PE Super 27 retrofited with catalytic combustor

[10bushmich10]

So here is the story. I owned a blaze king princess in the past but ended up selling it because I installed extremely efficient Fujitsu heat pumps and thought I'd not use wood any more...... It's like heroin (I'm not a user) once you burned wood u can't stop. So I purchased a abused pe super 27 with a burnt through baffle and deformed side rails. Little torch heat and love with welding and I re fabbed the metal guts of the super 27 wood stove. New gaskets and the thing was a rocket. Load her up with 2-3 year dried under roof fore wood, get it to 400f and turn it down all the way with a flue damper and she would run at 700f for a good 4hrs then coals up to 6hrs. Way too much heat for my 1300sqft home. 600 down and 700upstairs.

Then came the ideas of how I could slow the burn and keep it clean. I had a rotten combustor from the blaze king laying around so fabbed up a 3/16 box with a 4"x8" bypass opening in the back. Essentially it's designed like the blaze king layout except it's bolted to the top of the stove for easy removal Incase it warped or I didn't like it's operation. The secondary air inlet in the back was plugged with roxul insulation so only the front air wash is my air control which I set to 1/2inch from closed for a 450-500f stove top. Window stays allot more clear than my blaze king did. I think thats got something to do with how deep the stove is. I'll show pictures of its construction later.

So far im pleased. The only thing I miss is a bit metallic thermostat which I need to Fab up for a more linear heat out put like the royal blaze king. So far this last load of from 20-30lbs of wood in it and I loaded it at 9pm yesterday and it's 1240pm now and I can get another 2hrs out of it before reload. Stove top is 400 and cat is 600f. The condar combustor thermometer is like one inch from the combustor instead of the required 1/4 inch. Also it's way off. I pulled it out when it was reading 350f and I put in my wifes digital cooking thermometer and it went to 500f and maxed out so it was above that.

So the pics are as follows: from first to last. Loaded at 9pm, 730am,1230pm with stove top pics. Then a catalytic picture when it's first going. Then a intro pic of how the cat box is constructed. I did buy a new cat from Amazon.

 

[10bushmich10]

16rs into the burn and all I got is ice on my chimney and stove top of 350f and flue in the 150s. I could Easley get 450f if I turned up the air but it's on low and still feeding the cat with enough fuel. The outside temps have been in the 20s with wind since I loaded the stove. House is at 75f. The cat thermometer is off by at least 200f confirmed with a digital cooking thermometer.

 

[ckr74]

Interesting. I always wondered if anyone had tried this. I might think about doing this to my 30nc in the future. Too bad someone hasn't come up with a kit of some sort to do the conversion.

 

[moresnow]

The mother of all stove mods. Must be running like my BK according to your cap.

Get some detailed pics of your cat assembly when you finally can whoa the beast! Likely not PE approved but very interesting.

 

[Highbeam]

Totally cool but totally illegal. Tampering with a federal required emissions device if you worry about that sort of thing.

 

[10bushmich10]

Interesting. I always wondered if anyone had tried this. I might think about doing this to my 30nc in the future. Too bad someone hasn't come up with a kit of some sort to do the conversion.

Honestly is extremely easy to get done. Draw up some drawings of a steel box the size the combustor you want to use (I think that the blaze king princess combustor is best due to it's size and dimensions. Some combustors are long-thing-short; basically suck so blaze king did a good job with theirs). The box must have enough room in the front door a 4"x8" damper opening which is the avg sq inch that an 6inch flue has. I get no smoke rolling into the home when I open bypass and front door. Now go to a metal shop that has steel and they will cut up all your sizes to a 1/8 inch accuracy. Next weld it up or take it to a weld shop. All together it cost me like 100$ for the steel all cut up (I went with 3/16" but suggest 1/4" for less chance of warping). Then I welded it my self.

So Lincoln says you need like a 170amp mig welder to weld 1/4 steel. If you use mig wire with a flux core (instead of gas) it burns allot hotter so it welds thicker metal. I used a 120amp might welder with .35 flux core wire and it would burn through the metal if I turned it upper all the way(pretty sure it could weld 1/4" no prob). So a avg welder could rig this up for you for maybe another 100$.

