Green Mountain 40 - Primary Air Control blocked?

[Zivio]

Greetings!

We moved into a recently constructed home that has a new Green Mountain 40 installed. We do not know who installed it.

I've been having trouble lighting fires without keeping the door open and just discovered that there is a piece of metal mostly blocking the air intake on the bottom of the stove (see picture.) This doesn't seem correct as it blocks the intake area as though the primary air control is pushed all the way in. Moving the air control lever in or out doesn't have any effect on controlling the fire.

Should this metal be removed? If so, how? I don't see anything in the manual or installation instructions describing this.

 

[begreen]

That looks like the primary air control. Does it open and close when the control is slid in and out?

 

[Zivio]

Aha! The primary air control lever can be moved in and out, but this steel "blade" portion is completely disconnected from the lever and is jammed in place. Tried moving it with pliers but no go. I think I'll remove the lever (allen bolt) and see if I can access/budge it. Not sure how it was supposed to be connected to the lever in the first place (brazed/welded?) but maybe further experimentation will tell.

 

[vatmark]

Could that possibly be where the outside air kit attaches? Page 13 of manual.

https://1q4gfb42pami41tumh2vps5s-wpengine.netdna-ssl.com/wp-content/uploads/2020/12/hearthstone-gm40-8640-manual.pdf

 

[Zivio]

Could that possibly be where the outside air kit attaches? Page 13 of manual.

https://1q4gfb42pami41tumh2vps5s-wpengine.netdna-ssl.com/wp-content/uploads/2020/12/hearthstone-gm40-8640-manual.pdf

Yes, that's where the kit attaches. It is also the air intake for room air if you choose not to connect to outside air. The metal "obstruction" appears to be the actual primary air control "blade". It is jammed and not connected to the air control lever. I think it may have slipped off and when the bottom plate of the stove was screwed and sealed on, it got trapped.

Trying to work it out, but not sure how it will connect up to the control lever if and when I do get it out.

 

[Zivio]

Upon further study, seems to me maybe this is OK as is. There is about a 3/8" gap on one side of that steel blade pictured. The air control lever "plate" slides on top of that blade and will expose or cover the tiniest bit more or less of that 3/8" gap. Doesn't seem to me like that would be enough to make a difference in the amount of air admitted into the stove, but perhaps that's the way it is designed. I saw this guy on YouTube adjusting the air control on a different stove -- his control lever goes side to side to constrict or allow more air. Seems like his has a larger opening though.

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[Zivio]

I just now found another thread on this forum showing the same issue but with a Green Mountain 60. It wasn't completely definitive about that piece of metal blocking the intake, but some other people had a problem and tried removing it.

 

[tabner]

yes, in that old thread Labans actually had a GM40, and he did remove that little metal piece of flashing. If you scroll through the photos contained in that thread, there is one of just that piece of shiny/rusty flashing. Not sure how he got it off - if he had to remove the whole bottom shield/casing which is siliconed on or not. On one hand, it doesn't look to me like it should be there. on the other hand, it technically doesn't block the air flow since it is somewhat bent away from the air control and air can flow around/past/under it. You are now the second Gm40 with that piece, so maybe it is supposed to be there. Although Nigel says his Gm40 does not have it, and none of the GM60s seem to. Calling Hearthstone and emailing some photos might gain some insight.
have you used the stove at all? I'd see if it works correctly, before i started removing stuff.

 

[Zivio]

yes, in that old thread Labans actually had a GM40, and he did remove that little metal piece of flashing. If you scroll through the photos contained in that thread, there is one of just that piece of shiny/rusty flashing. Not sure how he got it off - if he had to remove the whole bottom shield/casing which is siliconed on or not. On one hand, it doesn't look to me like it should be there. on the other hand, it technically doesn't block the air flow since it is somewhat bent away from the air control and air can flow around/past/under it. You are now the second Gm40 with that piece, so maybe it is supposed to be there. Although Nigel says his Gm40 does not have it, and none of the GM60s seem to. Calling Hearthstone and emailing some photos might gain some insight.
have you used the stove at all? I'd see if it works correctly, before i started removing stuff.

Yes, I'm reluctant to remove anything. The stove will burn, however, is difficult to start without keeping the door open. And a note about the picture, while it looks like there is a substantial gap running vertically (in my picture) it is only the the smallest of gaps as seen in the bottom part (again, my picture) that is either expanded or constricted by the air control "paddle." Hearthstone no longer has a phone number for customer support -- the phone number listed in the previous thread I mentioned takes you to a recording. Only Hearthstone dealers have access to phone or online support. I did call an authorized dealer and sent them an email ... we'll see if I get any response.

 

[Rob_Red]

My GM 40 does not appear to have any bare pieces of sheet metal like yours. Below are pictures of both the air control closed and then open where you can see right into the air passage. Hope you figure it out, I am very happy with the performance of my stove.

 

[begreen]

Thanks for the pics, Rob. It looks the same as Zivio's, but somehow his got quite rusty. Not sure if that is causing it to stick, but he should be seeing that same action with the air control.

 

[Rob_Red]

Question for the OP, how dry is your wood? Lighting a newer EPA stove with high moisture wood will cause you to need to have the door open and will be a huge PITA

Also I highly recommend the top down start method, not only does it light easily but it’s get the CAT in the active range very quickly.

How long ago was it split and stacked?

 

[GM80NY]

As long as your air control moves in and out freely it doesn't sound like there is any issue. In my experience with the GM80 You can't light the initial kindling bundle without first keeping the door cracked and when the flames starts whooshing around you slowly crack it open (max 2 inches) until the whooshing stops after a minute or two you can close it and the fire should keep going. I have yet found a method to really get them rolling fast and with minimal loading. I'm in year two with it. Hope this helps.

 

[outdoorguy864]

So this is my second year on my GM40 and I use to always start the fire with the door just touching with being closed. However, when the door is closed I like how the air intake pushes the flame to the back and rolls up over the top. so my last 6 or so fires I have had better results starting the fire with the door COMPLETELY shut and air intake open. I prepare my own split kindling, use four of those typically, fire starter and as many small to medium splits I can fit in there.

I did double check and I don't have that little metal plate on the underside in the air intake.