Lopi Leyden advice

[bholler]

I believe that the Isle Royale is a burn tube design. If so, it's the only one I know of.

What do you mean the only one there are more tube stoves out there than cat stoves and way more than down drafts. I believe all quads are tube stoves and most lopis are.

Who makes a hybrid-cat w/ burn tubes that features a full view of the secondary combustion?

I know regencies hybrids do the cat is obscured by a flame impingement shield but you can still see the glow. I know they are others but that is the only one I know of off hand.

I like being able to view the fire, and think of it as being a fairly recent technological advance in wood stoves. No wood stove used to offer that feature; now most of them do. It's a great upgrade in aesthetics as well as giving us more knowledge about the burn.

Not really there have been stoves with windows for a long time. But only in the past 20-25 years are there ones that the glass stays clean enough to really see the fire through regularly.

 

[webby3650]

Thank you, branchburner. Yes, I was referring to the ratcheting modification that Lopi provided as an improvement to the bypass lever operation. A simple latch would have been easier to design. Looking at the kit, my assumption was that this was a factory modification to allow the degree of bypass to be adjusted by the user - since doing so was clearly necessary in order to get the stove to run correctly. I set mine to allow for for six different bypass positions including full open or fully shut.
I'm sure I'm not the only person who found that reliable burning required the bypass to be only partly closed. As a bonus, we can sometimes get a secondary burn going right at the top of the firebox. Unusual & beautiful bright whispy dancing flames. It would appear that a reliable secondary burn on this stove requires being able to visually see the secondary flames. Is that true of all stoves? I suspect it is... BTW, I usually run mine at about 60% closed. That is a position that works well for my stove and I have marked the ratcheting bypass lever so that it is repeatable.

No, the original owner's manual does not mention running with the bypass lever partly engaged. But keep in mind that manual was written before the company made the modification to the lever that allows for positive locking at partial engagement.

Frankly I didn't find the owner's manuals to be correct as to the stove operation. That didn't surprise me, and that was good since this one has a number of questionable passages. On page 21 regarding bypass lever operation, the bypass lever is described as being "pulled out or pushed in". That's clearly incorrect. The bypass lever is rotated; not pushed at all. It is the air intake that works by being pulled out or pushed in.
On the next page of the manual it recommends that after starting the stove it be run with the bypass wide open and the air flow at maximum for up to 45 minutes in order to get the stove up to heat before engaging the bypass.....
Still learning,
rScotty

This bypass ratchet revision was not intended to allow the bypass to have multiple range settings. It's either open or closed. The rachet was just a simple way to prevent the bypass from falling open during operation.

Don't you ever hear a low rumble coming from the back of the stove? I sure did. That's the secondary combustion taking place in the combustion chamber, like the stove was designed to do. With the bypass 40% open you are losing most of your efficiency. Not good

 

[rScotty]

This bypass ratchet revision was not intended to allow the bypass to have multiple range settings. It's either open or closed. The rachet was just a simple way to prevent the bypass from falling open during operation.

Don't you ever hear a low rumble coming from the back of the stove? I sure did. That's the secondary combustion taking place in the combustion chamber, like the stove was designed to do. With the bypass 40% open you are losing most of your efficiency. Not good

I repectfully disagree. It would have been much easier to make a positive one-position latch. The only reason to imake it more complex would be to allow for adjusting the percentage of gases being bypassed. the new fractional bypass attachement is entirely too nice not to have been intentional.

Suppose I describe the way this stove works and see if it sounds familiar? Say the stove has started up and been burning nicely for an hour. The pipe is hot too. The air intake control which started out wide open is now back to being almost entirely closed to prevent too much of a primary combustion fire. There is already a reasonable bed of coals forming on the ashes. The stove itself is at a reasonable temperature....pretty darn hot in fact.
Now at this point if the bypass is engaged 100% and the air opened a little more....to less than a third of the way open, the thing that will probably happen is that the fire will gradually just go out. But every once in a while if I open the air intake just a hair farther than a third of the way open I will begin to hear the growling that you are talking about and the stove will rapidly begin to get very hot. I was a welder and machinist for 30 years. I understand hot metal. I simply will not run any stove in that manner. Especially a cast one. After ten years with this stove I know it's tricks. And it's main trick is how much it is incredibly sensitive to the position of the air control and the draft/bypass lever.

