Where does air flow into an Englander NC30?

[dboone]

When you adjust the air control on the bottom of the NC30 where does this air then flow into the stove? It seems like a very basic question, but I could not obviously tell by looking in the stove and could not find it anywhere in the manual.

Thank you

 

[SlyFerret]

One of the guys from Englander will hopefully answer this for you. I'm interested to know as well.

I don't know if the air wash is controlled by the primary lever or not. I know the air for the secondary tubes is fixed.

I know that the air lever controls the air that comes into the stove through the "zipper" (the little doghouse thing).

I think air also comes in through the opening that runs along the front of the stove to the left and right of the doghouse. I've noticed that if I get ash too deep in the front and it blocks that channel, the stove won't burn right.

-SF

 

[dboone]

Yes, I have also wondered whether ash could be blocking the air flow. It doesn't seep through the ash tray/ash tray cover does it?

 

[dboone]

I studied the setup a little closer and to me it appears the knob on the front has a long rod that runs under the stove and possibly into a box that brings the air in. This box has a round 3" fitting that might be for an OAK attachment. If this is all true it would appear that the air comes up from the bottom into the center floor of the stove and maybe through the cracks in the firebricks. That is at least my uneducated guess.

 

[cmonSTART]

Your airflow enters through that 3 inch round hole. Some of it follows its little path up to the air wash system above the door opening, that little crack. And some of it goes another way to the little doghouse in the bottom center of the door. Another inlet lets air in which goes to the secondary tubes.

 

[BrotherBart]

cmonSTART nailed it. Primary air comes in through the three inch tube in the back of the bottom of the firebox. It travels from there to a distribution manifold in the front of the stove where part of it travels up risers on each side of the front of the stove and is injected as air wash across the window. The rest of the primary air goes through the manifold below the window to the "doghouse" in the center front of the stove. The doghouse is the only air inlet in the lower front of the stove. The rest of the primary air comes down the glass and is deflected into the fire by the flat plate on either side of the doghouse.

Secondary air comes in through a hole in the same area as the primary inlet and is preheated as it goes up through that rectangular steel box you see in the middle of the back of the stove and then is distributed to the burn tubes by manifolds running front to back in the top of the firebox.

 

[dboone]

Thanks for the details of the air flow. I will have to study what you are saying tonight when I get home. Is the "dog house" the hole that goes into the ash tray? If not please explain what and where this is.

 

[BrotherBart]

It is the little thing that sticks up right in the middle of the front of the stove directly behind the door. Variously referred to as "doghouse", "dogbox", "zipper", "boost air" and "that damned thing at the front of the firebox".

 

[T Osborn]

There is a good diagram at (broken link removed to http://www.bartfireside.com/catnoncat.gif) that shows the air flow for cat and non-cat stoves. Should make things clearer. I've lurked here since last winter and have never heard of the doghouse terminology.

 

[BrotherBart]

Except for the fact that the air flows nothing like that in the stove he asked about.

 

[BrotherBart]

I've lurked here since last winter and have never heard of the doghouse terminology.

It is just a term a guy down at the factory used for it when I was there. Some non-cats have the hole farther down in the front of the manifold under the door.

Here is the one on the 30:

 

[cmonSTART]

woof!

 

[SlyFerret]

I think I've heard Mike call it a "zipper" before.

-SF

 

[stoveguy2esw]

you guys are awfully close to correct,

primary air comes in through the "camera box" in the back where the OAK would be connected, and follows that channel to the front , splits ,and wraps around the door opening and comes out at the top of the door opening. this air is your airwash air,

secondary air enters through another opening above this (rectangular) and travels the manifold and through the air tubes in the top below the baffle board.
third stage air (or zipper as i call it) comes into the channel below the doghouse (or zipper)right through the floor of the firebox, these 2 small openings are quite hard to find but are there,

the way the air balance settles, with the primary open (draft control out) the amount of air favors the primary and reduces a bit in the second and third stage air, as the primary is closed (remember the flue is still pulling the same amount of air) the balance shifts more toward the secondaries and third stage air , that is why the zipper and the secondaries become so active once into the long burn.

 

[nojo]

So the secondaries do not pull air from the OAK? If that is so, then why not through the oak? Sorta defeats some of the purpose right?

Do you have a side cutaway image to show the air flow?

 

[mayor mcheese]

I have been looking for an air flow diagram for the 30 too. Mainly because I have been raking coals forward and getting alot of ash all up in the front. She is still heating like a beast though.

 

[jcims]

So the secondaries do not pull air from the OAK? If that is so, then why not through the oak? Sorta defeats some of the purpose right?

Do you have a side cutaway image to show the air flow?

The thing i wonder about (in addition) is the pressure differential between the OAK supply for the primary and ambient air for the secondaries. After i hooked my DIY OAK up, i immediately noticed that the primary air control setting had to be cut in half to get the stove to run right...now i find myself fiddle farting with the last 1/4" of travel, with literally 1/8" changes making a difference in the burn. Last night i really noticed what Mike said, how the roles of the secondary tubes and the doghouse change as the primary air is cut down, and i actually had to increase the air to keep the temp under control.

Unless Mike says it's a bad idea, I think i'm going to build a little manifold to supply both the primary and secondary with with OAK, and let the dog house do what it does. I think i'm also going to experiment with a valve there, as it seems i need a little finer control than what i'm getting out of the lever. (That and i'm thinking about building a safety cutoff that can close the supply when the temp exceeds some value)

Great thread.