Not hot enuf.

[superiorsyrup]

We made our own arch recently using a wood furnace for fire box an extending our arch out the back. We have a 22" x 94" two flat divided pan set up. Our arch measurement between pan and arch behind firebox runs 6" to 1.75" in 69.5" and then out a 6" flue. Our stove and arch is insulated with 1" of durarock. We have auf in back of stove like many we have seen. Last night we did a test boil with water we can not get the back 1/2 of the pan to boil? Our flue gas in the 6 inch round averaged 200 deg. With a infra red Therm. If I measure starting behind firebox and check temp all the way to the end the temp drops from 350 deg to 125 deg.

So how do we get the flue end of arch hotter? What am I missing. I am going to add more auf as I am not exceeding flue capacity with air now do to a neck down from 6 to 1.5 inch on blower piping. Fire got hotter when I added air from leaf blower.

Thanks

[Cabin]

I just upgraded to a block arch but 6 inch flue seems rather small. How big is your fire box?? If my wood stove had such low stack temps it is starved for air. Are your numbers centigrade?

[superiorsyrup]

Fire box is 2x30" x 2'. Temps fahrenheit

[chad]

Fire box is 2x30" x 2'. Temps fahrenheit

what does that mean, and how long is your stack you want it at least twice as long as your pan/fire box

[Jeff E]

my old 2x4 had a 7" stack, and at one point I reduced it to 6", for a roof penetration. It had a noticeable negative effect on slowing the boil.
My old 2x8 had an 8" stack.
I would think you would want a 7 or 8 inch stack, with a height that is 1.5x the length of your pan.

Air under fire should be into the fire area, not just at the back. Also, wood quality makes a huge difference on your heat.

Bottom line, it sounds like you need to move more air through the arch, by directing more air at the wood, and opening up and maybe extending your flue.

[Cabin]

Fire box is 2x30" x 2'. Temps fahrenheit

I will assume the first 2 is in feet. That is a large firebox for 6 inch flue. How large was the flue opening before you modified it? You should be larger than the original I would think.

[superiorsyrup]

Original flue is 6". Our flue length is 25'. Right now I have air aimed below the grate in fire box. When I modify this afternoon I will aim air up higher. The fire was hot I had the fire box cherry red but still lacked on the flue temps.

Thanks

[Cabin]

Original flue is 6". Our flue length is 25'. Right now I have air aimed below the grate in fire box. When I modify this afternoon I will aim air up higher. The fire was hot I had the fire box cherry red but still lacked on the flue temps.

Thanks

I just do not understand the low stack temps. What does the 'smoke' look like??

[superiorsyrup]

Cabin.
We got it, not enough Auf. New 4" pipe on fan and boom we boiled average of 20 Gph and ran flew temps of 460 average upto 580. We kept it down just till we get more fire brick on the door.

[Cabin]

Cabin.
We got it, not enough Auf. New 4" pipe on fan and boom we boiled average of 20 Gph and ran flew temps of 460 average upto 580. We kept it down just till we get more fire brick on the door.

Keep an eye on the pipes! If you were running that cold you most likely have a lot of buildup in the flue. I did that earlier this season, when I got the heat right big chunks of black ash came raining out onto the roof(tarp).:o

[superiorsyrup]

Cabin, we couldn't let it run hotter for fear off warping the door or front of box to much. We could watch front of stove get red hot and warp, we need to firebrick it. What are your flue temps? That measurement is about 3' up flue above the arch.

[Cabin]

Cabin, we couldn't let it run hotter for fear off warping the door or front of box to much. We could watch front of stove get red hot and warp, we need to firebrick it. What are your flue temps? That measurement is about 3' up flue above the arch.

I go by how the 'smoke looks'. Clear heat waves are what I aim for and black smoke is to be avoided at all times. But them I am just one step above an open fire this year. Made a block arch with an 8 inch flue to hold 4 steam pans, aiming for a 2x4 pan once I get the bugs worked out. Since I heat the house and cabin with wood I now have a use for what is too big for the cabin cook stove and too small for the house stove.

[superiorsyrup]

Cabin,

I would say that is what we had. Clear no visible smoke at all just heat waves. Maybe smoke for 30 seconds at firing. I think we can get some hot flue temps when we get our door bricked. I kept the AUF down a bit to keep from wrecking anything. Not sure how much better we can get 20 gph on flat pans 2x6 (2x2 finish and 2x4 sap pan and a pre heater) We had a good gradient until the end of the second day (should have cleaned out the ash box). Our temps at pre heater were 100 deg!

Think we can get better with this set up?

[Cabin]

Think we can get better with this set up?

Isn't the effort to do better part of the game here???:) From the smallest producers to the largest we hear the same thing. 'Next year I will try/add this to get better.'