Thread #2 - Outdoor Stove

[Kustrud]

Alright, after much research and many....many trial sessions I am happy with what I found to be the safest way for what I wanted. What I wanted was essentially a Chimenea or a Metal Firepit sitting outside of our covered patio. But I also wanted the look of the wood stove and a way to direct the smoke/heat away from our house/deck.

If you saw my other thread, we just could not come up with an aesthetic way to use a Class A chimney pipe. So what I have done and decided on
is this:

1. I have gutted the interior of the stove, minus the fire brick. Basically a metal box with a completely open 6" flue.
2. I have used one piece of stove pipe with a 90 on top facing away from the house.
3. It burns great and drafts extremely well. Basically a chimenea that puts off some great heat but I am able to direct the output away from the deck.


This works EXCELLENT for our space and the smoke/embers are never anywhere close to anything. This would never be left unattended of course either.

My main wish here was to remove the glass and keep the "door closed" look but I do not need radiant heat....just the immediate frontal heat and ambiance. However, when I run the stove with the door open completely or the glass removed, I do get a fair amount of smoke coming out of the front
from time to time which is no good....

If I run it with the door cracked.....perfect! No smoke out the front at all....but would really love to remove the glass.

With how this drafts and everything inside (baffle board, baffle plate, etc. etc.) removed I figured 100% of the smoke would shoot straight up the pipe. Should I try welding a plate over the intake on the secondary air on each side under the stove? Could that be making a swirling effect inside the stove and pushing some out of the front?

Or would a "deeper" stove work better for what I am trying to do here? I just cannot see how if the door is open and the flue is open that smoke would make its way out the front.

In hindsight, I should have just bough an old-school stove and I would have had what I have now....but here we are lol!

Any ideas?

 

[bholler]

Alright, after much research and many....many trial sessions I am happy with what I found to be the safest way for what I wanted. What I wanted was essentially a Chimenea or a Metal Firepit sitting outside of our covered patio. But I also wanted the look of the wood stove and a way to direct the smoke/heat away from our house/deck.

If you saw my other thread, we just could not come up with an aesthetic way to use a Class A chimney pipe. So what I have done and decided on
is this:

1. I have gutted the interior of the stove, minus the fire brick. Basically a metal box with a completely open 6" flue.
2. I have used one piece of stove pipe with a 90 on top facing away from the house.
3. It burns great and drafts extremely well. Basically a chimenea that puts off some great heat but I am able to direct the output away from the deck.


This works EXCELLENT for our space and the smoke/embers are never anywhere close to anything. This would never be left unattended of course either.

My main wish here was to remove the glass and keep the "door closed" look but I do not need radiant heat....just the immediate frontal heat and ambiance. However, when I run the stove with the door open completely or the glass removed, I do get a fair amount of smoke coming out of the front
from time to time which is no good....

If I run it with the door cracked.....perfect! No smoke out the front at all....but would really love to remove the glass.

With how this drafts and everything inside (baffle board, baffle plate, etc. etc.) removed I figured 100% of the smoke would shoot straight up the pipe. Should I try welding a plate over the intake on the secondary air on each side under the stove? Could that be making a swirling effect inside the stove and pushing some out of the front?

Or would a "deeper" stove work better for what I am trying to do here? I just cannot see how if the door is open and the flue is open that smoke would make its way out the front.

In hindsight, I should have just bough an old-school stove and I would have had what I have now....but here we are lol!

Any ideas?

View attachment 325899

It needs more draft if you want to burn with the door open. That means more chimney because that is what creates draft.

 

[Kustrud]

Interesting, it seems like it's drafting really strong due to being unrestricted now....but I also cannot argue that what you're saying makes sense. I figured with the door opening as a main vent and an unrestricted box the short pipe wouldn't matter and that it would draft like crazy vs. stock EPA stove figuration.... It sure as heck is easy to start.....that's why I am kind of stumped!

Could the secondary intakes being open and letting air in above the fire (I'm referring to where the 4 burn tubes used to be under the upper baffle board) along with operating with the door open be hurting me at all here? Wouldn't be that hard to weld some steel in place over the inlets.

I could always run it like this with the door cracked, but would prefer without the glass if I can figure that out!

