How Does Air Flow On A Hampton/Regency HI300?

[velvetfoot]

Can anyone enlighten me on how the air flows in and out of a Hampton HI300 insert?

I can't find out where the air comes in? I can see what appear to be steel box manifolds for the air tubes, window air wash, and startup air (dog house). I realize the draft control rod goes into a steel-enclosed area and I've seen pictures of the wedge into slot arrangement inside that area.

I just can't figure out where the air comes into the stove. There's probably some kind of intake into that draft control area, but I can't see it.

Thanks.

 

[velvetfoot]

I'd be particularly interested in how the air gets to the air tubes (secondary air).

 

[cableman]

Those manifolds have to be open on the bottom.
I believe the bottom of the stove has 3 layers of steel, the exterior the air chamber and then the bottom of the fire box.

 

[velvetfoot]

I've tried taping off most of the spaces (vents?) at the base, on the left and right , and it really doesn't seem to have much effect on the roaring secondaries.

 

[velvetfoot]

I poked around with my cheap bore scope in the space under the firebox, through the side holes. I managed to see that stepped air control, as seen in the smartstove blog, which is now defunct. I looked some towards the back but ran out of time. Lighting, resolution, directing probe, made it difficult.

Here is the picture that you posted:

 

[cableman]

Would be nice if the air control flap covered that whole stepped air opening but it doesnt when closed all the way.
Im burning some 21-22% splits, and notice it def isn't as violent.

Im thinking towards the back would be open on left and right to feed the back channels which would feed the top tubes. The front channels should feed the air wash.
All air should go through that stepped opening and then flows through all the rectangle slots on lower left and right.

 

[velvetfoot]

As I said, looking with my lame ass borescope, I couldn't find any additional openings that go to the firebox in that space between the firebox and bottom floor. It's not like lt would matter anyway, since there'd be no way to modify them without taking the out and cutting into it,

Last night, I covered all but one of the larger air slots, on the right and left (I didn't see any slots in the back). I think it made a difference. Things in general seemed a little less violent although those secondaries are still real strong.

I also saw lower temperature on the top of the stove, (I've been running without the cast room air deflector), and on the glass (IR thermometer on both). The stovetop still gets good and hot at peak, but not as much, and I kept the fan on low the whole time. These observations were after one burn, so take that with a grain of salt.

Maybe I'm onto something...maybe not.

 

[cableman]

You would have to get that scope to the air channel above the air flap, thats where there should be openings feeding the front and rear air pillars. I have poked a flex light in through the hole on right side where the air lever would be if it were on the right side, i was able to see the air flap from the top.

Aside from being able to fully cover that stepped hole, closing off some of those rectangle slots should allow less air in, but who nows!
May cause air to speed up through the other ones.

 

[velvetfoot]

Well, I think I know how to control the air intake.
Caveat: I don't know what I'm doing, don't necessarily do as I do, I'm ot responsible for your actions, etc.
I made a controller to turn the fan on high when the stove top (6" in front of flue outlet) reaches a set temp: I chose 750F for now.
I made a plate from sheet metal to move over the remaining air slot so that it's adjustable. I attached it with magnets. I took off the right cast grille for temporary easy access.
When the stove top temperature went over 750, on it's way to what seems to be its usual peak of 860, I closed that hole some and it helped a lot. Amazing how small it can get.
It's at 726 right now and secondaries are much less violent, things look nice.
It's cool under there, so there's no problem using your hand to move the plate.
It' an option that has the potential to make the stove much more controllable.
It'd be great if I could make it more 'together' looking though...that's next I guess.
Note that this is a setup with a new (replacement) insert, tight door seal, tall chimney, dry hard wood.