Then the combustor is 186$ from Amazon or 300$ if you want a "reputable brand" or steel. As for the by pass I had some thought into that. There is no gasket Which was a concern for me but it lays down flat and I see no smoke from the chimney. The bypass plate probably is 5"x9" so half inch bigger then the opening. I suggest one use 3/8" plate for the bypass due to it being heavier and laying down flatter but if one wonders my 3/16 has not warped but I don't need to rip the stove on hi for 45min on a reload. Maybe 1 min with open bypass then 10min of medium air setting before slamming the air all the way shut. By this time the wood is charred all over and the bottom pieces are getting red I have wood that is like 8-10% been drying in my green house since the fall and a year under a deck before that.

Now how do you get it in your stove? Well make sure what your building will fit in your door..... To the side of the box I welded 4 3/4" nuts and I drilled holes in the top of my stove and bolted up the box. The back of the box ends at the edge of the flue collar.

How about the by pass handle eh? That one got me thinking..... I didn't do the blaze king set up because it's got to many moving parts and i don't got time for that. So I welded a 3/8" inch wrench extension from harbor Freight a black one not one that's chrome. Its welded to the plate and protrudes just outside of the box. Next when I bolted the box up to the stove I marked where the bypass plate rod would exit the stove and took the box out and drilled my hole through the stove. Make sure you drill a smaller hole so you don't have air leaking. Make it to big and your screwed, if it's to small you can make it bigger later. Bolt the box back up. So next I put another 3/8" extension from the outside into the one that just protrudes from the combustor box. It clicked in. Now for handle use a breaker bar or what you like. The one issue with this getting if to stay open for reloading the stove. If it doesn't then hang a small weight on the end of the handle when you open the bypass.

Another concern I had was air leaking around the box where it's bolted but when I ran if for a bit and took it down the edges where clean. No black soot so it's tight up against the top. I'll try to do a video when the stove is out and explain it in more detail.

 

[10bushmich10]

Totally cool but totally illegal. Tampering with a federal required emissions device if you worry about that sort of thing.

I had thought of this but how i got the stove it wasn't epa anything at that point. I was a burnt out box that probably would smoke like a old dragon. Epa should award me for making the stove better. Lol.

 

[10bushmich10]

The mother of all stove mods. Must be running like my BK according to your cap.

Get some detailed pics of your cat assembly when you finally can whoa the beast! Likely not PE approved but very interesting.

Wish it ran as low as the BK. Last night I loaded the stove full( PE is 2.1cbft and this box sits maybe 1/2" lower then the original baffle plate so stove is now probably 2cbft.). Think I put 20ish lbs of wood in. I'll try to weigh it next time. Let her rip for ten min and turned it down all the way. No fire, just a red cat from 9pm to around 3am with stove top of 500f. In the morning at 7am I had a 330f stove top and active cat so I turned it up a 1/4" more and now it's been at 400f and has enough to go till one or two PM for a 300f stove top reload.

I have plans to try to set up a bi-metalic thermostat so it could run at 300f stove top. I'm very happy with how it runs. I get 16+ hrs of a steady warm house that doesn't over heat and I use less wood and re load allot less. This is with tems in the middle teens at night and low 20s today. Maybe when it's in the 30s or 40s the lowest air setting will naturally draft less and run a lower stove top.

 

[mellow]

How things go in a full circle. Retro kits have been around for a long time. The question is if your house burns down due to a modified wood stove will your home insurance cover you?

Back in 2006: https://www.hearth.com/talk/threads...ro-fit-kit-for-older-buck-stove-inserts.3600/

 

[10bushmich10]

Back in 2006: https://www.hearth.com/talk/threads...ro-fit-kit-for-older-buck-stove-inserts.3600/[/QUOTE]

How things go in a full circle. Retro kits have been around for a long time. The question is if your house burns down due to a modified wood stove will your home insurance cover you?

