Has the Green Mountain 60 been Updated?

[Simon Says]

Hi All:

I placed an order for a Green Mountain 60 recently. Delivery and install scheduled for early December. I thought I had done my research until I stumbled on this forum and the reported issues of back-puffing/smoking when the door is opened. I called the dealer to ask about the reports of smoking/back-puffing. I was told that Hearthstone came out with a recent update/change to the baffle that addressed the issue; that all their Green Mountain 60s in stock are less than a month old, and as such, they all include the change modification.

Can anyone opine on whether Hearthstone did modify the baffle recently to address the reported issue of smoking/back-puffing when the door is opened?

 

[tabner]

I don’t think we have that answer here, yet. Perhaps you will be the one to provide it 😊
I think the smoke is not so much of an issue if you have good draft. The stove’s manual seems to require a pretty high amount of draft. Can you describe your chimney/flue setup?

 

[Simon Says]

I don’t think we have that answer here, yet. Perhaps you will be the one to provide it 😊
I think the smoke is not so much of an issue if you have good draft. The stove’s manual seems to require a pretty high amount of draft. Can you describe your chimney/flue setup?

Stainless steel liner (7 inch) in chimney block chimney. I would estimate 24-30 feet of chimney above where the stove pipe will go in. Below that another 8-12 feet for a clean-out tee in the basement. I had the chimney cleaned and OKed for use. SS liner is in good condition I am told. I was not given any specs on draft from the chimney cleaner. The chimney is capped with a cap that is open on the side, but by visual inspection, I think I would like the cap to extend a little higher above the chimney; not sure if this will have a noticeable impact on draft. One good thing is it stays relatively windy in the winter months in our location, which I hope will work in our favor in terms of draft.

The chimney has not been in use for the entirety of the time we have owned the house. Though the house was clearly set up for wood stove use, at some point someone opted to remove the wood-stove.

I am somewhat puzzled by the reported issues with the Green Mountain 60. As to my untrained eye, the GM60 has the same specs as the Shelburne, it would appear the same build and design as well, except for the rear pipe option and ornate design of the Shelburne.

If the Sheldburne was a little smaller and simpler visually, I would have gone that route.

 

[tabner]

That’s a pretty tall chimney, should draft well. Make sure the 8 feet going down into the basement with the T is sealed well, you don’t want the bottom of the liner sucking cold air in from the basement, and detracting from your draft.
My GM60 is running right now. Works great. I took a video last night of the secondaries firing, every single hole on the secondary air ports was firing, pretty cool. I’ve also closed it down tight and had the glowing cats with no visible flames, like a true cat stove.
The only problem I have had with it is just smoke out the door on reloads - but some percentage of this issue (probably a large percentage) is me learning /experimenting when to do reloads. I need to get better at that.
This is why I’m curious about some baffle measurements when you get your stove. If it is a slightly smaller baffle for this reason, it might be something I wanna try.

 

[Simon Says]

That’s a pretty tall chimney, should draft well. Make sure the 8 feet going down into the basement with the T is sealed well, you don’t want the bottom of the liner sucking cold air in from the basement, and detracting from your draft.
My GM60 is running right now. Works great. I took a video last night of the secondaries firing, every single hole on the secondary air ports was firing, pretty cool. I’ve also closed it down tight and had the glowing cats with no visible flames, like a true cat stove.
The only problem I have had with it is just smoke out the door on reloads - but some percentage of this issue (probably a large percentage) is me learning /experimenting when to do reloads. I need to get better at that.
This is why I’m curious about some baffle measurements when you get your stove. If it is a slightly smaller baffle for this reason, it might be something I wanna try.

The bottom of the T is capped. There will be two 90 degree turns to the chimney, one into the wall, the other constituting the connection into the chimney.

Just curious, are you aware of any material difference between the Shelburne and the GM 60 in terms of parts/design?
They have the same heating specs and firebox size, and similar pricing when optioned in the same color. Which makes me think that the Shelburne is simply a dressed down GM60. However, the drafting specs for the GM 60 is .08-.15, the Shelburne is .06-1.0. That seems to be a substantial difference, especially in the higher range.

 

[tabner]

The bottom of the T is capped. There will be two 90 degree turns to the chimney, one into the wall, the other constituting the connection into the chimney.

Just curious, are you aware of any material difference between the Shelburne and the GM 60 in terms of parts/design?
They have the same heating specs and firebox size, and similar pricing when optioned in the same color. Which makes me think that the Shelburne is simply a dressed down GM60. However, the drafting specs for the GM 60 is .08-.15, the Shelburne is .06-1.0. That seems to be a substantial difference, especially in the higher range.