 

[stoveliker]

When the door is open, the secondary air is not sucking anything significant into the firebox. You need low pressure in the firebox for secondary air to be sucked in. With the door open there is not enough "vacuum" in the box. Especially with such a short pipe (which is the vacuum creator).

 

[Kustrud]

Makes sense, cracking the door vs. fully closing is giving me more vacuum thus creating the adequate draft on the short pipe...door cracked it is! I'll just have to play with it and see how far I can open the door before the smoke comes.

I noticed I can open the door towards the end of the fire when mostly coals and there is no smoke yet still a lot of heat for a while!

Is 700 degrees stove top temp OK for this use? Really nothing to "break" now except warping the box which I'd like to try and avoid if possible lol! That's about as hot as I could get it with the door cracked.

Hopefully this works for a while, I do have my eyes peeled for a large 2-door Fisher for this spot. Just need to find a deal, everyone wants $1,500 for them lol!

 

[bigealta]

Try removing the 90 elbow, or at least rotate its segments to make it 45 degrees.

Also u can add 1 or 2 2ft sections of pipe.

i have an old dutch west stove outside with 3 2 ft single wall pipes (6ft tall total) and it drafts fine with the doors open. No smoke out the door.

 

[brenndatomu]

The hole in can't be WAY bigger than the hole out...the hole out is 28.26 sq inches, so...

 

[Kustrud]

I need the 90 to blow it away from the deck/house and keep the rain out, and same reason I don’t want to make it 6 ft tall…..so it exits well below the height of the upper deck.

I’ll try adding 1-2 feet and see how it does with door open.

 

[Kustrud]

Would something g like this draft better than the 90 on the end of the pipe? Or does a 90 on the very end of a short pipe even hurt my draft at all?

 

[kborndale]

I need the 90 to blow it away from the deck/house and keep the rain out, and same reason I don’t want to make it 6 ft tall…..so it exits well below the height of the upper deck.

I’ll try adding 1-2 feet and see how it does with door open.

Two 45s= a 90

 

[Kustrud]

Two 45s= a 90

I know, I’m just thinking a 90 as an end piece can’t possibly effect draft as much as a 90 in a typical stove setup….I could be wrong though! 🤷‍♂️

 

[bholler]

I know, I’m just thinking a 90 as an end piece can’t possibly effect draft as much as a 90 in a typical stove setup….I could be wrong though! 🤷‍♂️

Of course it does

 

[EatenByLimestone]

The heat coming out your stove will dry out your deck really quick and cause the wood to check. Even if you 90 it out the back, that warm air going up will pull in other air that'll speed drying. I recommend doing it right or not doing it. Replacing part of that deck will be very expensive and the new part will never match the old deck.

 

[Kustrud]

The heat coming out your stove will dry out your deck really quick and cause the wood to check. Even if you 90 it out the back, that warm air going up will pull in other air that'll speed drying. I recommend doing it right or not doing it. Replacing part of that deck will be very expensive and the new part will never match the old deck.

The deck is brand new. I have also measured every single part of the deck around and above the stove after having a fire going for a couple of hours with an IR gun. The deck surface temp never got warmer than around 10-15 degrees vs the ambient temp.

People have brick fireplaces on/under wooden decks all the time, that would be just as close to any of the wood as this. Long as I can keep the heat/output away from the deck there’s really no difference.

Also, this will serve to have an outdoor fire when we entertain on weekends and it’s a cool evening….so a handful of times for a couple of hours per year.

Would you still be concerned??

I’d think the surface temp of any of these areas in the summer in GA will far exceed the temps I measured. The summer temps will be all day every day plus getting the wood over 100 degrees….

Curious on your response….

 

[EatenByLimestone]

A brick oven's outer surface will not get as hot as the stove's surface will. The thermal mass slows down the speed that the heat radiates out. For a few hours of burning, the skin of a masonry heater will only go up a few degrees at most.

