Lopi Leyden problem/help? please?

[jasonb]

Thanks to everyone here first of all for everything I've learned in the past 10 months reading this site.

I bought a leyden last spring. Couldn't get the secondary lit... pipe temps very low. Attributed it to poor draft and sleeved my chimney with a liner. In all it's a 1' rise, about 3' sideways at a slight angle to the chimney, then about 21' up and out.

I think initially i was burning the stove too hot to get the secondary going. i'd get it up to about 650 before engaging the secondary. When i did engage the secondary i'd leave it on half engaged to let the back warm up, which i'd wait until the back shroud was 600+ before closed the bypass completely. Been doing this since november and was getting frustrated because i'd burn up a bunch of my wood before getting the secondary going, and once it was going the stove was too hot and burned the wood too fast. Sometimes the secondary wouldn't light the first time, and i'd have to start the process over wasting even more wood.

Anyways, a few days ago i realized i needed to forget what i thought i knew about the stove and start over. I moved my flue thermo from after the bend (i had read 3' up the pipe on here) to 6-8" over the stove on the initial vertical pipe. This seemed to give me much more accurate and responsive readings. I also started to engage the secondary sooner, and like magic it would work. I never remembered it being that easy... its not like i didn't try that in the first place when i had no luck really...

So FF to today and despite getting the secondary going nice and early with proper box temps recently, the stove still slowly and steadily warms up to the same 700 degrees in from of the pipe and the shroud on the back over the secondary heats to 800+. Right now the R side is at 830 and the L side is at 730. The stove temp pretty much maxes out at 700 and it stays there until the secondary kicks out. Pipe goes up to around 500 and stays there.

Once the stove maxes out it will start to flame a little in the fire box. Like ghost flames but they're steady.

I was thinking maybe air leak and started checking out the door/lid/ashpan seals and they all seem ok? I did the dollar bill test and it seems fine.... I've only been using the stove for a few months so i guess i'd be surprised if a seal was bad anyways... Maybe i need to adjust the door tight? It seems pretty tight as is though.

Does anyone have any ideas for me? Thank you very much in advance.

 

[branchburner]

The stove temp pretty much maxes out at 700 and it stays there until the secondary kicks out. Pipe goes up to around 500 and stays there.


I was thinking maybe air leak.

Welcome to the forums!

My stove has a similar design, and they DO like to burn hot. You may not have an air leak other than the non-adjustable secondary air inlets, which can pull in a bit too much and burn even hotter with a strong draft in some instances (maybe drafting harder with cold weather?). Some people have had borderline overfire problems with the Leyden, the Oakwood, and certain VC stoves with similar design.

The bypass on my stove is the damper, either fully open or fully closed to engage the secondary, with no ability to adjust in between. I thought yours was the same, but no?

You didn't mention anything about your primary air setting. I adjust that at different stages of the burn, before and after I shut the bypass. What is your procedure with primary air?

Assuming you have no leaks and just a setup that burns hot, even with no primary air, here are two ideas. The first is very easy, and has made a huge difference for me, since my stove sits halfway in a fireplace and has no blower: I have a small fan on one side of the stove, placed on the floor a few inches out in front, that blows cool floor air toward the back of the stove when it is really hot. This both cools the stove a bit by transferring heat away from it, but also aids the convection loop that pushes the warm air out from behind the stove and into the living space. Do you have a blower? If not, try this for sure.

The second idea, which I may do but haven't yet, is to install a pipe damper to help slow the draft when the stove seems excessively hot. (A variation on this is to alter the secondary air inlets by partially blocking them with foil, which I've done, or add a mechanism to make their inflow adjustable, which I also have intended to do. Even minor stove modifications are ill-advised, however, to the extent that they void any warranty. And BTW, if you ever make a warranty claim, the hottest your stove ever got was 799F, and NOT 800+!)

And finally, what sort of burn times are you getting with a fully loaded stove? A short burn usually means too much air.

 

[jasonb]

Welcome to the forums!

My stove has a similar design, and they DO like to burn hot. You may not have an air leak other than the non-adjustable secondary air inlets, which can pull in a bit too much and burn even hotter with a strong draft in some instances (maybe drafting harder with cold weather? I thought about that too. certainly could be..). Some people have had borderline overfire problems with the Leyden, the Oakwood, and certain VC stoves with similar design.