I believe that with the help of this forum I have finally figured this stove out. I think that the best way to run the Lopi Leyden is more like old style wood stoves were run before secondary and/or catalytic combustion were every invented by the stove industry. In those days the whole firebox of a woodstove was designed to do what is now called "primary combustion". The rate of primary combustion is adjusted by paying close attention to the air intake position, and - at least in the case of the Lopi Leyden - the bypass is used in partial engagement where it functions more as a flue damper to assist in controlling the rate of primary combustion. I also believe that run that way the Leyden is a reasonable and safe if rather old fashioned wood stove. However, unning the Leyden in secondary combustion mode is to be avoided. It doesn't run dependably in secondary combustion mode.
rScotty

 

[branchburner]

I repectfully disagree. It would have been much easier to make a positive one-position latch. The only reason to imake it more complex would be to allow for adjusting the percentage of gases being bypassed.

Say the stove has started up and been burning nicely for an hour. The pipe is hot too. The air intake control which started out wide open is now back to being almost entirely closed to prevent too much of a primary combustion fire.

The rate of primary combustion is adjusted by paying close attention to the air intake position, and - at least in the case of the Lopi Leyden - the bypass is used in partial engagement where it functions more as a flue damper to assist in controlling the rate of primary combustion.

So what you are describing is at odds the opinion of webby3650, but what he and I were speaking of is the use of the bypass during SECONDARY combustion... for that to work, he is correct, it must be closed 100%. But I do agree with you, for PRIMARY combustion a partially closed bypass makes perfect sense.

What I discovered with my Oakwood was that in trying to establish a deep coal bed after a cold start, a fully open bypass (my only option) would allow the flue (and sometimes even the stove top) to reach very high temps. In that long warm-up period before I could close the bypass to get secondaries, even with my air intake shut way back I was losing tremendous amounts of heat up a very hot flue.

So you are right - the bypass used in partial engagement functions as a flue damper to assist in controlling the rate of primary combustion. And with my stove, not having that option, I considered putting in a pipe damper for that very reason. Even when you shut your primary air intake, you still get a flood of uncontrolled air coming in through the hidden secondary air intakes. In tall chimney setups or conditions of high draft, this initial burn phase means a hot pipe and wasted fuel.

(This is why I consider the downdraft technology to be among the least efficient designs if you are going to run multiple smaller, shorter fires in the fall and spring.)

 

[branchburner]

I also believe that run that way the Leyden is a reasonable and safe if rather old fashioned wood stove. However, running the Leyden in secondary combustion mode is to be avoided. It doesn't run dependably in secondary combustion mode.

Well, yes, but here you are just admitting that this stove has fatally flawed design. Even if you can run it fairly efficiently with good control... and I believe you probably CAN get some good secondary combustion within the main firebox, at times... what's the point of a modern EPA stove with secondary burn technology if you can't ever use that technology?

 

[branchburner]

I believe that the Isle Royale is a burn tube design. If so, it's the only one I know of. Who makes a hybrid-cat w/ burn tubes that features a full view of the secondary combustion?

The Isle is one of the only TOP-loading ones, and so far as I know it has been discontinued.

One hybrid-cat w/ burn tubes that features a full view of the non-cat secondary combustion -- a really GREAT light show at times -- is the stove I just bought, the Woodstock Ideal Steel (larger version of the Absolute that I beta-tested). Making me look forward to winter!

