Adding a Cat to a smoke dragon

[mellow]

Ok Guys, need some advise on if this project is worth doing or not. I will put in the pics as I go along to help. I am wanting to add a cat to my old craft stove to try and help make it a little more efficient, I have bought an old cat and want to cut my damper and install it so when I close down the damper the cat will hopefully work. My craft stove isnt a top venting stove so I know I will loose some of the effect right there but I am hoping it will help cut down on my wood usage. My plan is to cut out the damper just enough to be able to put this cat in the hole and attach it to the damper via the to screw mounts on the side.

Do you guys think this is possible?


Pic of stove in general:

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Wide shot of Damper:

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Pic of Damper closed:

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Pic of my Damper open:

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Pic of Cat held up to damper:

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Pic of Cat:

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[Todd]

Unless you can put that cat above your damper and protect it somehow from flame impingement it wont last long. Maybe some kind of baffle with the cat in the front of the stove and the damper in back would work better?

 

[mellow]

I am trying to copy the nu-tec design, they leave theirs open to the flame. As I found out servicesales no longer carries these, or anyone else.

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[RedRanger]

My honest opinion is that I think it is an exercise in futility. I recently sold my (1985) pe insert. And in the manual, it stated that the cat was an option. Maybe at one time it was, but when I went to the factory to inquire about that aspect. The people there had a difficult time even bringing up the schematics for my baffle. Which, much to their credit, they did manage to do.

So, just saying, that even though, many,many years ago, my old beast was designed to have the cat as an option. Problem is parts are no longer made for that option.

Think that all you are gonna wind up doing is "frying the cat" very quickly -- tail and all!! :smirk:

Or, you might just get lucky?

 

[brooktrout]

I have been wanting to do some type of mod to my insert to acheive higher efficiency, as well. I haven't gotten too much input. Wish there were more threads on this, retrofitting older stoves. Good luck, let us know how it turns out.

 

[jpl1nh]

I would imagine you could probably make the cat so it could fire off but it seems unlikely to me that it will accomplish your goal. Inserting a cat in the pipe will reduce the particulate output but won't really increase your efficiency. Cat stoves capture the heat from the catalytic combustion and release it to the stove body and then the room. Having that combustion occur in your stack will make it unlikely that cat combustion heat will make it into your room ,more likely just up the chimney. That's my theory anyway. If you go through with it, let us know how it does.

 

[karl]

Give it a shot. I'm not sure you'll get alot more heat but you will clean up your exhaust. And you may be able to close the air down more and get longer burns. Also, less chimeny cleaning.

I need to get my homemade CNC machine done, So I can hook my plasma cutter to it, and make a 6 cubic foot PE Summit copy.

 

[mellow]

Does anyone see any safety issues with doing this? My main concern is how will it affect my draft, I just insulated my liner to fix the back puffing problem I had last year, this year it has been drafting alot better with the external chimney.

 

[Todd]

There are always safety concerns when you modify a stove to perform differently than it was tested. If I was doing this I'd probably haul it out in the yard, stick a few lengths of stove pipe to it and test it out there where there is no danger of burning the house down.

 

[pistonslap]

I have an old non cat furnace that was eating a lot of wood and not giving me the amount of heat I should have been getting. What I did was make a baffle out of sheet metal in the shape of a c-channel with tabs on the ends to screw it to the back of the stove. My stove pipe comes out the rear of the firebox and even with a stovepipe damper closed my chimey temps would get really high just as the furnace was building heat. My airbox is above the fire box with a thermostat for the blower and my fan would run a 2 min. on 5-6 min. off cycle that never really delivered the amount of heat it should have. After putting my giant brain to work I figured that with all my heat going up the chimney it wasn't staying in the firebox long enough to keep the airbox hot. The 10" long x 8" wide x 2" rise baffle completely covers the flue. The 2" rise allows the the smoke to go around the sides of the baffle and up the chimney while keeping the flame from going directly up the flue. My furnace is free standing with plenty of clearance so I never really have to worry about the stovetop temp. But to be honest, with that baffle in I'm building a lot more heat with a lot less fire. Also the bed of coals throws heat thru my duct work for at least a good hour before I have to reload. My burntimes have gone from 1 1/2- 2 hours to 3 1/2- 4 hours. One more thing, since I was restricting my exhaust gases, I installed a carbon monoxide detector 8-10' away. My stove pipe damper is all the way open all the time now and my chimney temps are in the safe range. I used to read about people saying their stove was cruising. I was always throttling up or backing down. Now once you get it to a nice bed of coals it cruises. What a wonderful feeling!