The overall temperature of the deck isn't the issue. The entire deck being 100 or 120 in the summer doesn't matter that much. It's in equilibrium. The issue is a localized spot that has much lower moisture content. Say near your exhaust or over the 500+ degree stove. As the moisture level of wood changes the wood expands and contracts. It shrinks as it dries out. Right now, as you said, your deck is new. It's sopping wet and swollen. You dry out one little spot and that spot will shrink. Do it fast and the results are more extreme. Inside that board, its being torn apart. It sounds dramatic, but this is what the checking we see in firewood and boards is. This is what happens to all of the twisted 2x4s at Home Depot. Right now the moisture is telling the board to stay big, except for a little piece being told to shrink. There are ways to cut wood that minimizes these changes. Lumber isn't cut this way as its more wasteful in the processor's eyes. This normally isn't an issue, but its normally not speed dried in a small section.

The amount of times you burn it, the frequency, and intensity of the burnings makes a difference, of course. As said in your other thread, your house, do as you wish, but I don't believe its going to end well for your deck unless you handle the exhaust correctly.

 

[bigealta]

How about put the stove on wheels. Roll it under the deck when it rains. Roll it out to the edge of the pavers when burning.

A $13 dolly from HF could do the trick.

 

[Kustrud]

A brick oven's outer surface will not get as hot as the stove's surface will. The thermal mass slows down the speed that the heat radiates out. For a few hours of burning, the skin of a masonry heater will only go up a few degrees at most.

The overall temperature of the deck isn't the issue. The entire deck being 100 or 120 in the summer doesn't matter that much. It's in equilibrium. The issue is a localized spot that has much lower moisture content. Say near your exhaust or over the 500+ degree stove. As the moisture level of wood changes the wood expands and contracts. It shrinks as it dries out. Right now, as you said, your deck is new. It's sopping wet and swollen. You dry out one little spot and that spot will shrink. Do it fast and the results are more extreme. Inside that board, its being torn apart. It sounds dramatic, but this is what the checking we see in firewood and boards is. This is what happens to all of the twisted 2x4s at Home Depot. Right now the moisture is telling the board to stay big, except for a little piece being told to shrink. There are ways to cut wood that minimizes these changes. Lumber isn't cut this way as its more wasteful in the processor's eyes. This normally isn't an issue, but its normally not speed dried in a small section.

The amount of times you burn it, the frequency, and intensity of the burnings makes a difference, of course. As said in your other thread, your house, do as you wish, but I don't believe its going to end well for your deck unless you handle the exhaust correctly.

Good explanation, and I do agree with you on the science behind it. We spent a lot of money on the deck and obviously do not want to damage anything. I do firmly believe that the exhaust as well as the body of the stove is far enough away from any wood to really heat it up much, if any at all honestly.

I would not use the stove on a windy day either, which is the same for my fire pit.

I think I'll go with either 3 or 4 feet of pipe with a 90 on the end so it's facing directly away.

I had an idea too. Given that it works great with the door cracked about 2 inches or less, I am going to replace the glass with a sheet of this. I'm hoping this should technically "lessen" the size of the intake (open door) thus creating more vacuum than just an open door/missing glass along with giving the viewing ambiance as well as direct frontal heat.

 

[Kustrud]

How about put the stove on wheels. Roll it under the deck when it rains. Roll it out to the edge of the pavers when burning.

A $13 dolly from HF could do the trick.

Not a bad idea!

 

[Kustrud]

I do appreciate all of the input, concerns, and interest on this! Close to having a final and safe solution I hope!

 

[Kustrud]

Ok, found a scrap to try.

It works PERFECT!

Door open, smoke. Close door with screen, no smoke!

I need to order a piece now so I can cut it out exactly the shape as the window!

 

[Kustrud]

Finally got the new piece cut and installed. Works and looks perfect! No smoke at all out the front!!

Also, the stove quickly had some rust after the first rain. Sprayed it with canola oil pretty heavy and rubbed it down and then had a fire. It’s rained 3 times since then and it has a nice protective sheen and no more rust!

 

[30WCF]

Looks like when I’m trying to watch my food cook in the microwave.

Hope it works out for you.

 

[Kustrud]

Crazy how this stops any smoke coming out the front!

 

[30WCF]

They do sell screens you can use for wood stoves if you want to leave the door open in a normal set up I suppose. Not real sure if folks use them in their houses.

 

[Kustrud]

They do sell screens you can use for wood stoves if you want to leave the door open in a normal set up I suppose. Not real sure if folks use them in their houses.

View attachment 326347

Yeah I thought about that too. I like the look with the door closed, but yet can still hear and feel the fire! This worked out well!