Well friends, it's been a fun couple of days over here. If you recall, Post #137 in this thread I shared a picture of a warped catalyst pulled from my VC Defiant. We all got a chuckle out of it, and I think
@Woodsplitter67 even told me I won first prize for "never saw that before".
Welp....happened again! And only after 6 weeks of use. I noticed my cat temps were recently sluggish, hanging in that 900 range and lots of smoke in the exhaust. So, I pulled the stove apart and voila! another warped catalyst!
So, after some conversation with Midwest Hearth - and let me be clear,
their customer service is fantastic and since they aren't the manufacturer of the catalyst and just a reseller I don't think they are at fault - but we were discussing a potential "hot spot" in my secondary with a root cause of an air leak somewhere. I found this odd as the Auber Probe is only about 1 inch away from where the warping on both of these catalysts occurred. They consider over firing the catalyst to be anything above 1600. But nonetheless, I've been searching and searching these last few days and ordering in gaskets and tightening anything that can be tightened. Midwest Hearth mailed me out another catalyst as a "one time replacement".... meaning I'm not getting another discounted one and the next one is full price. Understandable....I have an MBA, that's a business decision.
However, I've now done a little catalyst comparison......
Catalyst #1 in this picture was the original metal catalyst I purchased in December 2022. It was in operation from December 2022 through December 2024, when overall performance appeared to decline. This Catalyst retained it's structural integrity, but failed to reach optimum operating temperatures. I
n comparing this catalyst to the others in the picture, there is an observable difference in the build of the Side Walls. Catalyst #1 is more reinforced and thicker then Catalyst #2 and #3, with an overlap of the metal to the top and bottom of the honeycomb.
Catalyst #2 in this picture was a catalyst ordered with warranty discounting in late December 2024. This catalyst survived almost a year in my stove (granted I think last winter here was substantially warmer than this year and I burned a lot less wood). This catalyst lost it's ability to maintain optimum temperatures this past December 2025 , which led to my discovery of structural warping (Post #137 in this thread). I certainly saw temps in the 1500-1600 range on this catalyst for short periods. Highest temp was probably something like 1612, which I let ride and it came down after about 20 minutes. But by the definition, this is over-firing above 1600.
Catalyst #3 in this picture was a catalyst ordered December 2025 also with warranty discounting. This catalyst survived
6 total weeks in my stove. The highest temperature I have seen on this catalyst in those 6 weeks was 1456. The catalyst all the way up until my most recent clean out was achieving temps in the 1000-1250 range, but I was seeing lots of smoke out of my chimney which made me look at that catalyst. Warped in almost the same location as Catalyst #2. This is identified by the Red Arrow when you look at the catalyst in the picture sitting within the secondary chamber (left side, and in the back of the catalyst).
So all that said - anybody have any thoughts? I've emailed this information back out to midwest hearth and I'm sure they're going to respond. Interestingly enough - I do not see the Metal Catalyst for the Defiant/Encore available for sale on their website. Only the Ceramic is available. The metal catalyst is available there for the Dauntless. Whether the Defiant/Encore metal is sold out, or they've stopped selling it is unknown.
GO PATRIOTS
!