 

[webby3650]

I repectfully disagree. It would have been much easier to make a positive one-position latch. The only reason to imake it more complex would be to allow for adjusting the percentage of gases being bypassed. the new fractional bypass attachement is entirely too nice not to have been intentional.

Suppose I describe the way this stove works and see if it sounds familiar? Say the stove has started up and been burning nicely for an hour. The pipe is hot too. The air intake control which started out wide open is now back to being almost entirely closed to prevent too much of a primary combustion fire. There is already a reasonable bed of coals forming on the ashes. The stove itself is at a reasonable temperature....pretty darn hot in fact.
Now at this point if the bypass is engaged 100% and the air opened a little more....to less than a third of the way open, the thing that will probably happen is that the fire will gradually just go out. But every once in a while if I open the air intake just a hair farther than a third of the way open I will begin to hear the growling that you are talking about and the stove will rapidly begin to get very hot. I was a welder and machinist for 30 years. I understand hot metal. I simply will not run any stove in that manner. Especially a cast one. After ten years with this stove I know it's tricks. And it's main trick is how much it is incredibly sensitive to the position of the air control and the draft/bypass lever.

I believe that with the help of this forum I have finally figured this stove out. I think that the best way to run the Lopi Leyden is more like old style wood stoves were run before secondary and/or catalytic combustion were every invented by the stove industry. In those days the whole firebox of a woodstove was designed to do what is now called "primary combustion". The rate of primary combustion is adjusted by paying close attention to the air intake position, and - at least in the case of the Lopi Leyden - the bypass is used in partial engagement where it functions more as a flue damper to assist in controlling the rate of primary combustion. I also believe that run that way the Leyden is a reasonable and safe if rather old fashioned wood stove. However, unning the Leyden in secondary combustion mode is to be avoided. It doesn't run dependably in secondary combustion mode.
rScotty

I don't need you to describe how the stove works. I've owned them and work on them all the time. I've been as deep into a Leyden as you can get..
Leaving the bypass partially open was never the intention, not ever. I'm glad you found a way to make a flawed design work your particular setup.

 

[rScotty]

Well, yes, but here you are just admitting that this stove has fatally flawed design. Even if you can run it fairly efficiently with good control... and I believe you probably CAN get some good secondary combustion within the main firebox, at times... what's the point of a modern EPA stove with secondary burn technology if you can't ever use that technology?

This is amazing, BranchBurner....now that we are all using the same terms, we find that you and I and Webby and several others are basically all in pretty close agreement! I now can see why the intention of a secondary bypass is for it to be closed 100% - what confused me is that the Lopi Leyden just doesn't work well that way. Using this forum's search function, I found that previous posters also mentioned their Leyden's bypass mechanism. I'd like to think that someone at the factory realized that their stove design was indeed fatally flawed at 100% bypass, so this wise factory guy went ahead and designed a ratcheting bypass that allowed Leyden owners to safely do exactly what they were all doing anyway - which was running them at partial bypass.

Branchwood, your experience with your Oakwood sure sounds remarkably similar to mine with the Lopi Leyden. I think the stoves are similar - perhaps even from the same designer/manufacturer.

Living with this stove for 10 years now, I am confident that with partial engagement the bypass makes a good damper for primary burning for occassional use. Just as you say. And yes, with careful adjustment and frequent tending I can even get some secondary burn within the primary chamber itself. I now feel more comfortable that the Leyden can be used within limits while I look for a our next stove, which will be a model designed to take advantage of the newer technology and built to the highest standards. That's always been the goal. Compared to what they do for us, wood stoves just aren't expensive enough to make price the most important factor.

I came to this forum hoping to learn more about stove technology because it is time to buy a better stove. And while doing that, I also needed to get a better understanding of the problems with the Leyden. What I found is that my problems with the Lopi Leyden aren't unique. But I've also come to understand that now that I in educated in how it works I can live with the shortcomings while looking for another stove. - I also believe that manufacturers can't advance technology without making mistakes along the way. I'm only irked when they use that process without admitting to the mistakes as well as the successes.