I'm not aware of any differences. I have only looked at Hearthstone's other models briefly in passing, never in-depth, so i cannot say for certain. But it seems to me that their three lines of stoves are basically the same fireboxes and burning technology, and then they just dress them differently. You can get full Soapstone, cast iron enamel like the shelburne, or the basic cast iron green mountain line. Not sure why the draft requirements would be different, i believe they're all reburn stoves with a catalyst added to the flue exit.
I just skimmed the shelburne manual quickly, and the internal diagrams of the bypass and cat locations, and the secondary air ports location, and the air intake control lever, all look identical to my green mountain.

 

[tabner]

is your chimney interior to the home, or exterior? Is the liner insulated?

Just speculation here, but perhaps the reason for the recent batch of GM complaints on here, vs the shelburne, is just timing? The GM is a very new line of stoves, i think it was the cheapest of Hearthstone's three lines, and with the new tax credits, a lot of people have been scooping them up. One person on here mentioned that their dealer claims to have installed over 80 GMs and only had one complaint. So we may just be seeing a small percentage of the new GM owners on here, having issues either getting used to the new stove Technology, or dry wood / insufficient chimney setup.
Whereas the Shelburne, I believe, has been around a lot longer, so dealers and owners are more familiar with their function.
Not sure, just thinking out loud.

 

[begreen]

Whereas the Shelburne, I believe, has been around a lot longer, so dealers and owners are more familiar with their function.
Not sure, just thinking out loud.

The Shelburne II is a redesign. The firebox design looks very similar to the GM60. The manual pictures of the bypass and interior look identical in several places.

 

[Simon Says]

is your chimney interior to the home, or exterior? Is the liner insulated?

Just speculation here, but perhaps the reason for the recent batch of GM complaints on here, vs the shelburne, is just timing? The GM is a very new line of stoves, i think it was the cheapest of Hearthstone's three lines, and with the new tax credits, a lot of people have been scooping them up. One person on here mentioned that their dealer claims to have installed over 80 GMs and only had one complaint. So we may just be seeing a small percentage of the new GM owners on here, having issues either getting used to the new stove Technology, or dry wood / insufficient chimney setup.
Whereas the Shelburne, I believe, has been around a lot longer, so dealers and owners are more familiar with their function.
Not sure, just thinking out loud.

Chimney is exterior. I do not believe it is insulated.

 

[tabner]

Chimney is exterior. I do not believe it is insulated.

Well give it a try and see what happens. But i think the general recommendation on this forum is going to be to Line it, and preferably to insulate it. Partly for stove performance, but mainly for safety/code compliance. If you do have problems with smoke out the door on reloads, adding an insulated liner will certainly help.

 

[neverstop]

Does anyone know what the baffle design update was, or should have been to remedy smoke rollout on door openings? Would they just have shortened the baffle or elevated the front of it? Right now the gap between the baffle and the air wash (or whatever is actually there) is about 1.5". The baffle isn't the most expensive thing in the world ($100 w/ shipping), I wonder how smoke rollout would improve if it was shortened by half an inch or more, or if you just shimmed the front of it? I'm guessing efficiency would probably take a slight hit?

 

[cabinwarmer]

Very interested here as are many about this new "baffle fix".

 

[neverstop]

Very interested here as are many about this new "baffle fix".

I reached out to Hearthstone, they didn't provide specifics but said the following:

smoke spillage is a symptom of poor draft, not the baffle. Both the Shelburne and the GM60 use the same baffle system. There was a slight change in the baffle, but the reason for the change was not due to smoke spillage. It was changed to accommodate the rear flue exit option that the Shelburne offers.​

So basically this is confirmation that the GM60/Shelburne share firebox designs and that the baffle change was only to accommodate the rear exit option of the shelburne.

Hi All:

I placed an order for a Green Mountain 60 recently. Delivery and install scheduled for early December. I thought I had done my research until I stumbled on this forum and the reported issues of back-puffing/smoking when the door is opened. I called the dealer to ask about the reports of smoking/back-puffing. I was told that Hearthstone came out with a recent update/change to the baffle that addressed the issue; that all their Green Mountain 60s in stock are less than a month old, and as such, they all include the change modification.

Can anyone opine on whether Hearthstone did modify the baffle recently to address the reported issue of smoking/back-puffing when the door is opened?

Something you might be interested in is the other correspondence that I received from them about draft. I know the GM60 isn't rear exit, but it also means top exit installations will probably require more height than other stoves. However, your chimney will definitely be above minimum requirements:

For rear exit connection, the recommended minimum chimney height is 19 feet (5.8m) off the floor or 16 feet 6 1/8 inches (5.2m) from the top of the stove.

 

[cabinwarmer]

Thanks !.......

 

[begreen]

The draft requirements listed in the manual for these stoves is notably higher than for the average stove. They are a good candidate for the >25' flue situation.

 

[Danknotts23]

I have another section of pipe I could extend our chimney with we are 15ft from the top of our stove and I thinking about doing that.
If I reload and shut the door there’s definitely some smoke happening but once the fire starts up it’s good. I had a 1979 Jotul 118 that isn’t picky about wood. So I’m going to need to split a ton of wood soon so it’s ready to go for next season. I have a buddy dropping off ash so I’m hoping that will be dry enough for next season.