Back in 2006: https://www.hearth.com/talk/threads...ro-fit-kit-for-older-buck-stove-inserts.3600/

The only thing I can answer to that is that I don't live by and am not motivated by fear but by commen sense and good proven practices. If one sits down and thinks about what it would take to have a house fire from a stove you would realize one has to do something foolish to get that to happen like run old non EPA stove beat red at 1200f half a foot from his wood pile. What I did is make the the stove run a half of it's reg temperature but for twice as long. No fear of a house fire. Cleaning your chimney is req with any stove. Hope I don't sound rude and I'm not trying to beat the last poster over his head. We all make our own life choices and approve or disapprove them relative to how we we're brain washed by our family/childhood.

 

[bholler]

Back in 2006: https://www.hearth.com/talk/threads...ro-fit-kit-for-older-buck-stove-inserts.3600/

The only thing I can answer to that is that I don't live by and am not motivated by fear but by commen sense and good proven practices. If one sits down and thinks about what it would take to have a house fire from a stove you would realize one has to do something foolish to get that to happen like run old non EPA stove beat red at 1200f half a foot from his wood pile. What I did is make the the stove run a half of it's reg temperature but for twice as long. No fear of a house fire. Cleaning your chimney is req with any stove. Hope I don't sound rude and I'm not trying to beat the last poster over his head. We all make our own life choices and approve or disapprove them relative to how we we're brain washed by our family/childhood.[/QUOTE]
What typically causes a house fire is either imoroper instalation or chimney fires. Your exhaust temps are really low and have the potential to create tons of creosote cat or not. That puts you at serious risk of a chimney fire on startup with the bypass open. Just because your stove runs at low temps does not at all mean there is no risk.

 

[Diabel]

I like the ingenuity. But sorry to say.....you are running an illegal appllince in your house that voids the house warranty.

 

[jetsam]

I like the ingenuity. But sorry to say.....you are running an illegal appllince in your house that voids the house warranty.

Man, I wish MY house had a warranty.

 

[Diabel]

Bad English I know.

I am in TCI enjoying few too many cold ones....

You all know what it meant.....

 

[begreen]

Very cool modification. How much lower does the cat/bypass assembly sit as compared to the original baffle location. It looks 2-3 inches lower, but that's hard to tell from one picture.

 

[Sailrmike]

Back in 2006: https://www.hearth.com/talk/threads...ro-fit-kit-for-older-buck-stove-inserts.3600/

The only thing I can answer to that is that I don't live by and am not motivated by fear but by commen sense and good proven practices. If one sits down and thinks about what it would take to have a house fire from a stove you would realize one has to do something foolish to get that to happen like run old non EPA stove beat red at 1200f half a foot from his wood pile. What I did is make the the stove run a half of it's reg temperature but for twice as long. No fear of a house fire. Cleaning your chimney is req with any stove. Hope I don't sound rude and I'm not trying to beat the last poster over his head. We all make our own life choices and approve or disapprove them relative to how we we're brain washed by our family/childhood.[/QUOTE]Never mind the UL listing. Doesn't matter how the house fire even starts, they are devastating. Your insurance company will not cover your financial losses with that setup. People in my own town had a house fire, it was "blamed" on the wood stove, no building permit was issued for the stove.... The insurance company didn't give them a nickel. Just saying, none of us here want you to go through that

 

[10bushmich10]

Very cool modification. How much lower does the cat/bypass assembly sit as compared to the original baffle location. It looks 2-3 inches lower, but that's hard to tell from one picture.

So the cat box sits approximately half a inch lower then the original pe secondary baffle so I didn't really loose anything. I load the wood right up to the top of the cat box and if I have a skinny piece I can fit it up next to the side of the cat box (few extra pounds of wood, those who own a blaze king princess know what I mean).

I think in most stoves this cat box would not loose more than an inch of loading height because these new epa stoves have the secondary system which if you remove all together probably takes up 3-4inches of room from your top plate. The blaze king combustor (which I think is best due to it's perfect size.... Not too long or thin or too wide like some other brands) is like 10.6inches by 4inches tall by 2inches deep. So you can count on loosing 5 inches from the top of your stove after adding in the thickness of the metal under the combustor.

You may loose an inch or two but your stove can run allot longer........