Nope, I don't yet know all the features that I want in the next stove, but one thing is for sure....I won't again buy a stove that has combustion taking place some place inside the stove where I can't see it unless it is of bulletproof double-box construction or I have real control over it - maybe both. No more hidden gimmicks. That eliminates the current group of downdraft rear secondary burn types, but there are other technologies.

BranchBurner, your new Woodstock hybrid catalytic with burn tubes sounds like it solves many problems for your application. I'm intrigued; and wonder if it allows you to watch and fine tune the combustion in the cat chamber? Their Absolute model is sized about right for our site.
I'm learning from my mistakes and need to know only a little more before deciding.
Enjoy and thank you guys,
rScotty

 

[branchburner]

I'd like to think that someone at the factory realized that their stove design was indeed fatally flawed at 100% bypass, so this wise factory guy went ahead and designed a ratcheting bypass that allowed Leyden owners to safely do exactly what they were all doing anyway - which was running them at partial bypass....

Well, webby may very well be right that it was never really the intention, but just happens to work in primary-burn mode. You'd have to find someone at the company to confirm, but I doubt many people were ever trying to run at partial bypass. Maybe some had a pipe damper, which would slow the fire in both primary AND secondary mode, as needed.

The stove is not 100% flawed, as it can work with very dry wood and draft that is sufficent but not OVER-sufficient. But after a few years, it is not unusual for the combustion package in some of these models to degrade or get clogged with ash so that it works less well, or not at all. It is best not to remove it to clean, but after a point there are some situations where it really must be removed and potentially replaced, as external vacuuming is no longer sufficient.

I wonder also... how seasoned is your wood? I find with the Oakwood that many species need a full two years cut/split/stacked to get the afterburner to fire off reliably. It also takes a huge learning curve of using the right size and configuration of wood (not covering the shoe brick) and fine-tuning the timing of bypass closure and air supply. Basically, a PITA!

So I agree....I won't again buy a stove among the current group of downdraft rear secondary burn types. The Woodstock hybrid cat with burn tubes won't allow you to watch the cat, but with practice and attention to the air control, I think you can fine tune the combustion in the cat chamber to some degree.

 

[begreen]

The problem with a fussy stove is that even if the setup works ok in average conditions, these conditions don't stay the same. Outdoor temps vary, in some places dramatically, changing draft; wood varies both in species and dryness; wind varies too.

 

[rScotty]

I wonder also... how seasoned is your wood? I find with the Oakwood that many species need a full two years cut/split/stacked to get the afterburner to fire off reliably. It also takes a huge learning curve of using the right size and configuration of wood (not covering the shoe brick) and fine-tuning the timing of bypass closure and air supply. Basically, a PITA!

Good question! Perhaps we should have started there. Although we live in a pine and fir forest and most people who live around here burn those woods I don't burn pine or fir. Too much resin in it for me no matter how long it is seasoned. Besides, those trees are my friends....

What I do is start my fire with aspen & oak scraps from a cabinet maker. After the fire starts, we burn oak blocks for the long burn and really nothing else unless I've got some seasoned fruit wood - but that's rare since there is a ready source of 4x6x9" oak heartwood blocks from a local mill. This is scrap to them, The blocks are the ends cut off when an oak billet is cut to length after seasoning and before being treated. The blocks are sold by the truckload. A great resource & inexpensive. The mill seasons the wood for years and then we season them for at least another year. So the wood is very consistent. Dry oak keeps just about forever.
rScotty

 

[bholler]

Although we live in a pine and fir forest and most people who live around here burn those woods I don't burn pine or fir. Too much resin in it for me no matter how long it is seasoned.

That is not true at all pine and fir are perfectly fine to burn if dry. It is much less dense so it has fewer btus than an equal volume of hardwood but there is nothing wrong with burning it.

