Enviro M55 flame seems good, but lots of black build-up

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BobsWood

New Member
Feb 20, 2022
4
BC Interior, Canada
Trying to figure out my new-to-me Enviro M55 insert here...

The flame I'm getting seems good and generally the stove seems to be running well, but I'm concerned about the amount of black (soot? creosote?) build-up on the door after a short period of time. It's mostly in the top corners, but inside the stove as well on the back plate. Starts getting really noticeable after 24 hours or so.

The one "problem" I've noticed is that the pellets tend to overflow out the sides of the burn box where they sit and smolder, or burn with a lazy flame sometimes. The agitator was also pushing out some unburned pellets to the ash pan on heat setting 4, but I've turned the feed trim down to 1 and with the heat set at level 3 or 2 it doesn't seem to happen quite as much, but it still does.

See the attached photo which is about 20 hours after a full clean of the stove (including the glass). Premium fuel setting, fir pellets, heat level 2-3.

PXL_20220221_004856748.jpg
 

BobsWood

New Member
Feb 20, 2022
4
BC Interior, Canada
Thanks - I've watched those videos, and my flame actually looks like the example of the good flame (when burning on heat level 3 or 4).

But... still I seem to have an awful lot of black build-up on the glass in a relatively short time. And the videos don't really address having a lazy flame on pellets burning on the edges of the burn pot, outside the fire grate.
 

vinny11950

Minister of Fire
May 17, 2010
1,788
Eastern Long Island, NY
The buildup on the door looks about normal. It varies depending on the quality of the pellets, how well your draft is and how tight the door gasket is. So check all these things first. But to me, the buildup looks normal.

For the unburnt pellets getting pushed out the burn pot, try the premium setting on the stove. That should make the agitator run less often (I think every 30 minutes on that setting), and give the pellets more time to burn up in the burn pot, instead of being pushed out.
 
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Reactions: johneh

BobsWood

New Member
Feb 20, 2022
4
BC Interior, Canada
Thanks. The draft was checked a few weeks ago, and the door seal seems good (although notice the dark areas around the seal - not sure if that's a problem?). Even though I'm using premium pellets, they look and feel dry, and I do run on the premium setting, I am starting to wonder if that is the problem.

Here's my door and inside, 48 hours after a complete clean out. (Burning at heat level 2, feed trim 1, air trim 3).

PXL_20220221_175923990.jpg


PXL_20220221_180021414.jpg
 

vinny11950

Minister of Fire
May 17, 2010
1,788
Eastern Long Island, NY
Do the dollar bill test:


Your door gasket on the side that swings open looks a little flat, which is close the ash buildup on the glass. But I could be wrong so do the test.

How old is the gasket?
 

johneh

Minister of Fire
Dec 19, 2009
4,375
Eastern Ontario
Here's my door and inside, 48 hours after a complete clean out. (Burning at heat level 2, feed trim 1, air trim 3).
Wish the door on my old ef3 looked that clean after 48 hours
That's my door after 24 hours on a low burn rate using premium hardwood pellets
 

kchace

New Member
Feb 20, 2021
55
Southern NH
Ok, I also have an M55 insert and I don’t believe you have enough air. The rear cast iron piece has way too much black on it. It should not look like that no matter how much you run unless you run at level 1 a lot. Keep in mind that the air trim is just that, a trim. For more coarse adjustments you need to move the air shutter on the left side behind the narrow panel. Judging from adjustments I’ve made to get rid of far less black on the rear cast iron piece, I would open it about an inch more than it is right now. I would also suggest running the stove at level 3 or 4 for an hour once in a while. I will also mention that its not as obvious with the M55 when the flame is slightly too lazy. I go by how much black is on the cast iron back plate and it seems to be a good indicator, but it does take time to run and see how it goes. Only a very small fringe of black should be on that plate and even then mostly only on the left side.

btw - a SMALL amount of lazy flames out the side are normal. It’s an artifact of the way the burn pot is designed to be able to deal with clinkers from corn. You cannot get rid of those.

The PATTERN of the ash buildup on your glass is exactly the same as mine, but it’s too dark as are the rest of the insides. This all points to needing more air.

Ken
 
Last edited:

BobsWood

New Member
Feb 20, 2022
4
BC Interior, Canada
Ok, I also have an M55 insert and I don’t believe you have enough air. The rear cast iron piece has way too much black on it. It should not look like that no matter how much you run unless you run at level 1 a lot. Keep in mind that the air trim is just that, a trim. For more coarse adjustments you need to move the air shutter on the left side behind the narrow panel. Judging from adjustments I’ve made to get rid of far less black on the rear cast iron piece, I would open it about an inch more than it is right now. I would also suggest running the stove at level 3 or 4 for an hour once in a while. I will also mention that its not as obvious with the M55 when the flame is slightly too lazy. I go by how much black is on the cast iron back plate and it seems to be a good indicator, but it does take time to run and see how it goes. Only a very small fringe of black should be on that plate and even then mostly only on the left side.

btw - a SMALL amount of lazy flames out the side are normal. It’s an artifact of the way the burn pot is designed to be able to deal with clinkers from corn. You cannot get rid of those.

Ken

Thanks for the info! I will give that a try.
 

kchace

New Member
Feb 20, 2021
55
Southern NH
Thanks - I've watched those videos, and my flame actually looks like the example of the good flame (when burning on heat level 3 or 4).

But... still I seem to have an awful lot of black build-up on the glass in a relatively short time. And the videos don't really address having a lazy flame on pellets burning on the edges of the burn pot, outside the fire grate.
During startup I get a few pellets pushed out of the pot, but you should never see that when running. The fact this happens at higher heat levels points strongly to not enough air. Lazy flames out of the left side and sometimes (but not as often) on the right are completely normal.

Ken