DIY non-catalytic to catalytic

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But to fit a cat in a tube stove you will need to tear out the tubes and baffles to fit a cat and bypass to gain what?
I asked because I saw that post I linked. I have no idea what it takes, but it did not look like an inline flue cat. it looked like add-on to make it a cat stove. you would have to pose your question to that company. it might or might not work better, but I have not ever made modifications, so I cannot add comment
 
you keep asking, and I will tell you that a I linked the company that makes an aftermarket. I am as curious as you, but you keep asking me
Yes but you didn't ask about installing a premade kit into an old smoke dragon. You specifically asked about doing it to a noncat epa stove.
 
Yes but you didn't ask about installing a premade kit into an old smoke dragon. You specifically asked about doing it to a noncat epa stove.
you are right, I just asked, because I did not understand what I saw. that is all. this does not need to turn into a final exam
 
go ask that manufacture and that vendor. they might answer you, but I would like to ask you to stop harassing me
I didn't realize having a discussion was harassment. That device is made for pre epa and unlisted stoves. It's totally different
 
you are showing off
No you asked a question and I am trying to get you to realize that doing what you proposed makes no sense financially or in terms of efficiency.
 
No you asked a question and I am trying to get you to realize that doing what you proposed makes no sense financially or in terms of efficiency.
I proposed nothing. I asked a question to be answered based on a link I found on your forum. this is odd inquisition behavior from a mod no less. you people are creepy
 
I proposed nothing. I asked a question to be answered based on a link I found on your forum. this is odd inquisition behavior from a mod no less. you people are creepy
Ok but your question was about listed epa approved stoves. The link is a product for unlisted pre epa stoves
 
I think having a cat to clean up flue gases (and not producing significant additional heat that is released into the room) is fine. But if you have a tube stove, that cat is best in the flue in order not to mess with the gas flow design that makes.the tubes work (i.e. produce heat and clean exhaust).

So, if you have a tube insert, I'd not bother - it should be working to a similar efficiency as a cat system already.

If it's an old stove with neither tubes nor cat, yes, it can help cleaning up exhaust.

An issue is that cats increase impedance for gas flow and thus you need higher draft to have the stove burn in a similar way.

Before doing so (and after having design drawings), I'd ask *in writing* to have approval of your insurance company and local code enforcement.
 
Most better noncats have a deflector above the baffles doing exactly that. It increases dwell time

Mine does, but it still not as effective as it could be.

I argue the whole dwell time concept, it's about allowing the gas to touch the cold parts of the firebox to allow heat transfer. Industrial heat exchangers are designed to allow the working fluids to touch the most surface area in the least amount of time possible to increase total heat transfer.

But that's probably a discussion best left for another day and another thread.
 
Ok but your question was about listed epa approved stoves. The link is a product for unlisted pre epa stoves
as a "professional" is your job to berate people asking questions about links posted on your own forum? I had no idea what that was. do you need perfect questions too?
 
as a "professional" is your job to berate people asking questions about links posted on your own forum? I had no idea what that was. do you need perfect questions too?
It isn't my forum. And I am in no way berating you here. I am one trying to figure out what you would be hoping to accomplish with the modifications you asked about so we may be able to help you get those improvements in other ways. And two trying to get you to realize modifying a listed appliance doesn't make sense
 
Mine does, but it still not as effective as it could be.

I argue the whole dwell time concept, it's about allowing the gas to touch the cold parts of the firebox to allow heat transfer. Industrial heat exchangers are designed to allow the working fluids to touch the most surface area in the least amount of time possible to increase total heat transfer.

But that's probably a discussion best left for another day and another thread.
Well yes getting hot gasses to contact more areas of the top is absolutely another reason for the deflectors. But they absolutely do slow the exhaust exiting the stove increasing dwell time as well. So yeah I completely agree with you but think my point was valid as well.

I have noticed the 2020 noncats have larger deflectors that are tighter to the baffles btw. That makes them more draft sensitive but increases efficency and slows the glasses more presumably giving the secondary combustion a little more time to work. I could be completely wrong there but it makes sense to me
 
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It isn't my forum. And I am in no way berating you here. I am one trying to figure out what you would be hoping to accomplish with the modifications you asked about so we may be able to help you get those improvements in other ways. And two trying to get you to realize modifying a listed appliance doesn't make sense
well, you a tough guy with a chip. and I would rather you just stay away with your bad self and not converse me. have a good weekend
 
The problem I see with intercepting a cat into the stove collar or smoke pipe area on an epa stove is light off temps and sustaining those temps, it would take a while to get the fire going to light off a cat, by the time the cat is lighting off the fire itself would be pulling air from the primary and secondary sources, eventually the fire in the box will keep rolling on itself and the designed secondary combustion would kick in, eating all the fuel leaving nothing for the cat located aft of the burn, making it useless.
 
There are incremental gains that can be achieved, but each little gain comes at greater and greater cost. As it is, our stoves can run with very little to no observable or uncombusted smoke after startup. Most particulates are released at startup. I suppose one could preheat the cat so it lightoff quicker, but I'm sure that would cause other issues as it is a designed system. Eventually, you'd end up with a pellet stove where the computer makes thousands of small corrections every second to ensure the greatest efficiency. There's a place for that, but there's also something to be said for simplicity.
 
well, you a tough guy with a chip. and I would rather you just stay away with your bad self and not converse me. have a good weekend
You didn't ask for my opinion but I care about the people here and it's the internet so I'm going to share it anyways:

I don't really understand why you're on these forums. I was browsing morning and happened upon 3 of your threads...all I see are well respected people with thousands of posts giving you advice, sharing their opinions, and you getting defensive when it's not what you want to hear. It was very cringeworthy to read. Nobody is berating or harassing you. What they are doing is challenging your opinions and I'd argue that's a good thing and should be welcome. Heating with wood is dangerous and needs to be done properly to ensure safety...which you are not doing. Why bother posting if you don't want to hear it?

I really hope you reconsider what you're doing but you do what you think is best. Good luck.