This is scrap to them, The blocks are the ends cut off when an oak billet is cut to length after seasoning and before being treated.

But what moisture content do they dry to? And how do you stack those blocks? If they are stacked tight they have no airflow at all and will not season well at all. I am not saying this is what is causing problems down draft stoves are very fussy and hard to get working right. But you should really check the moisture content of the wood to be sure.

 

[webby3650]

This is amazing....now that I am using the proper terms, we find that you and I and webby and several others are basically all in pretty close agreement! I now can see why the intention of a secondary bypass is for it to be closed 100% - what confused me is that the Lopi Leyden just doesn't work well that way. I'd like to think that someone at the factory realized that their stove design was indeed fatally flawed at 100% bypass, so this wise factory guy went ahead and designed a ratcheting bypass that allowed Leyden owners to safely do exactly what they were all doing anyway - which was running them at partial bypass.

Branchwood, your experience with your Oakwood sure sounds remarkably similar to mine with the Leyden.

Living with this stove for 10 years now, I am confident that with partial engagement the bypass makes a good damper for primary burning for occassional use. Just as you say. And yes, with careful adjustment I can even get some secondary burn within the primary chamber itself. I now feel more comfortable that the Leyden can be used within limits while I look for another stove.

I came to this forum hoping to learn more about stove technology because it is time to buy a better stove. And while doing that, I also needed to get a better understanding of the problems with the Leyden. As for the Leyden, now that I understand it I can live with the shortcomings while looking for another stove. - I believe that manufacturers can't advance technology without making mistakes along the way. What irks me is when they don't admit they've made a mistake.

I don't yet know all the features that I want in the next stove, but one thing is for sure....I won't again buy a stove that has combustion taking place some place inside the stove where I can't see it unless it is bulletproof or I have real control over it - maybe both. No more hidden gimmicks. That eliminates the current group of downdraft rear secondary burn types, but there are other technologies.

Your new Woodstock hybrid cat with burn tubes sounds like it solves many problems. I'm intrigued, and wonder if it allows you to watch and fine tune the combustion in the cat chamber. Their Absolute size is indeed about right for our site.
I'm learning from ny mistakes and need to know more about it before deciding.
Enjoy and thank you guys,
rScotty

You wil never ever get anyone at Lopi to admit that any of their products were inferior. They will admit it though, after they've discontinued it and have a better design.. They are such an arrogant company! The factory rep would never admit any fault with the Leyden when I went toe to toe with him. He even said it was the same proven non-cat design that VC had been using for years...Then I bought the cape cod and it experienced all the failures that Lopi failed to acknowledge... Lopi won't get anymore of my money!

 

[rScotty]

That is not true at all pine and fir are perfectly fine to burn if dry. It is much less dense so it has fewer btus than an equal volume of hardwood but there is nothing wrong with burning it.

But what moisture content do they dry to? And how do you stack those blocks? If they are stacked tight they have no airflow at all and will not season well at all. I am not saying this is what is causing problems down draft stoves are very fussy and hard to get working right. But you should really check the moisture content of the wood to be sure.

On the pine and fir what I don't like isn't the lack of density as much as the resin and pitch. Seasoning doesn't change those tarry things. I've burned them in past years It became a matter of preference & how often I wanted to clean out my stovepipe. There's less cleaning with the oak. But I'd burn pine in a pinch if it was all we had. It's just that with all the oak blocks available burning pine isn't necessary.

As to moisture content of seasoned wood here, that depends on the RH of the air. It's dry out here in the high western mountains. Wood that is under cover and insulated from the ground will eventually get into equilibrium with the humidity of the air, which averages about a little less than 10% annually. Although it can average 11% in Nov, Dec, & Jan. I agree that the way wood is stacked and spaced makes a noticible difference in the short term. After a few years the RH of the air is what matters.
Folks here sort of take the dryness for granted.

