Auf

[flyzone13]

For those using Air Under Fire, is it necessary to build a manifold to put under the firebox to help direct the air to the grates above or is just letting it dump air into the box sufficient?

[psparr]

Not necessary, but helps.

[Cjadamec]

I tried the manifold thing and wasn't happy with it I just let it dump in under the grate. I put a chunk of steel about 4 inches away from where the air gets blown in and it does a good job of making the air swirl around. The wide open setup seems to work way better.

[murferd]

I've had it both ways, manifold seems to put more air directly up through wood, more flame. Also less ashes when opening door

[NhShaun]

I just have mine coming in a 4 inch steel pipe on the back or the ash box parallel with the grates. Seems to help, but I've never tried anything different. I wondered if I should have put some sort of diverter to push the air up towards the grates instead of directly towards the ash door..

[Super Sapper]

As long as your ash door is tight and not leaking the air has no where to go but up. I have mine coming in the back also with no problems as long as you keep the grates covered with wood or coals. If an area is open above the grates is open most of the air will go there as there is less resistance. I have also started covering up the first 4 inches in front of the door and seems to help.

[maple flats]

Where it goes in under the grates, put a tin or other block so the air doesn't just mostly go straight up rather than thru the wood. That's especially important if the air enter under the door.