Buck stove shot gun control

[pgmr]

On our model 80, all three user adjustable air controls introduce air into the front of the stove. Left and right are the door air-wash inlets and the center is the bottom (or shotgun) inlet.

The angle steel with holes on the top of the firebox behind the catalyst chamber supplies pre-heated air to the catalyst and probably also to support secondary combustion within the firebox. This air supply is not adjustable. The air is routed through channel steel welded to the outside of the firebox (but inside the sheet metal shroud so it is normally not visible). One can see these secondary air channels by removing the sheet metal corner pieces at the front of the stove. Once removed, the channels are clearly seen running diagonally from the bottom front up to where the angle steel inside meets the side of the firebox.

When conditions are just right, jets of flame will be seen coming out of the angle steel holes, so it does indeed introduce quite a bit of air into the top of the firebox.

 

[Crank shaft]

I see, so the right control does exactly what the left control does?

 

[Woody Stover]

The 91 controls are a little different; Only a left slider for shotgun and right slider for air wash. It seemed that when I opened the right slider, I would get more flame from the middle of the load so I figured the channel was regulated. Unfortunately I have no way to check weather that is the case, since the house has sold and I no longer have access to the stove. Crank shaft said earlier that when he operated the right and left slider independently, it seemed that the right slider was feeding air further back, but that could have just been an anomaly for that particular load. He would have to experiment further. I bet you could introduce smoke, maybe an incense stick, to each of the air inlets when the stove was cold, and maybe figure it out that way...

 

[Crank shaft]

Yes and it still seems that way. When I open the left it seems to control the front, If I open the right it seems to feed deeper in. Maybe I'm just crazy.

 

[Crank shaft]

I can see exactly what pgmr is talking about. I just opened the door and I can see the channel. Kinda weird they would have 2 doors go to the same place and than put a shotgun hole there also. What's the deal with that?

 

[Woody Stover]

The angle steel with holes on the top of the firebox behind the catalyst chamber supplies pre-heated air to the catalyst and probably also to support secondary combustion within the firebox. This air supply is not adjustable. The air is routed through channel steel welded to the outside of the firebox (but inside the sheet metal shroud so it is normally not visible). One can see these secondary air channels by removing the sheet metal corner pieces at the front of the stove. Once removed, the channels are clearly seen running diagonally from the bottom front up to where the angle steel inside meets the side of the firebox.

Could you see where the air entered the diagonal air channels that supply the top V-channel, i.e. could you confirm that they weren't fed from the front and tied into a controlled air channel?
I had those angle plates off the 91 at one point, looking for a broken weld because I heard a loud pop come from the stove. Buck told me that was more likely a side of the box flexing as it changed temp, and thinking back, the noise did sound like that. Anyhow, I was looking for cracked welds and didn't take note of the diagonal channels at that time.

 

[Woody Stover]

Unfortunately, they didn't have an 80 on the floor in the shop here that carries Buck, or I could try to find out more...

 

[Crank shaft]

Sounds good Woody! Thanks.

 

[Crank shaft]

Ok, here's what I did this morning. I pulled the front panel off of the stove and put my finger in the slide holes. I could feel the chamber heading over to the center but not up. It just seem strange that when I open and close b the right one it seems to change the fire in the rear. But maybe it's just in my head lol

 

[pgmr]

Could you see where the air entered the diagonal air channels that supply the top V-channel, i.e. could you confirm that they weren't fed from the front and tied into a controlled air channel?

IIRC, the channel steel is simply open at the end that terminates near the bottom of each front corner. There is really no place else for air to get to that secondary angle steel. The left and right inlets feed the U-shaped duct that goes up either side and then over the door where it exits as a wash over the door to slow down the creosote formation on the window.

 

[Woody Stover]

IIRC, the channel steel is simply open at the end that terminates near the bottom of each front corner. There is really no place else for air to get to that secondary angle steel. The left and right inlets feed the U-shaped duct that goes up either side and then over the door where it exits as a wash over the door to slow down the creosote formation on the window.

I see, and Crank shaft's observations confirm that. I thought maybe the back air channel was controlled, since it seems redundant to have two sliders to just feed the air wash. On the 91, the air wash has a feed on both sides but is controlled by one slider rod which has two plates on it. Like I said, I wasn't thinking or I could have looked at the diagonal feeds for the top rear V-channel and seen if they were open at the bottom. It certainly seems that when I open up the air wash slider, the fire picks up further back in the box. You would think the opposite would happen; With the V-channel always open, as you closed off the air wash, the draft would be pulling more air through the unrestricted V-channel. As usual, I'm perplexed.

 

[pgmr]

You are correct, there IS more air drawn through the V-channel when the adjustable inlets are closed. Normally, though, most of that air short circuits directly to the catalyst and out the stove, rather than hitting the base of the fire as the other air supplies do. This can be seen when a very hot, active firebox has it's primary air quickly shut off - that's when the jets of flame can be seen coming from the V-channel.

