Two stoves, same conditions, different problems

[cottonwoodsteve]

If you have problems people criticize your installation, wood or operating methods.
I had problems so I did experiments, since I wasn’t getting helpful information.
A great plus point is I have two systems to do A/B comparisons.
WOOD STOVE in den. INSERT in fireplace in living room. Both installed within the last year. All done to code and manufactures specs. Both in single level house. Fairly open floor plane between the two rooms. Never operated at same time.
Average temperature at evening start, 55 F inside, 45 F outside.
No wind or rain. Black print newspaper, commercial bundle of thin pine kindling.
Tests done with Ecco logs or Presto Logs. All stored inside.
Basically it just doesn’t get any better as far as perfect and repeatable conditions.
INSERT has shallow box and bay window door. Fire is forward toward large bay window door. This sounds like it could be a problem but even starting cold it doesn’t smoke with the door all the way open. Starts easily. But relative to it’s size doesn’t put out much heat. Air wash keeps windows fairly clean
The WOOD STOVE is deep. The fire can be far back and the door is small. This has a constant smoking problem. You can’t open the door more than a few inches. Hard to start. Air wash does nothing to keep window clean
Sometimes it appears to have a blocked pipe. Intermittently even with a flash newspaper and kindling it starts going out and opening the door slightly only lets smoke out and no air goes in to perk up the fire. But if it ever does get going, it puts out three times the heat for same amount of wood, compared to the INSERT.
Same house, same level, same newspaper, same kindling, same test wood (presto logs), same operator, same weather and temperature.
The wood stove has a smoking problem, but also intermittently appears to get blocked completely. But here is the real fun part. The intermittent problem appears occasionally on week days only. Never on weekends. Since it is all the same and darn near perfect, people can’t say problems are related to; my installation, wood or operating method. It’s all the same and yet two different EPA approved devices operate with greatly different plusses and minuses.
Now let’s see people make statements as to what the problems are. The purest say there is nothing wrong with these new designs. But the fact is two different devices act greatly different under the exact same conditions. I will grade your answers in a few days. GO!

 

[shawneyboy]

Could one of the differences be an inside versus an outside chimney/flue? Or could the difference be different caps? Could the difference be different or wrong diameter flues for the specific appliance? Could it be the length of the flues? Could it be the downdraft from different sides of the roof slope? Could it be ...... Still many questions that could be causing a difference.....

Shawn

 

[remkel]

The first question that came to mind for me is one shawneyboy mentioned- that being different sides of the roof. Coould possibly be that one chimney is getting a completely diffferent draft effect from the predominant wind direction in your area.

All the other questions are very valid also. Additional question to consider- appliances that may be running (clothes dryer etc) that may have an effect on your draft. The problem is, this whole wood burning stuff is never a completely controlled environment (from a scientific perspective) for there is always something changing each time you place a match to the kindling. All you can do is make certain everything is connected correctly then it is a matter of trial and error.

As an example, I get a terrible downdraft on my flue when the stove is not running. My suspicion is there is one room in my house that is not insulated as well as the others and the flue is actually becoming my make-up air in the house. When the fire is lit, I can feel the draft coming through the house in the other direction.

Good luck.

 

[Backwoods Savage]

Steve, congratulations for experimenting because that is always a good thing to do....within reason. In your case though, I would expect different results simply because they are two different stoves. However, your problem seems to be lack of good draft and lots of smoke.

The only difference you did not mention concerning weather is barometric conditions and time of day. No wind is great for experiments because wind can be quite fickle. As for the barometer, that can indeed be a big factor in how a fire burns. As the barometer is lowering, the fire tends to be a bit more slow. As it is raising the stove tends to burn better.

Draft problems and especially a smokey stoves usually go together like hens and eggs. I don't know what your chimney situation is so can not comment too much on that except to say if the two stoves have different types of chimney, then there can be a huge difference. As you know, height can be a big factor as can be size. SS vs. block can give a big difference.

Wood, now we can talk some big differences. For sure you can not burn the same wood in two stoves. You can burn similar wood but not the very same pieces. Does or can that make a difference? Absolutely! I'll give you an example: Last winter we burned wood that was from 6-8 years in the stack. That is, 6-8 years total time stacked since being split. The wood was a mix of ash, soft maple, elm and a spattering of cherry. Perhaps 80% was ash. I'll use ash for the comparison because the others often give wide variances in burning characteristics.