The bypass on my stove is the damper, either fully open or fully closed to engage the secondary, with no ability to adjust in between. I thought yours was the same, but no? Its a handle that I've learned fully closes the bypass in 6 clicks... So i turn it 3 clicks. I saw someone on youtube doing this with the same stove is where i picked up the habit...

You didn't mention anything about your primary air setting. I adjust that at different stages of the burn, before and after I shut the bypass. What is your procedure with primary air? I leave it fully open. After i close the bypass i wait about 5 minutes then close the air halfway... about 5 minutes later i either go to all the way closed or at that point leave it open a slight bit for a few more minutes.

Assuming you have no leaks and just a setup that burns hot, even with no primary air, here are two ideas. The first is very easy, and has made a huge difference for me, since my stove sits halfway in a fireplace and has no blower: I have a small fan on one side of the stove, placed on the floor a few inches out in front, that blows cool floor air toward the back of the stove when it is really hot. This both cools the stove a bit by transferring heat away from it, but also aids the convection loop that pushes the warm air out from behind the stove and into the living space. Do you have a blower? If not, try this for sure. No blower. Last night i actually put a small fan under the stove near the back to try to circulate air between the back of the stove and the shroud. I couldn't tell the difference between the air moving out the top of the stove so i removed it.

The second idea, which I may do but haven't yet, is to install a pipe damper to help slow the draft when the stove seems excessively hot. (A variation on this is to alter the secondary air inlets by partially blocking them with foil, which I've done, or add a mechanism to make their inflow adjustable, which I also have intended to do. Even minor stove modifications are ill-advised, however, to the extent that they void any warranty. Thats interesting... Tin foil.... I didn't think of that. I started out with a lack of draft so i'm hesitant to think i have too much draft... perhaps i do because of the extra cold weather now.... My flue pipe doesnt really get all that hot more than a few feet from the stove. Is the air intake the circular hole in the back bottom of the stove, do you know? And BTW, if you ever make a warranty claim, the hottest your stove ever got was 799F, and NOT 800+!) Yea i considered that. The manual says to take stove temps on the top right in front of the flue, above the top lid. So i sort of assumed that higher temps where the secondary is is expected? Maybe not though.... I don't think at that spot I've gotten over 800... I know i also read temps 800+ void the warranty. So i do appreciate the suggestion.

And finally, what sort of burn times are you getting with a fully loaded stove? A short burn usually means too much air.

Right now i'm at about 5 hours. Stove top/secondary top both down to about 500. Box is maybe 1/3 filled now... I'm not sure what condition the logs are in now... could be half charcoal for all i know... My logs don't fill the box completely lengthwise and leave maybe 4-5 inches space between both sides combined.

Last night i left the stove burning for 6 hours. before reloading. When i reloaded it had a couple charcoled logs that easily broke into pieces, and left me with a very hot, deep coal bed about 4" deep.

I'm never sure what people consider a cycle. Until the stove is cold? When all the wood is gone and only coals?

^REsponses in quote in bold

Thank you very much for taking the time to write such a detailed and thorough response. I really appreciate it!

 

[branchburner]

My pleasure... sounds like you are getting a decent burn that's throwing good heat, and I wouldn't worry too much about 700-800+ temps on the afterburner... my stove also gets hotter back there than on the top, where it cruises at 500+. Lately I've been well below my highest temps on the AB, but I attribute that perhaps to differences in wood,,, size, type, and moisture level seems to give lots of variation in temps.

I do my air adjustment in a similar manner, and get a similar burn time... I think maybe the Leyden just tends to run a bit hotter. I doubt you have a leak, as others have run even hotter apparently without one. You were likely correct about the original reason for poor draft being no liner -- your AB wouldn't be cranking so well now without good draft, as that seems crucial to it kicking in and not stalling. I'd try the fan again, but about a foot out and to the side, angled to blow behind and bring cooler air to the general area where the AB is throwing its heat.

Happy heating!

 

[lumbering on]

My lid was cast with a slight warp, and leaked air.
Another user on this site also had a warped lid, ordered a new lid, and it was also warped.
Also, check the gasket on the bypass damper. I overlooked it at first.