 

[Crank shaft]

I am now convinced I have a peice of crap for a woodburner. There is no control of air or fire. I put 3 peices of wood in this thing and after.50 hour I'm at 1800 degrees. Shut off all of the air and it keeps on burning. I wouldn't fill this thing up with wood. Buck stove can stick thus thing where the sun never shines!

 

[Woody Stover]

There is no control of air or fire. I put 3 peices of wood in this thing and after.50 hour I'm at 1800 degrees.

Yeah, you don't want 1800 for too long or too often, or it can compromise the cat. Adjustments are needed to cut the air intake. Can you take some pics of the air holes and the cover plates, trying to show how much gap you have there? Maybe we can come up with a solution that will be easy to implement. Once you get more control over the air, you'll be in the driver's seat.

 

[Crank shaft]

I'll take some tomorrow night when this thing cools down. New unit and no support from Buck stove. Is there a better unit on the market?

 

[Woody Stover]

I like the engineering and the quality of the Bucks. I'm not sure why the air control issue has surfaced on your 80 and my 91...not all Buck owners have had this problem. I wish I would have figured out my situation sooner, but at least now I can help you get on track quicker. You've spent the money, and the stove will do well for you once we figure out how to tweak it. That should be pretty easy to do.
If you read the forums, you'll find that people have problems with just about any brand of stove you can name. Getting what is desired from a stove can require some work on the owner's part, since no two situations are alike and there are a lot of variables involved. I can understand your being upset; It's a lot of money to shell out, and there's a feeling that everything should work well from the start. But people spend a helluva lot more for a new car, and sometimes end up in the same boat. For any stove buyer unwilling to deal with situations that may arise, one solution is to walk over and turn on the furnace. But where's the fun in that?

 

[Crank shaft]

I know Woody, I'm just so mad right now. I have done everything I have learned on the forum. I have reread and reperformed the things I have learned. I have checked and rechecked the ash door gaskets. I took my finger and pushed the guides up for the air control doors. Nothing seems to help and Buck stove is no help at all. I think it may have some bad welds or something. Then when I think I have it burning at a controlled rate the damn fire goes out.

 

[begreen]

No dealer support?

 

[Crank shaft]

Nope, owner died and wife sold the store. No support from Buck either! Don't know what to do now.

 

[Crank shaft]

Can you guys with the model 80 feel air from the blower if you open the front door for the ash box? I just wonder if this is normal or is this feeding the fire through the primary doors.

 

[Woody Stover]

Can you guys with the model 80 feel air from the blower if you open the front door for the ash box? I just wonder if this is normal or is this feeding the fire through the primary doors.

The blower output should be into the stove jacket, then out the vents, if it's like the 91. I don't think air should blow out the bottom where you are describing.

 

[Crank shaft]

I wonder if that's what my problem is

 

[Crank shaft]

How does the blower come out?

 

[pgmr]

I can't answer the question about the ash door - it was such a pain to use that I simply filled it with ash and abandoned it in place. It's much easier to use a shovel and bucket, for me at least.

If all of the air inlet possibilities have been checked (the three user controlled inlets, the seal around the door is tight and the ash pan seal is intact), then you'll need to check the exhaust outlets for problems. Here are some of the possible problems with the exhaust system:

1) The bypass damper might not be sealing correctly. This is difficult to check while the stove is in use. You can drop the flame shield that hangs below the catalyst chamber and do a visual inspection. If you have a feeler gauge, you can also check around the perimeter of the bypass to make sure there are no large gaps.

On our stove, it's possible to push the damper in too far and run it up over a weld that will leave it elevated above the bypass hole.

2) The catalyst chamber might be loose, allowing air to get around it instead of through the cat. Snug up the nuts while the flame shield is off.

3) The catalyst itself might be damaged or the gasket around the catalyst might be damaged. Inspect while the flame shield is off.


There are also timing and wood issues to consider:

1) If you wait too long to close the damper or the air inlets, it can get away from you. These are not air-tight stoves that can be choked down. There are gaps around the air inlet plates as well as the secondary air inlets behind the catalyst that are always open. Once the catalyst goes active (I use 500°F on the catalyst probe thermometer), shut the bypass damper and start closing the air inlets. I also use a kitchen timer to remind myself to go back and check the stove every 10-15 minutes until it reaches equilibrium.

2) A load of small pieces of wood will burn much quicker and hotter than a load of bigger pieces. It seems counter-intuitive, but large loads usually don't burn as hot.

 

[Woody Stover]

Here are some blower pics:

These two pics show the blower and its rectangular outlet.


To the right of the ash pan housing, you can see part of the rectangular opening that the blower outlet fits into. I guess that if the blower outlet wasn't fully into that opening, air would be blown out the front with the ash pan door open. However, I don't see that affecting the burn much.


This pic shows where the blower air comes out after passing through the jacket. Two vents blow straight out the front, then there are two more vents that blow out diagonally, one above each bay window. Is this similar to the 80? Can you feel heated air blowing forcefully from the vents?