 

[Danknotts23]

That’s a pretty tall chimney, should draft well. Make sure the 8 feet going down into the basement with the T is sealed well, you don’t want the bottom of the liner sucking cold air in from the basement, and detracting from your draft.
My GM60 is running right now. Works great. I took a video last night of the secondaries firing, every single hole on the secondary air ports was firing, pretty cool. I’ve also closed it down tight and had the glowing cats with no visible flames, like a true cat stove.
The only problem I have had with it is just smoke out the door on reloads - but some percentage of this issue (probably a large percentage) is me learning /experimenting when to do reloads. I need to get better at that.
This is why I’m curious about some baffle measurements when you get your stove. If it is a slightly smaller baffle for this reason, it might be something I wanna try.

Are you able to post the video you took?

 

[tabner]

Will this play? I think this forum is a little finicky about video uploads.

 

[neverstop]

Will this play? I think this forum is a little finicky about video uploads.
View attachment 286299

No this is just audio I believe. You can upload to YouTube, make the video restricted and then embed it here

Edit: I downloaded it and it worked

 

[Danknotts23]

Will this play? I think this forum is a little finicky about video uploads.
View attachment 286299

Very nice! I was able to play it!

 

[begreen]

Trippy flames, very nice.

 

[Simon Says]

I reached out to Hearthstone, they didn't provide specifics but said the following:

So basically this is confirmation that the GM60/Shelburne share firebox designs and that the baffle change was only to accommodate the rear exit option of the shelburne.



Something you might be interested in is the other correspondence that I received from them about draft. I know the GM60 isn't rear exit, but it also means top exit installations will probably require more height than other stoves. However, your chimney will definitely be above minimum requirements:

Thanks for reaching out to Hearthstone. Given that the firebox between the GM60 and Shelburne are virtually identical. Is it reasonable to conclude that the difference in drafting specs is due to the slight modification to accommodate the rear exhaust for the Shelburne?

 

[neverstop]

Thanks for reaching out to Hearthstone. Given that the firebox between the GM60 and Shelburne are virtually identical. Is it reasonable to conclude that the difference in drafting specs is due to the slight modification to accommodate the rear exhaust for the Shelburne?

Someone more experienced would have to give an opinion here.

 

[Lbk]

hello
I have been combing this blog for days.
we purchased a Mountain 60 wood stove last February. First Catalytic stove after our small Jotul F 100
We doubled our house surface and are now heating about 1200 Sq.ft. thus the need for larger stove.
We fell in love with the looks of the mountain 60, BUT when we tried it at home, we were not getting the fire feeling we were used to with our smaller Jotul.
Our wood is not ideal and thats going to be a constant factor. We live in the east Kootenays BC Canada at almost 3000 ft of altitude and collect our wood in the forest during summer.
It seems that we are having a hard time to really get the stove heat up to its ideal temp. so as to keep the glass and inner soap stone clean. I'm guessing that the catalyst must also not like this so much. (probably due to humidity of wood)
Although this stove is hybrid (cat off, it has a secondary burn system) our fires have often been smothered down but most important for us, and this is my main question, this stove seems to put out less direct heat than a cast iron or steel stove would. We have been visiting many friends this winter with basic stoves and walking in the room, you would just feel that toaster feeling emanating from the fireplace. I love that and I think that the soap stone lowers that effect. Probably why it is written on the hearthstone website that their stoves give off a more "comfortable" heat.
We are considering switching to another stove maybe a jotul, but just want to make sure about the difference of heat out put.
I'm still wondering if we are not using the Mountain 60 to its full potential because our seller was saying that it also gives off this primal heat as non-catalytic stoves do. But we have not really experienced it. It feels more like a big radiator. Oh, and the air control when at its minimum is still too open to our liking, because one cannot cut off the air to a full load at night and just start it up in the morning again as we used to with the Jotul.

Hoping to hear back.

 

[begreen]

If you want a more radiant stove then the choices are slimmer now. Operationally, the F100 is quite different than the GM60. It's amazing that you got an overnight burn in that little stove. Unfortunately, the choices for new stoves are greatly reduced since 2020. Otherwise I would have directed you to the Jotul F400, Hampton H300, or Morso 3610. Now, the Drolet 2110 is the largest available. However, the GM60 should get plenty hot enough to heat the place and should have a good long burn. How tall is the flue system on the stove? Do you have a thermometer on the stovetop or on the stovepipe? If so, what temps are you seeing?

Marginally dry wood is going to provide marginal performance in a modern stove. Try running the stove with good dry wood and see how it performs then. One option would be to add about 50% dry construction 2x4 cut-offs to the fire and see if that improves things. If you collect your own wood, it would be good to get ahead for a couple of years. Is doug fir available? That will dry enough to burn from green if cut, split, and stacked (top-covered) in March/April. If that is not possible then gather enough so that you are a year ahead.