Classic Bay 1200 smoke issue, Please help

[hookthefish]

Kappel, Yes to all your questions. all look great and clean and less than dime size. Flame height after initial lighting is usually 1" to 3" from top of burn pot.

This is my exhaust set up...

 

[DBCOOPER]

Regardless of what the stove does, it shouldn't smoke out the auger.

What happens is that the pellets start smouldering instead of igniting, the whole inside of the stove fills with smoke and hot gasses and at some point it lights off.On my CB1200i this is exactly like flashover in a house fire. It will cause a temporary over pressure condition in the stove causing smoke to come out of every place on the stove that is not sealed. I have seen smoke blow 6 inches out of the airwash vents on the front of the stove. It only happens when there is a very short shut down period between cycles and there is ash/clinkers in the burn pot that slows down the lightoff of the pellets.

 

[hookthefish]

This past 2 week I have had a piece of tape over the air intake hole and it hasn't been flashing any more, lesser smoke build up in the stove and a little lesser smoke billowing out of the auger area.
I haven't had any clinkers or ash build up, it's been burning so amazingly clean. I Have a cup full of ash in my ash pan since then and I have never seen ash or clinkers in my burn pot.

 

[kappel15]

What happens is that the pellets start smouldering instead of igniting, the whole inside of the stove fills with smoke and hot gasses and at some point it lights off.On my CB1200i this is exactly like flashover in a house fire. It will cause a temporary over pressure condition in the stove causing smoke to come out of every place on the stove that is not sealed. I have seen smoke blow 6 inches out of the airwash vents on the front of the stove. It only happens when there is a very short shut down period between cycles and there is ash/clinkers in the burn pot that slows down the lightoff of the pellets.

Have you tried dumping the pot more often? Usually when the stove is still good and warm, it helps ignite the initial fuel faster. I have had smoke build up in mine and poof, but never have had smoke blow out anywhere. But then I have a straight out exhaust on the Sante Fe and dump the pot out 3 times a day. kap

 

[kappel15]

This past 2 week I have had a piece of tape over the air intake hole and it hasn't been flashing any more, lesser smoke build up in the stove and a little lesser smoke billowing out of the auger area.
I haven't had any clinkers or ash build up, it's been burning so amazingly clean. I Have a cup full of ash in my ash pan since then and I have never seen ash or clinkers in my burn pot.

I would still check the screws and change the gasket. kap

 

[kappel15]

Kappel, Yes to all your questions. all look great and clean and less than dime size. Flame height after initial lighting is usually 1" to 3" from top of burn pot.

This is my exhaust set up...

Should have plenty of natural draft. What is strange is that you said it has ran fine before now. If it hadn't, I would say maybe too much draft since you can cover oak outlet and it runs fine.

 

[hookthefish]

Some times the flame height would drop bellow the burn pot height for a minute or 2 but it's mostly 1-3 inches. My feed rate rod is opened all the way because if I close it more the flame height will stay below pot height.

When I took off my auger yesterday the rubber like gasket looked solid behind the auger mount but the Nylon bearing I couldn't tell if it was good or bad.

 

[hookthefish]

Well it ran fine last year when I had it in a different location and exhaust arrangement.

 

[DBCOOPER]

Have you tried dumping the pot more often? Usually when the stove is still good and warm, it helps ignite the initial fuel faster. I have had smoke build up in mine and poof, but never have had smoke blow out anywhere. But then I have a straight out exhaust on the Sante Fe and dump the pot out 3 times a day. kap

I really don't have the issue since I got rid of the Quad stat and got one that I could set the swing.

 

[kinsmanstoves]

Smoke will take the path of least resistance. With that said remember this is a forced draft system. I would tear apart and clean all the venting and exhaust path inside the stove.

Eric

 

[kappel15]

Well it ran fine last year when I had it in a different location and exhaust arrangement.

I am guessing different exhaust setup then, and would try dumping pot a few more times a day and see how it does since covering the oak return is helping. But I would try and let some thru to see how it does, so it doesn't try and draw it all from other areas of the stove. kap

 

[hookthefish]

Yep! This one is a hard puzzling one!
I just called Quad for the 3rd time about this and they were stumped and couldn't give advice since my stove is burning correctly and cleanly after lighting.
When I took it apart yesterday I had "less" than a 1/16 of residue in the stove walls, pipe and liner. Only had maybe 2 table spoons of ash behind the baffled shield, 1 tbs of ash in the back clean out and 2 cups of ash in the ash pan. This is after 2 weeks of burning since my last cleaning and 3 days since my last burn pot drop or bump.

I will try opening the bottom burn pot hatch more often but don't think it will do much since its burning supper clean.

I think at this point I will just order the auger gasket and nylon bearing to see if it makes a difference since they don't cost much.

 

[kappel15]

I think it is burning clean cause you have such draft with that setup for some reason. Helps when it is burning, but not for fire up. kap

 

[SmokeyTheBear]

Can a useless old critter join in here and ask where hookthefish moved his stove from and to?