But it would be fun to measure the moisture of the wood anyway. I may take your advice and get a moisture meter. Available online? Any favorites? Hmm....I wonder how best to get past the surface of the wood when measuring moisture content??..... After all, we want to measure interior seasoning rather than the surface; the surface mostly reflects the RH of the recent air. My guess is that it's common to drill a couple of holes and then put the probes in the holes. But how deep and how far apart should the probes go? Or am I missing something...What's the accepted method?
rScotty

 

[rScotty]

You wil never ever get anyone at Lopi to admit that any of their products were inferior. They will admit it though, after they've discontinued it and have a better design.. They are such an arrogant company! The factory rep would never admit any fault with the Leyden when I went toe to toe with him. He even said it was the same proven non-cat design that VC had been using for years...Then I bought the cape cod and it experienced all the failures that Lopi failed to acknowledge... Lopi won't get anymore of my money!

Webby, I sure do sympathize. After all Lopi got my money too!

As a young man I used to get all bent and ride around on my high horse believing that everyone should "man up" & accept responsibility for their mistakes. I still feel that way, but with age came the realization that just wasn't going to happen very often.

Now as an old, old man I've come to believe that since everyone makes mistakes and few admit to them, what matters more to me now is whether they learn from those mistakes. So I'll look at Lopi and see how they've done. But you can bet I'll be looking more deeply this time.
rScotty

 

[branchburner]

On the pine and fir what I don't like isn't the lack of density as much as the resin and pitch. Seasoning doesn't change those tarry things. I've burned them in past years It became a matter of preference & how often I wanted to clean out my stovepipe. There's less cleaning with the oak

What that likely means is that your oak was drier, because resin and pitch in dry softwoods should combust completely if the wood is fully seasoned. While it can make them a PITA to handle when green, resins are NOT a direct source of creosote accumulation in chimneys. Creosote is a result of incomplete combustion, regardless of wood species.

To the degree people find more creosote with softwoods that are fully dry, it is likely because their technique in burning (air supply, damper control, etc) is causing less complete combustion. Added to that, the lower density means a shorter and lower-BTU fire for a fully loaded stove, meaning more startups are required if using that wood. Since startup involve lots of smoke and no secondary combustion, the more of them you have the more creosote you are likely to get.

 

[bholler]

But it would be fun to measure the moisture of the wood anyway. I may take your advice and get a moisture meter. Available online? Any favorites? Hmm....I wonder how best to get past the surface of the wood when measuring moisture content??..... After all, we want to measure interior seasoning rather than the surface; the surface mostly reflects the RH of the recent air. My guess is that it's common to drill a couple of holes and then put the probes in the holes. But how deep and how far apart should the probes go? Or am I missing something...What's the accepted method?
rScotty

For firewood any cheap meter will be accurate enough you can get them for around $30 lots of places. As far as using it you split a piece and measure on the fresh split face in the middle.

 

[Woody Stover]

For firewood any cheap meter will be accurate enough you can get them for around $30 lots of places.

If you have a Harbor Freight there, I think they have one for about $15. Or you could... https://www.hearth.com/talk/threads/using-a-multimeter-to-measure-wood-moisture-level.40033/

 

[begreen]

What that likely means is that your oak was drier, because resin and pitch in dry softwoods should combust completely if the wood is fully seasoned. While it can make them a PITA to handle when green, resins are NOT a direct source of creosote accumulation in chimneys. Creosote is a result of incomplete combustion, regardless of wood species.

We burned fir exclusively last year. Just cleaned the chimney two days ago and got a total of about 5 ounces of soot and sote.

 

[rScotty]

For firewood any cheap meter will be accurate enough you can get them for around $30 lots of places. As far as using it you split a piece and measure on the fresh split face in the middle.

Simple and elegant. Makes sense. I like it.

 

[Woody Stover]

We burned fir exclusively last year.

Where did you get it, grabbing road kill? Oh, I mis-read...carry on.