The ash has a bit of a theory for lots of people. Even a man who I recently sold some wood commented to me how good that ash burns. He was amazed, but still, many folks he had talked to had told him ash could be cut, split and burned in the same day. Well, that is true.....somewhat. When I told him about how we stack the wood and let it dry and how it is different, he was totally amazed. For example, we stack our wood 4' high....almost. Actually we stack it about 4.5' high and it shrinks as it dries. The wood he received was stacked at 4.5' high but the pile was less than 4' high when we threw it on the trailer. That is how much it had shrank. What causes this shrinkage? For sure, you know the answer to that one.

So how does our ash burn? Excellently....most of the time. Yet, last winter we had 3 times when that wood just did not give a very good fire at all. The weather conditions were all right, the chimney was clean, there was nothing else in the house to cause bad draft (like dryer running or exhaust fans), but we struggled just a bit with the fires. To counter this, I simply put some soft maple in with the ash and the fires took right off.

My point is that no matter what wood you burn, there can be a big difference from one time to the next and certainly from one stove to another. You certainly will do yourself a big favor if you get your wood supply at least 2-3 years ahead though as you will have fewer problems.

All in all, I can not say exactly what the problem is and that is why I just gave you some examples which I hope will probe your brain into maybe coming up with the right answer. Good luck.

 

[raybonz]

" What causes this shrinkage? For sure, you know the answer to that one."

Cold water will cause that!

:lol:

Ray

 

[Backwoods Savage]

Ray, I might have expected that one. :lol:

 

[skinanbones]

As for why it's smokes only on weekdays it could be that even thought you maybe leaving enought time to get the stove started, your rushing yourself and not being paitent enough with the stove. Where as on the weekend when you don't have to be somewhere your taking the time to babysit the stove and getting a favourable result everytime.

 

[pen]

What if the other stove is shut down? Does this only happen when they are both running at the same time? Are the competing for air? What if you crack a window when you are having the problem? If things improve then you may need to consider an outside air kit (oak).

Obviously the stove doesn't give a hoop-de-do about what day of the week it is. There is another variable coming into play that you are missing.

pen

 

[BrotherBart]

Turn the wood around to N/S in the Magnolia and let that sucker do what it is made to do. I am auditing the class. No grade on the paper needed. If you are going to try to burn in the Mag E/W, go see Vanessa for lessons.

http://woodheat.org/wood-heat-videos.html

Last video on the page. Efficient Wood Stove Operation

 

[begreen]

In a single story home I'm guessing draft is the issue. Not sure why without the stack specifics. The insert is going to vent straight up. The Maggy may just need more air or perhaps its connector has a couple 90's in it? A 10º temp differential isn't helping. Is the house really 55F?

 

[BrotherBart]

Look at this statement BG. "The WOOD STOVE is deep. The fire can be far back and the door is small. This has a constant smoking problem. You can’t open the door more than a few inches. Hard to start. Air wash does nothing to keep window clean."

Just burning E/W in the back half of a deep firebox just ain't gonna happen right. Gotta have a good fire up front to even char the stuff in the back. And even then the tight packed stuff in the back will burn like crap. Just too far for the primary air to travel and too much wood in the way.

 

[henkmeuzelaar]

What's possibly different on weekends that could influence the combustion process?
Here goes:

(1) you habitually clean the ash drawers out on Saturday morning
(2) you select some nicer looking splits because you want to show off to visitors
(3) an old fogey-stogey friend or family member comes over so you crack the windows
(4) a bunch of teenagers comes over and keep running the clothesdryer agauin and again
(5) the toilets and bathrooms are being used more, and thus the fans
(6) the whole house fan is programmed differently for Saturdays and Sundays to help make the house smell good
(7) the door between the house and the garage is being opened less (or more)
(8) people watch more TV and/or operate more lights (amounting to many kilowatt hours difference in heat being generated)
(9) 10 more people stay in the house, at about 100 W body heat each, they produce 24 kWh per day
(10)

sorry, soup's on and I have to leave for awhile.

