicate but expensive material when another company does not and the stoves themselves are not that different in price.
@kennyp2339 gave a good answer, which probably covers at least a few of the stoves built this way. However, you have to remember this material is not expensive. It's sold in sheets, and then VC or Jotul would cut the sheets and glue up these complex chambers. So, most of the original cost was in the labor, not the material. However, the reason they cost so much today (at least Jotul) is that they keep raising the prices on most of their repair parts each year, as these old obsolete stoves age. I suspect the primary chamber, which Jotul sold for $240 in 2011 and $450 in 2014, was probably only $100 back when the stove was in production (1980's).
 
@kennyp2339 gave a good answer, which probably covers at least a few of the stoves built this way. However, you have to remember this material is not expensive. It's sold in sheets, and then VC or Jotul would cut the sheets and glue up these complex chambers. So, most of the original cost was in the labor, not the material. However, the reason they cost so much today (at least Jotul) is that they keep raising the prices on most of their repair parts each year, as these old obsolete stoves age. I suspect the primary chamber, which Jotul sold for $240 in 2011 and $450 in 2014, was probably only $100 back when the stove was in production (1980's).

Adjusted for inflation, the 2011 price is the cheapest of the lot, even lower than $100 in 1980!
 
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Priced it for my VC stove, anywhere from $196 - $250 for the chamber and the cover panel. Still beats the price of buying a new stove.

Has anyone replaced the refractory chamber in their VC stove?
 
A lot of guys in the VC owners thread have. Jharkin detailed his rebuild quite well.
 
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