Your vent system raises red flags for me but I'll stay silent for now.

 

[kappel15]

Well you opened the door, you might as well walk in. lol

 

[SmokeyTheBear]

Well you opened the door, you might as well walk in. lol

You sure?

What happens with a nice tall slice of cold air in a flue with enough restrictions at the bottom for a little tiny combustion blower which may or may not be running on high at start up to over come, same thing happens with a down sloping horizontal run, or in a choked down vent.?

Once the cold air gets evicted and replaced with some warm stuff the draft is up to snuff.

 

[kappel15]

True that. But the issue is the over abundance of smoke at start up from a smoldering start up. I'm not there to see the smoke, but it shouldn't smoke that much, on start up, even with his exhaust configuration, esp. with him choking off the oak opening, unless something else is amiss. My question on his exhaust setup is does the 4" go thru the cap, or is he just stopping short of it and hoping it will draft ?

 

[SmokeyTheBear]

True that. But the issue is the over abundance of smoke at start up from a smoldering start up. I'm not there to see the smoke, but it shouldn't smoke that much, on start up, even with his exhaust configuration

The smoke can't get out the vent which is where it should go, if there is an over abundance of smoke it is simply due to the smoke not exiting as soon as it would which is frequently the only reason someone notices the smoke produced at start up. The smoldering is because the draft isn't there soon enough and therefore impeding the air flow past the ingnitor causing a slow ignition, it is all for the same reason.

ETA: In a word airflow.

 

[kappel15]

This too is possible, but not being there to see for sure leaves it all hanging also. There is smoke, and then there is smoke. Only sure thing is his exhaust is the only thing different to cause this. Does remind me of my wood furnace years back. Had a new chimney installed, square block with tile liner. The guy put some flat block near bottom to narrow tile opening. He thought this would create more draft. It didn't and he had to come back and remove them. kap

 

[SmokeyTheBear]

kap,

I've seen this situation in action on pellet stoves, in fireplaces, and with an oil fired hot water system.

On pellet stoves it can be caused by dirt in the works or vent back pressure.

A frequent situation is like the one DBCOOPER described namely a very smokey and delayed noisy ignition.

I once watched a flue plug get ejected from a chimney that was venting a hot water system. I didn't want to see what went on in that firebox.

It is also the reason that you are cautioned not to use too large a cross sectional vent.

And I do not believe that there are many pellet eaters that have a truly sealed hopper but then again I might be wrong.

ETA: I'll now go silent having given my off the cuff diagnoses of a likely cause.

 

[kappel15]

Only thing I'm concerned about is smoke coming out the auger shaft. That can be dangerous. And the only thing sealing the hopper on most any pellet eater is the pellets in the auger shaft. lol Bixby used a ferris wheel feeder that had a leather flap over the opening. Next issue is whether he can fix his system, or has to go to something totally different, or live with it.. I have a Sante Fe that has exhaust straight out the wall. I have had rolling smoke in it, and it was caused by a dirty pot, too much fuel, slow start due to too lean a mix. And I am not doubting your knowledge of exhaust systems. Just trying to cover all the bases. kap

 

[SmokeyTheBear]

Replace the bushing/bearing but unless those are really close tolerance replacements and even then there will be the chance they will leak, the only thing that keeps most smoke from showing up is the air pressure difference which is supposed to be such that it makes the smoke go up flue, even a dirty stove with a warm flue is enough to draw the smoke up the flue unless there is a negative air situation in the vicinity of the stove, in this case it can and will exit air washes, hoppers, and the augur assemblies That was the reason I wanted to know the from and too.

Ain't airflow wonderful?.

 

[kappel15]

Always is. Esp. when the power goes out and there is no natural draft. lol I have a guy that has that horizontal angled down a bit exhaust, but doesn't get any smoke on start up. It is hard enough to try diagnose a stove over the internet, esp. when you are not looking over the shoulder of owner to see if he did it, or did it right, what he posts. kap

 

[SmokeyTheBear]

Always is. Esp. when the power goes out and there is no natural draft. lol I have a guy that has that horizontal angled down a bit exhaust, but doesn't get any smoke on start up. It is hard enough to try diagnose a stove over the internet, esp. when you are not looking over the shoulder of owner to see if he did it, or did it right, what he posts. kap

Yes I know that it is hard to do this without being there, but I've done various things that way for decades so I tend to trust what I'm being told until that information conflicts with what I know. So far everything here makes sense to me.

That is why you want some natural draft or at least something that causes the smoke to exit the vent but it doesn't take much to foul that up and the next thing you know it is in the room with the stove. A simple clothes dryer, range vent, a few bathroom fans, or even being on the lower floors of a building.

 

[kinsmanstoves]

A puff of smoke out a hole that is less than a 1/8" is a worry to you? Remember unless the exhaust is blocked, the stove is under negative pressure, it will pull room air into the stove, not push it out, except from the exhaust.

Eric