Henk

 

[cottonwoodsteve]

Ok , now for my results.
These are facts that some people will have a hard time accepting.
Some answers were in the local area. But everybody is dancing around the sacred cows. Some didn’t even read and understand the conditions.
Still air and Ecco or Presto logs eliminates wood and wind problems.
No wind so no effect on chimneys, which are both on the same side. Straight chimneys, no bends, both inside.
Stacking wood East / West, North / South, Top / Down, Bottom / Up, or Missionary Position does not change the main problems.

Measured outlet of Magnolia. Not just what you see but measure the whole path. It looks like it has two 2 x 8 inch slots but there is a lip above this that limits it to two 1 x 8 inch slots.
Due to boundary layers, surface friction and a lot of other heavy physics, a narrow slot will flow less than a square opening of the same dimension. So let’s say this really only has about 12 square inch of equivalent flow.

A 6 inch round chimney or stove pipe has a 28 square inch flow area.

The Osburn has a nice lead in starting at about 3.5 inches then a few inches up narrows down to 1 5/8 inch wide and 18 inches long. Since it is longer, has a wider slot and has no center divide it flows much more per square inch than the Magnolia. Roughly it flows with the equivalent area of 26 square inches.
Total flow capabilities;
6 inch Pipe = 28 square inches
Osburn = 26 square inches with good lead in to smallest part.
Magnolia = 12 square inches. Not much lead in to the smallest part.

Magnolia people recommend removing one rear baffle brick to solve smoking problems. Translation = We made the outlet around the baffle too small and it smokes.
But wait there is more! The device with the smallest outlet has a bigger firebox.
Basically you are trying to start a stove with the damper more than halfway closed. 26 inches restricted to 12 inches. When it is going, a stove can have the damper closed half way, but not at low or starting.
The Osburn starts with the damper open. 28 inches only restricted to 26 inches. Not 12 inches. So it starts much easier.
Opening a window open helps a little but doesn’t really solve the problem. As we know from older stoves you can’t start them with the damper more than halfway closed no mater what the other conditions are.
As for the week day problem. PyMS was the closest.
The stove has a very restricted outlet. It doesn’t need much to really cause problems.
On some weekdays laundry was started after work. Then do things around the house. Later start dinner. House tight and to fairly recent Code. Kitchen and laundry room to Code.
When dinner is started ; The kitchen cooking stove hood blower ON, , now dark, so laundry room light, with included blower, is ON, Laundry now out of Washer and into Dryer, now Dryer blower is ON.
Cracking the window open doesn’t help. With 3 blowers going you need to Open the window! Why not the insert having problems?
With much bigger outlet smoke easily pours up into the pipe. Since it flows much better, a tight house or one exhaust blower doesn’t have an effect like it does on the Magnolia. Three blowers will affect it but we don’t have 3 exhaust blowers running when the insert has a fire. The insert doesn’t put out as much heat ( more heresy ) so we only use it in more relaxed times sitting in the living room on weekends. We don’t do laundry on weekends. The smoker stove is used on weekdays when we have a definite pattern and want a lot of heat now.
The problem that upsets me is the hostility and insulting tone of some of the “Help†in some of these forums.
If you have a problem it is implied you are too dumb to light a match and you obviously store your firewood in the swimming pool.
It is absolute heresy to imply that there could be something wrong with an EPA stove design. Well let me tell you folks. Under the same ideal conditions a device with a 26 square inch outlet will perform greatly different than a device with a 12 square inch outlet. People criticize by implying “I have the same stove and it works fine for me so therefore you must be stupid.†Well your stove with a two story chimney and laundry area in garage will act greatly different than my stove with a one story chimney and laundry area in house. Your stove with a large outlet will act greatly different than mine with an outlet less than half of yours.
They only have to work at the data taking points.
EPA stoves are not tested for ease of operation.
EPA stoves are not tested for operation during cooking or laundry.
EPA stoves are not tested for one story, two story and 3 story including basement.
EPA stoves are tested in large factory buildings. Not homes.
They are not tested in tight new homes and old drafty homes. At least in my installation manuals, I saw no reference to different install and operating instructions depending on your home conditions.
Let’s all admit EPA stoves are not all the same. And absolute heresy…. there may be some bad designs! Let’s admit what works in your house may not work in my house, even if you came over with your wood and expert firebuilding skills.
Let’s solve problem problems and not imply people are stupid.
Uh-oh, I got to go. I see some people in the village square piling kindling around a stake with my name on it.

