How to limit sparks out of the stack?

[Mark-NH]

A fellow sugarer in our town has a sugarhouse right next to a busy road. Whenever they boil at night someone inevitably reports a fire because of the sparks coming out of their stack. This results in a mandatory visit from either the police or fire department. They have tried screens but have had no success with that. It is an airtight arch with a blower. Anyone out there have any ideas? Thank you

[maple flats]

Install AOF, it will burn everything before the exhaust exits the stack. Note, I said exhaust, not smoke, because once going good, there will be no smoke.

[wnybassman]

Mine looks like a Roman Candle as well. The sparks only fly a couple feet or so before withering out, but it still kinda scares the crap out of me at night.

[adk1]

Call the fire department before each boil

[mellondome]

When I burned wood, and before I added AOF, night boiling was always a good firework show. After adding the AOF, no more show.

[adk1]

I do not have a solid front door would air over fire even work for me? I have air under fire which works awesome

[psparr]

Adk you need a better auto correct program.

[adk1]

Yeah maybe I should just turn it on first haha

[mellondome]

Air over will still work without a solid door.

[maple flats]

My arch has double front doors with a space between them and my AOF/AUF work great. When I first put the AOF/AUF in I shut the blower off to add wood, but then 1 time my grandson forgot to shut it off and I noticed there was no sparks/smoke/ashes coming out he open door. Since then it is started as soon as the fire is burning enough to not blow out by the high pressure air, and it is run until almost all the coals are burned out at shut down. You do not need airtight doors, the AOF will work great without it too. However, insulated airtight doors would likely add even more efficiency.

[GeneralStark]

Even with AOF you will still get some sparks out the stack. This is why commercial forced air rigs are fit with spark arrestors, but even then they merely catch the large coals that may go up the stack when the AUF is wide open.

With my rig I generally only get sparks when I have the AUF cranked to get through a draw-off before reloading wood.

I know a local producer that is next to a trailer community and they had to switch to oil due to the concern related to sparks on the roof tops.

[Tigermaple]

Stupid question warning, what is and AOF?

[BAP]

AOF= Air Over Fire
AUF= Air Under Fire

[Drew Pond Maple]

had to switch to oil due to the concern related to sparks on the roof tops.
This is exactly why I had to switch to oil. Neighbors house is close to my sugar shack and they were real concerned about the sparks coming from the stack, and so was I. I figured it would cost more to build a new shack, so I went oil.