Warped VC Encore Catalyst

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SammyBwood

New Member
Jan 23, 2023
11
Birchwood WI
I purchased 2 replacement catalysts from Condar, one to have as a backup, for my VC Flexburn Encore. After only a month of use, I noticed that the steel frame of the catalyst was warped (see picture). I replaced it this past weekend with my backup. After 2 days of use, I checked on it this morning, and this one is also warped. I'm burning oak with a 14 - 18% moisture content. I don't believe I'm letting the cat get too hot. The original cat lasted 4+ years and I only replaced it because some of the cell walls were falling out/thermal shock. I attribute this to a friend who was staying here that tried to be "helpful" by loading my wood stove one day without disengaging the cat, leaving the doors open, tossing in cold wood.
Anyone else have this problem? Are they defective? I unfortunately bought the $129 model "with no warranty" because the others were sold out. It's hard to find this cat given it's the 1" model.

[Hearth.com] Warped VC Encore Catalyst
 
Well it's good you got your original one to last 4 years. That's darn good. If you checkout the VC Owners thread, you'll see more than a few posts of people complaining about their cat area overheating. It's darn common for VC stoves, and there's a guy who rants about this on youtube who eventually got rid of two VC stoves because of this. I dont have the answers, but all I can say to you is have you been doing anything differently, what changed since you had that original cat that lasted so long? Even a group of trees removed near a house can have a significant impact to ones draft for example and people dont think about that. My cat gets into the danger zone quickly and easily, but if I have a great bed of coals before reloading full, it tends to stay just below then drops to a modest level throughout the burn. Just one tick down on my air control too early and Im sending too much heat through the secondary and that will spike temps. It's why I removed my cat for usage during shoulder seasons where Im hoping that it will help me reduce some of the low burn creosote that will accumulate inside my flue pipe. I dont have a ton of experience with stoves and my VC Dauntless is my first stove. I really struggled at first but have it fairly well dialed in at most times.
 
Well it's good you got your original one to last 4 years. That's darn good. If you checkout the VC Owners thread, you'll see more than a few posts of people complaining about their cat area overheating. It's darn common for VC stoves, and there's a guy who rants about this on youtube who eventually got rid of two VC stoves because of this. I dont have the answers, but all I can say to you is have you been doing anything differently, what changed since you had that original cat that lasted so long? Even a group of trees removed near a house can have a significant impact to ones draft for example and people dont think about that. My cat gets into the danger zone quickly and easily, but if I have a great bed of coals before reloading full, it tends to stay just below then drops to a modest level throughout the burn. Just one tick down on my air control too early and Im sending too much heat through the secondary and that will spike temps. It's why I removed my cat for usage during shoulder seasons where Im hoping that it will help me reduce some of the low burn creosote that will accumulate inside my flue pipe. I dont have a ton of experience with stoves and my VC Dauntless is my first stove. I really struggled at first but have it fairly well dialed in at most times.
The only thing I'm doing different is that I'm trying to get a longer burn by taking the primary air as low as 20%. I've never been able to get more than 4 hours out of a load of wood and am jealous of the posts I've seen of others who can run at 20%. So, I found a few great resources that indicate that once the stove gets to temp (550°), I can engage the cat. Leave the primary air on High for no more than 30 minutes (I barely go 15), then adjust the primary downward when the indicator is in the Operate range at the back of the stove. They said that once the cat is operating, it will keep itself hot enough to keep going, even though the main temp will fall. I wouldn't think that could have caused the warping of the frame unless I unwittingly let it overheat, but it never gets above the "A" on Operate (sad - I wish it was a true thermometer).

I have a love/hate thing going on with this stove. She's fickle. I just wondered if it was a quality issue with the steel framing on the cat. I've seen other cats with a metal cross member that is wrapped around the cat, like a belt around your waist. It would seem that would hold it together.
 