 

[BrotherBart]

Yawn.

 

[begreen]

If you think that there is cheerleading for all EPA designs you haven't followed the downdraft threads. So the Magnolia needs a stronger draft. Good info for others. Generalizing this experience and applying it to all EPA stoves is bunk. The premise that older stoves worked just great in all conditions with all flues is also bunk. Ain't so.

 

[cottonwoodsteve]

I did not “Generalize†anything. I gave very exact conditions with exact devices.
I did not apply it to all EPA stoves. I very clearly said “some†EPA stoves may have design problems. I did not say “all†EPA stoves have design problems.
I very clearly stated some stoves may work very well in some settings.

 

[SKIN052]

Forums are great sources of information, this one being the best I have ever been on. Despite that, you still have to take the advice with a grain of salt and apply it to your issue. It can be hard to get all your points across on a forum so typically the first advice provided is to double check the basics, Draft, wood, chimney, type of stove, floor plan, etc. Once the experts here have a good understanding of what your set up is like then it makes it easier to pinpoint the issue.

If you need instant answers, call in a local stove expert, don't go to the internet. The internet is full of great info and not so great info, it is up to you to decipher what is what.

 

[pen]

I don't know what there is to admit here. Most all provided general suggestions to help with the problem because even the priciest of epa stoves on the market aren't perfect in every circumstance.

As far as people reading your post try using spacing between thoughts (paragraphs) and your posts would be much easier to get through.

pen

 

[djblech]

Almost all stove issues boil down to fuel or air. When a ? is asked here answers start from the simple and go to the complex. Without seeing your situation first hand it is hard to diagnose so suggestions are made. My Dad had a fireplace that would backdraft if the stove vent in the kitchen was turned on filling the house with smoke. I wouldn't have thought of that first because it was not a common problem. You won't find a better bunch of people than are here on Hearth. If you had been more patient someone would have suggested a OAK(outside air kit) which would solve your negative pressure (Air) problems.
Doug

 

[begreen]

I did not “Generalize†anything. I gave very exact conditions with exact devices.
I did not apply it to all EPA stoves. I very clearly said “some†EPA stoves may have design problems. I did not say “all†EPA stoves have design problems.
I very clearly stated some stoves may work very well in some settings.

Still waiting for a complete flue description on the Magnolia, did we miss that? Twice asked for. While you may have a complete picture of this installation, no one else does. And there are no resident psychics here that I know of.

EPA stoves are not tested for ease of operation.
EPA stoves are not tested for operation during cooking or laundry.
EPA stoves are not tested for one story, two story and 3 story including basement.
EPA stoves are tested in large factory buildings. Not homes.

This is a big generalization - I know PE stoves are tested under a variety of conditions (at least they said they were). I have an email into Woodstock to find out how they test their stoves. From what I can see it's in a small factory building. But I wonder if they also test in their homes? I know I would. And yes stoves are tested under different drafting conditions and ambient temps. Can they cover all conditions? No. Should they? No. Many times this is not a case of stove design at all. Instead it's a case of flue design. Many manuals are pretty helpful pointing out ideal size ranges and caveats for things like additional elbows or altitude effects. Some aren't. But that is just weak documentation and again, not necessarily stove design.

Let’s all admit EPA stoves are not all the same. And absolute heresy…. there may be some bad designs! Let’s admit what works in your house may not work in my house, even if you came over with your wood and expert firebuilding skills.
Let’s solve problem problems and not imply people are stupid.

That troublesome designs are out there has been admitted, talked about a length depending on the stove and the problem, many times over. Take some time to go back over the tens of thousands of posts here. As far as rude treatment, that is pretty uncommon here. In the thousands of posts we see here annually I would say that most people are treated equally and with respect. There always will be some folks with an attitude or having a bad day, but that can happen in a stove shop just as easily as on the internet.