 

[10bushmich10]

The only thing I can answer to that is that I don't live by and am not motivated by fear but by commen sense and good proven practices. If one sits down and thinks about what it would take to have a house fire from a stove you would realize one has to do something foolish to get that to happen like run old non EPA stove beat red at 1200f half a foot from his wood pile. What I did is make the the stove run a half of it's reg temperature but for twice as long. No fear of a house fire. Cleaning your chimney is req with any stove. Hope I don't sound rude and I'm not trying to beat the last poster over his head. We all make our own life choices and approve or disapprove them relative to how we we're brain washed by our family/childhood.

Never mind the UL listing. Doesn't matter how the house fire even starts, they are devastating. Your insurance company will not cover your financial losses with that setup. People in my own town had a house fire, it was "blamed" on the wood stove, no building permit was issued for the stove.... The insurance company didn't give them a nickel. Just saying, none of us here want you to go through that[/QUOTE]


I thought this through too. So my thought on this was.... all these cars and trucks have so many mods to them, bigger tires or lift kits or what ever they do which was never tested and approved for that specific vehicle by what ever organization approves cars road Worthy and safe for operation..... When those cars get in a accident the insurance pays out no questions asked. Even though I'm pretty sure they could also say hey, you didn't drive your car with factory specs equipment so you were not able to stop in time so it's your fault. Or, you rolled your truck because you lifted it... No they just pay out. So if any one has a house fire and I hope nobody does, just make sure you get a lawyer if your insurance company is trying to screw you by saying it was the stoves fault or what ever else they come up with.

 

[10bushmich10]

The only thing I can say to those who are afraid of the low exhaust temps one should watch the blaze king video on YouTube. They have a cut out like 3 inches from the top of the stove and the speaker puts his hand in the cut out to show how little heat is coming out of the stove. A catalyst in a stove is just about at different as a electric car is from a gas one... Both have 4 wheels and get from point a to point b but do it very much different. Electric is quiet and very efficient and almost no losses in waist energy where as a gas engine has a radiator to blow off the waist "heat energy" that is produced by gas engine. Ain't got no radiator on a electric car. Family is in the car business and hybrid business.

So back to catalytic stove. What you get is a stove within a stove. The catalytic combustor box works as the primary heating device at low-slow burns. It is burning 95% of what passed through it at a very very slow air flow rate. That's why your chimney temp is low. When you need more heat and turn up the air the wood actually begins to burn giving you extra heat and the catalytic burns off the rest producing more clean heat.

If one is interested they can read through the posts of blaze king owners who clean their chimney. There is not much to clean at all.

 

[mellow]

All of us are familiar with cat stoves and how they work, I have had many different ones through the years including Blaze King. I went through the same phase you are going though and modified my stoves to burn slower and lower as well. I however would only recommend it for somewhere else other than your primary dwelling if you want to tinker with retrofitting stuff in a stove that is not designed for it, after a close call I woke up to the fact I would not be covered if the house burned down due to a modified stove and have since bought new stoves.

Not trying to stifle your ingenuity of something that has been done before for many years but really should it be taken out to the garage, especially with kids in the house.

 

[begreen]

So the cat box sits approximately half a inch lower then the original pe secondary baffle so I didn't really loose anything. I load the wood right up to the top of the cat box and if I have a skinny piece I can fit it up next to the side of the cat box (few extra pounds of wood, those who own a blaze king princess know what I mean).

I think in most stoves this cat box would not loose more than an inch of loading height because these new epa stoves have the secondary system which if you remove all together probably takes up 3-4inches of room from your top plate. The blaze king combustor (which I think is best due to it's perfect size.... Not too long or thin or too wide like some other brands) is like 10.6inches by 4inches tall by 2inches deep. So you can count on loosing 5 inches from the top of your stove after adding in the thickness of the metal under the combustor.

You may loose an inch or two but your stove can run allot longer........

I'd only do this if a) I had a beater stove and 2) I had a welder and knew how to use it as well as you do. I have neither and our PE stove is functioning well, so I will pass. 12 hr burn time works fine for us. Someone is usually home these days. But I do respect your can-do attitude and the nice conversion.