Thoughts on the new(ish) hybrid cat designs?

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Jun 1, 2019
59
MN
It looks like Lopi, Hearthstone, and now Jotul are going the route of a hybrid cat design to meet 2020 regs. Maybe there are more already; I’m guessing more will follow.

Do you guys have any thoughts about these designs?

It’s unclear to me what the advantage is over a fully cat system like a Blaze King.
 
Woodstock would probably be the way to go in a hybrid. Their steel stoves have welded seams, of course, but they ain't real purty. The Progress Hybrid is a soapstone doll, but you may eventually (at 15-20 years) have to rebuild the stove to re-cement the seams, or at least patch them like I did on the used Fireview that my SIL bought.
 
The advantage of a hybrid would be that you could run secondary-burn to get a cooler flame show and faster heat, if you don't burn 24/7. You can also run flame in the box on a straight cat but you won't have flames in the top of the box, shooting off the secondary.
I've never seen a PH in action though, so I don't know what that looks like..
 
Regency also has made some hybrids for a few years now. We will probably see more in the coming year. Not all stove companies will take this route and some do it better than others. It's one method of achieving cleaner burning.
 
So, I ask because my wife has her heart set on a Hearthstone Manchester, and I can get either the old model or the 2020-certified model with the cat. I'm usually one to go with the new technology, and I like the idea of being able to turn it way down overnight, but ... it's new and untested.
 
You know about as much as we do about how well the stove will perform over time. Some companies like Woodstock, Regency and Lopi have had hybrids on the market for a while now so it's not new. But some implementations have worked out better than others. We'll have to wait and see. Regardless of the stove look for things like how well the cat is protected from flame impingement, how easy is it to service the cat and if the cat is proprietary or not.
 
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The cats in the prototype stoves I saw at the trade show had no protection at all. Front and center...
Keep in mind, these hybrid stoves aren’t designed so you can burn them low and slow, the cat is there to scrub the exhaust for the most part, they do not run low like a traditional cat stove. They aren’t adding a cat to make your life easier, but only to meet new emissions standards..
Woodstock has done a decent job of getting a low burn. Others not so much that I’ve seen.
 
From what I understand the hybrid allows for a cleaner burn across a wider range of BTU output.
It might also allow for advertising and maybe even building a broader output range stove.
 
We installed a new Hearthstone Castleton hybrid today. They have moved the cats, yes 2 of them way back. They now aren’t in the flame path, but are out of reach for cleaning. To clean the steel cats you’ve got to remove a cotter pin (which most of the time isn’t reusable) remove the baffle retainer, pull the baffle out through the door. If more room is needed you can pull the center burn tube by removing another cotter pin. I’m glad to see they moved the cats back, and that the baffle is removable at least, the older models it wasn’t removable... Too bad it will be such a big deal when the cats get clogged with ash.
 
Another interesting thing or two: the cats don’t use interim gasket, rather cerimac wool strips. The bypass is very small, and doesn’t have a latch or detent of any kind, no gasket either.
 
Woodstock would probably be the way to go in a hybrid. Their steel stoves have welded seams, of course, but they ain't real purty. The Progress Hybrid is a soapstone doll, but you may eventually (at 15-20 years) have to rebuild the stove to re-cement the seams, or at least patch them like I did on the used Fireview that my SIL bought.

Progress is a steel stove with soapstone on the outside. My guess is it won’t need much more than gaskets. :)
 
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So now it has a bypass at least, I like the reusable cat gasket, my old hearthstone had the cotter pin and it was no big deal to buy 100 of them. Are the two cats big like a regular princess cat or are they two little ones? Gosh this reminds me of those old failed add on cat designs that were obvious afterthoughts.
 
So now it has a bypass at least, I like the reusable cat gasket, my old hearthstone had the cotter pin and it was no big deal to buy 100 of them. Are the two cats big like a regular princess cat or are they two little ones? Gosh this reminds me of those old failed add on cat designs that were obvious afterthoughts.
The cats are pretty small. I didn’t get the impression the gasket was reusable either. The owners manual detailed replacing the gasket if the cats were removed. The cotter pins are a PITA.
 
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Progress is a steel stove with soapstone on the outside. My guess is it won’t need much more than gaskets. :)
Sheesh, I think that's at least the second time that someone has had to correct me on that. The PH is even more awesome than I thought! ;)