Refractory modification/addition on Greenfire

[sparke]

I added a piece of refractory to the top of the fire box. I am impressed with the increase in performance. This fire was from yesterday. I was charging my tank. About 75* outside burning oak cut last Sept. When I took these pictures I had to stand 3 feet back the heat was so intense. Picture quality not great - cell phone camera... When I told Mark from Greenfire my idea to do this, he had already done it and liked it. I may add a few more pieces of refractory on the top sides.


This piece of refractory was made with a plywood form , about 25# of castable refractory, and stainless steel needles for strength.

If you look closely you can see blue flame going over the top in the second and third picture. In the last picture you cant see it all but the fire was mostly blue. I love blue fire!!

The time it takes for 0 visible smoke is about 10 to 15 minutes after reload.

 

[sparke]

This is a piece made by Mark from Greenfire. As you can see his piece is about 5 to 6 times the mass of mine. I am sure it works better but I did not want to loose the space down into the firebox. It is only a few inches but it would affect rolling in 12 and 13" logs. They would get jammed. Keep in mind I have the smallest unit. This size might not affect the bigger units. You would need to take the top maybe the side off to install this one. I put mine in through the door.

 

[ISeeDeadBTUs]

Beacause I am not an engineer, nor - if you read the newspaper - am I terribly bright, can you walk me through why you thought this would be beneficial?

 

[sparke]

I am not an engineer either abut I like Heineken so I will give it a shot.

1. I figured the heat rays being reflected down into the fire would help accelerate the burn.

2. If you ever watch your fire burn you will notice the gases and unburned smoke (if any) head right towards the back of the unit, thus bypassing a large part of the hex. Obviously the gases are going to travel the shortest distance to the exit point/draft origin. I wanted to make the gases travel across the whole hex. This simple design change seems to accomplish that.

Cheers!

 

[slowzuki]

In general lengthening the hot path the combustion gases take increases the completion of combustion. You have to be careful reflecting too much heat back in because it may gasify the wood too quickly for how much air is admitted.

 

[sparke]

Slowzuki, What is an indication of that happening? (too much gasification) Do you think it can create a hazard?

 

[antknee2]

Hi Sparkey
Very cool invention , you would not believe the size of the gap on the Seton boiler , check out the video .
Anthony

http://www.youtube.com/watch?v=WCbB2nSU82Y

 

[SteveJ]

Anthony,

I agree about the gap at the back of the Seton.

Lots of smoke from a cold start!!

Like the video - also like your endless pool video...

Are you going to fill the gap on your Seton?

Has anyone talked to Fred about the gap?

Steve

 

[sparke]

Something I never noticed before. The Seton refractory seems to go all the way up to the Hx. Mine stops short of the Hx. As you can see that gave me a place to set the top piece. It does not appear that you would have a place to set the top piece. The biggest goal was to change the travel path of the gases to flow over the front of the Hx. I don't think plugging the back hole will accomplish that for you.

BTW, Nice Video on the Seton.

 

[Norman]

Beacause I am not an engineer, nor - if you read the newspaper - am I terribly bright, can you walk me through why you thought this would be beneficial?

I have a question for you... WHo are you ??????

 

[ISeeDeadBTUs]

I have a question for you... WHo are you ??????

Why?

 

[Norman]

you crack me up with your remarks...

 

[ISeeDeadBTUs]

there are those that would tell you I'm on crack . . . as with most rumours, though . . .

 

[Norman]

you are not Phil Doherty are you???!! Ha

 

[Norman]

looks great nice clean refractory

 

[Norman]

Beacause I am not an engineer, nor - if you read the newspaper - am I terribly bright, can you walk me through why you thought this would be beneficial?

When I tested the Adobe I had used a Vermiculite board as a baffle and it increased the burn efficiency but not the heat tranfer efficiency. My personal opinion would be that if refractory could be cast ABOVE the pressure vessel to reflect the heat back thru the vessel this would be a win win. THis would give u great heat tranfer and better more intense gasification..

 

[antknee2]

Beacause I am not an engineer, nor - if you read the newspaper - am I terribly bright, can you walk me through why you thought this would be beneficial?

When I tested the Adobe I had used a Vermiculite board as a baffle and it increased the burn efficiency but not the heat tranfer efficiency. My personal opinion would be that if refractory could be cast ABOVE the pressure vessel to reflect the heat back thru the vessel this would be a win win. THis would give u great heat tranfer and better more intense gasification..

Wow Norman that sounds like a great idea . Also would make it easier to brush off the top HX tubes without snagging the mineral wool insulation . Thanks Anthony .

 

[antknee2]

Anthony,

I agree about the gap at the back of the Seton.

Lots of smoke from a cold start!!

Like the video - also like your endless pool video...

Are you going to fill the gap on your Seton?

Has anyone talked to Fred about the gap?

Steve

Hi Steve
To be honest with you I feel the boiler is producing a enormous Btu output when I burn seasoned hard wood and running with clean HX tubes . But definitely something consider . Thanks Anthony

 

[Norman]

Beacause I am not an engineer, nor - if you read the newspaper - am I terribly bright, can you walk me through why you thought this would be beneficial?

When I tested the Adobe I had used a Vermiculite board as a baffle and it increased the burn efficiency but not the heat tranfer efficiency. My personal opinion would be that if refractory could be cast ABOVE the pressure vessel to reflect the heat back thru the vessel this would be a win win. THis would give u great heat tranfer and better more intense gasification..

Wow Norman that sounds like a great idea . Also would make it easier to brush off the top HX tubes without snagging the mineral wool insulation . Thanks Anthony .

I have pictures somehweres of how I had done it. I will look

 

[Willman]

Anthony
Doesn't the Seton have a forward facing flare cast into the top of the rear wall ? Does the insulation blanket actually touch the fire ?
Will

 

[antknee2]

Anthony
Doesn't the Seton have a forward facing flare cast into the top of the rear wall ? Does the insulation blanket actually touch the fire ?
Will

Hi Willman
Your right about flare out on top casting . The fire actually blasts the blanket of insulation and the insulation stays white , if you burn hot and damper open for for two three hours at a time . Crazy system , but it works .

 

[Willman]

Anthony
I couldn't figure out how the insulation worked exposed to fire. Glad to hear it works. The top flare must help direct the heat flow forward to contact the HX sooner. It seems from the pics of the Greenfire I have seen that their HX tubes don't project as far forward as the Seton. I have interest in your posts and setup due to the fact I am considering building a Seton. Thanks for the info.
Will

 

[antknee2]

Anthony
I couldn't figure out how the insulation worked exposed to fire. Glad to hear it works. The top flare must help direct the heat flow forward to contact the HX sooner. It seems from the pics of the Greenfire I have seen that their HX tubes don't project as far forward as the Seton. I have interest in your posts and setup due to the fact I am considering building a Seton. Thanks for the info.
Will

I have some real good news , the new Setons will have side access panels , built in from day one for cleaning the hidden parts of the boiler . Anthony

 

[roaring fire]

refractory on top of the water vessel. I agree with Anthony it might improve efficiency &
assist cleaning those horizontal pipes. Has anyone tested this ? Maybe Greenwood or Seton
would conduct this experiment for their dedicated clientele.
Where can one access refractory material?