Well it's good you got your original one to last 4 years. That's darn good. If you checkout the VC Owners thread, you'll see more than a few posts of people complaining about their cat area overheating. It's darn common for VC stoves, and there's a guy who rants about this on youtube who eventually got rid of two VC stoves because of this. I dont have the answers, but all I can say to you is have you been doing anything differently, what changed since you had that original cat that lasted so long? Even a group of trees removed near a house can have a significant impact to ones draft for example and people dont think about that. My cat gets into the danger zone quickly and easily, but if I have a great bed of coals before reloading full, it tends to stay just below then drops to a modest level throughout the burn. Just one tick down on my air control too early and Im sending too much heat through the secondary and that will spike temps. It's why I removed my cat for usage during shoulder seasons where Im hoping that it will help me reduce some of the low burn creosote that will accumulate inside my flue pipe. I dont have a ton of experience with stoves and my VC Dauntless is my first stove. I really struggled at first but have it fairly well dialed in at most times.
By the way, GrumpyDad - thank you for the heads up on the VC Thread. I'll follow that one. Misery loves company.
 
The only thing I'm doing different is that I'm trying to get a longer burn by taking the primary air as low as 20%. I've never been able to get more than 4 hours out of a load of wood and am jealous of the posts I've seen of others who can run at 20%. So, I found a few great resources that indicate that once the stove gets to temp (550°), I can engage the cat. Leave the primary air on High for no more than 30 minutes (I barely go 15), then adjust the primary downward when the indicator is in the Operate range at the back of the stove. They said that once the cat is operating, it will keep itself hot enough to keep going, even though the main temp will fall. I wouldn't think that could have caused the warping of the frame unless I unwittingly let it overheat, but it never gets above the "A" on Operate (sad - I wish it was a true thermometer).

I have a love/hate thing going on with this stove. She's fickle. I just wondered if it was a quality issue with the steel framing on the cat. I've seen other cats with a metal cross member that is wrapped around the cat, like a belt around your waist. It would seem that would hold it together.
yea thats exactly what someone did in the vc thread, they put stainless bands around it because their cat was warping too. Then they ordered a steel cat thinking that might help but have not received it yet.
I see absolutely zero value in operating my cat during normal operating temperatures which for me are above 450 and below 600. I try to stay at 500 STT. It gives off even heat, and if it gets too hot in that room then I can always open a window and lower the air control a bit. Having a fan blow INTO the stove room per these forums (opposite of what I thought) has helped move some of that heat into the other room. Most of the time though through winter, I do not have the issue of too much heat. Once I hit 70-72 degrees in that room, it's hard to go higher without really heating up the stove and getting minimal burn time. I get ~6 hours burn on my stove, maybe a bit more if I were careful on how I load. I try to do 3/4 - 7/8ths of a load with careful placement of the wood to cross abit over each other in a not so perfect E/W arrangement of wood. I know the stove can do 8 hours if I full pack it, and have some oak in there and I dont exceed maybe 475-500 for the majority of the burn.
^That's with air control about midway, to a notch or two below midway...maybe that's like 30-60% air control would be my degree of motion for my air control during steady runs. Obviously during startup and reload I must move air control to high for a period of time to catch my wood.
 
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Might have something to do with it being a 1" thick cat, mine is 2". A true temperature probe will tell you cat temps and they will see 1500-1600 pretty often so I'd say that's what makes that thin stainless warp. This is a pic of my old cat, probably 6-7 years old at least, lost track probably older than that.

[Hearth.com] Warped VC Encore Catalyst
 
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Might have something to do with it being a 1" thick cat, mine is 2". A true temperature probe will tell you cat temps and they will see 1500-1600 pretty often so I'd say that's what makes that thin stainless warp. This is a pic of my old cat, probably 6-7 years old at least, lost track probably older than that.

View attachment 308883
I was wondering if I could substitute the 2" high cat for my 1". Seems the 1" is for the flex burn. Are you substituting or did this come with a 2"? I can only find a metal 1 " now. I'm using one of the warped cats for now.
 
I was wondering if I could substitute the 2" high cat for my 1". Seems the 1" is for the flex burn. Are you substituting or did this come with a 2"? I can only find a metal 1 " now. I'm using one of the warped cats for now.
My stove is a 0028 Encore and that's the factory size. Mine has a panel on the back held by 4 bolts that you remove to install the cat.