 

[cottonwoodsteve]

Been busy didn't have time to do reply. I added smarter electronic control to my old relay logic heat pump. This extracts out about 2 to 5 % more heat. Works great. A heat pump from 1980 now acts like a 1990 model. This took a lot of schematic reading and operation understanding before I tackled the mod.

Back to wood;
Pix included. It is a 6 inch pipe all the way to nice clean screened cap at about 13 feet.
Pipe through ceiling and to top of cap is 6 inch in a 8 inch multi-wall pipe even above the roof.
It does not expand to 8 inches like the ceiling trim piece leads you to believe.
If I check the pipe, I have had it apart 3 times, it has a very strong draft with no stove connected. The light soot gets sucked up just with a breeze or temp differential. I have also made sure there is no soot piled up on the stove baffle blocking the outlet pipe. And as the factory says, I tried removing one baffle brick. It really helps the draft but you can see your flames and heat taking the quick way out. So I didn't leave it that way.

Normally I burn oak with some pine and eucalyptus. But you can see my test wood bricks in front.

I did have one of those fan boxes that go in the middle of the pipe. If you have a drafting problem definitely not a good idea.
Also the cross air tubes quickly condense out and insulate themselves with fluffy deposits, so you don't get much heat out anyway.

Didn't like the Osburn cover trim, too massive, especially above the insert. So I make my own using some of the old fireplace screen holder. There is a sound baffle in front of the air intake to cut down on the incessant blower whine. Osburn has a recessed side handle and some side exit vents so you have to angle in the trim near the insert to agree with these.

 

[begreen]

Nice going on the heat pump. Every little bit helps. Thanks for the input, we have very little info on the Magnolia being it's a newer stove. This will help others. As a test, I would take a 3 ft piece of pipe and add it to the 13' flue. It can be cheap galvanized vent pipe, this is just a test. It could be that it needs stronger draft to pull air through the secondaries it need strong draft. This test would help determine it. Or like you say, it just could be a crappy design.

The Osburn glass looks pretty soiled, as if the stove is not being run hot enough. Have you tried running the stove much hotter? Is there a blower on the stove? I would expect it to look more like this:
https://www.hearth.com/econtent/index.php/forums/viewthread/32665/

 

[cottonwoodsteve]

The pipe is on the low side of the roof so adding another piece will make me uncomfortable without guy wires. I don't know if it would be required but I don't want to stress the roof pass through in a high wind.

I am not into perfect cleaning. But I have noticed I can burn off a light coating but it goes right back on as the fire dies down.
The air wash does absolutely nothing.
It has the standard blower on the back.

Another experiment I did;
With a center punch I have dimpled a pice of metal with a curve top. I put this in the lower door gasket area. It makes a very slight gap, less than 1/16.
It kepted the bottom 2 1/2 inch of the glass clean through a few burns. But not worth leaving in.

I notice no effect with the built in air wash. The air goes down and away from the window. It has no way to make a sharp bend to go around the 1/4 inch metal, past the gasket area and out to the window and then make another sharp bend to go down the window. It just doesn't work.
Air wash on Osburn works great even on a much bigger glass area.

The air coming out of the Osburn is relatively low flow but hot, so it goes straight to the ceiling. Just out of the picture is a small desktop fan that clamps onto the stones. This greatly helps in blowing the exit air sideways and mixing it with the room air. This makes the room warmer at the people level.

 

[SKIN052]

Where does the secondary air get pulled into your stove? On the Summit it is at the back of the stove and you can clearly see the channel leading into the Baffle. Any chance that the secondary air intake is clogged somehow? Packing material?

 

[madison]

Two questions, in the picture of the wood stove, it appears as the pipe transitions from 6" to 8" at the ceiling. Is this observation correct? If yes, the draft will be reduced because of the larger diameter pipe.

Is the insert a masonry chimney?
/////////////////////////
It appears that the manual for the Magnolia 2015 calls for a minimum of 12 feet of 6". If the chimney is short and 8", as begreen suggested, experiment with a taller stack.

One other thought, could you describe the geography of the location of the home, ie northern California valley surrounded by 200 ft redwoods. We had a very tall exterior masonry chimney on the north side of a totally shaded home, and that chimney rarely drafted very well, and would have back drafts and stinky rooms in the summer.