Secondary Air Distribution System

 
User avatar
hotblast1357
Member
Posts: 5661
Joined: Mon. Mar. 10, 2014 10:06 pm
Location: Peasleeville NY
Stoker Coal Boiler: 1984 Eshland S260 coal gun
Coal Size/Type: Lehigh anthracite pea
Other Heating: air source heat pump, oil furnace

Post by hotblast1357 » Tue. Aug. 12, 2014 11:35 am

Lol no not yet, for the 5 dollars in extra pipe in goin to run it down the fire brick into the ash pan area first to see if it works lol its worth a shot


 
User avatar
Lightning
Site Moderator
Posts: 14669
Joined: Wed. Nov. 16, 2011 9:51 am
Location: Olean, NY
Stoker Coal Boiler: Modified AA 130
Coal Size/Type: Pea Size - Anthracite

Post by Lightning » Tue. Aug. 12, 2014 11:54 am

Just curious, how will ya get past the shelf that the grate frame sits on?

 
User avatar
hotblast1357
Member
Posts: 5661
Joined: Mon. Mar. 10, 2014 10:06 pm
Location: Peasleeville NY
Stoker Coal Boiler: 1984 Eshland S260 coal gun
Coal Size/Type: Lehigh anthracite pea
Other Heating: air source heat pump, oil furnace

Post by hotblast1357 » Tue. Aug. 12, 2014 3:59 pm

Well I went with 8 inch pipe goin down so it doesn't contact the shelve, and my baffle plates front and rear are on a angle, I'll snap some pics later

 
User avatar
Lightning
Site Moderator
Posts: 14669
Joined: Wed. Nov. 16, 2011 9:51 am
Location: Olean, NY
Stoker Coal Boiler: Modified AA 130
Coal Size/Type: Pea Size - Anthracite

Post by Lightning » Tue. Aug. 12, 2014 6:22 pm

Hmmm.. my hunch is that it might act as a bypass which is why we installed the fiberglass insulation to prevent.. But give her a try partner :)

 
User avatar
hotblast1357
Member
Posts: 5661
Joined: Mon. Mar. 10, 2014 10:06 pm
Location: Peasleeville NY
Stoker Coal Boiler: 1984 Eshland S260 coal gun
Coal Size/Type: Lehigh anthracite pea
Other Heating: air source heat pump, oil furnace

Post by hotblast1357 » Tue. Aug. 12, 2014 8:14 pm

Well wether its from underneath or above its a bypass

 
User avatar
Lightning
Site Moderator
Posts: 14669
Joined: Wed. Nov. 16, 2011 9:51 am
Location: Olean, NY
Stoker Coal Boiler: Modified AA 130
Coal Size/Type: Pea Size - Anthracite

Post by Lightning » Wed. Aug. 13, 2014 10:18 am

hotblast1357 wrote:Well wether its from underneath or above its a bypass
I've been thinking about how to answer this, here's what I've come up with..

Lets call this case #1 - A pipe that is bringing secondary air from under the grates to over the coal bed will need motivation. The motivation is pressure. It will be relying on the pressure difference between those two locations.. I measured the pressure above and below the coal bed to have a difference of .005" of WC with the negative pressure under the grates to be stronger. I took the measurements directly after a shake and load by inserting the mano probe in under the grates thru the primary air intake with the ash pan door closed.. I'm thinking the coal bed generates the extra -.005 just by its own mechanism of heating the incoming primary air and forcing it to rise as it flows up thru it. As the grate collects ash and slows air flow thru the coal bed this difference changes. It becomes equal, then further into the burn the negative pressure is stronger above the coal bed than under it.. Its at this point the pipe would begin to bypass the primary air meant for combustion and route it up over the coal bed.

Case #2 - Now if the secondary air is ported to the outside of the stove you have a pressure difference of -.03" WC or possibly more depending on how you have the baro set, up to -.05" WC.. So you see this pressure difference could be 6 to 10 times more than in case #1. And should (on paper) make a HUGE difference in the amount of secondary air getting in over the coal bed.

What I'm getting at is that the secondary system in case #1 will be totally dependent on the conditions inside the stove, mainly the coal bed - where in case #2 its completely independent and controllable. In case #1 there is implication that the pipe may take air from above the coal bed and route it back under the grates since negative pressure is stronger there right after a shake and load (and with the ash pan door closed) , making it run backwards :? then later in the burn cannibalize incoming primary combustion air.. It will depend on how much primary air is allowed to come in under the grate.

So, I realize this is all on paper lol and things that look good on paper don't always work in the field.. :lol: and I realize there is a lot going on there.. Some may read this and think it don't make any sense at all but the numbers have some merit and should dictate how case #1 behaves.. Try it and see what happens.. :)

 
User avatar
hotblast1357
Member
Posts: 5661
Joined: Mon. Mar. 10, 2014 10:06 pm
Location: Peasleeville NY
Stoker Coal Boiler: 1984 Eshland S260 coal gun
Coal Size/Type: Lehigh anthracite pea
Other Heating: air source heat pump, oil furnace

Post by hotblast1357 » Wed. Aug. 13, 2014 11:38 am

We will, and if it doesn't, well then we can say for sure to new people that it won't work,but for now I cannot find any evidence that it won't so its worth a shot for 10 $ spent


 
User avatar
Lightning
Site Moderator
Posts: 14669
Joined: Wed. Nov. 16, 2011 9:51 am
Location: Olean, NY
Stoker Coal Boiler: Modified AA 130
Coal Size/Type: Pea Size - Anthracite

Post by Lightning » Wed. Aug. 13, 2014 12:57 pm

hotblast1357 wrote:We will, and if it doesn't, well then we can say for sure to new people that it won't work,but for now I cannot find any evidence that it won't so its worth a shot for 10 $ spent
Sure enough! And will be an excellent addition to the thread.. :)

 
Jared43758
Member
Posts: 253
Joined: Wed. Apr. 16, 2014 8:40 pm
Hand Fed Coal Stove: Hotblast 1557
Coal Size/Type: Run of the mine

Post by Jared43758 » Sat. Aug. 30, 2014 8:19 pm

Lightning. Invent us a feed hopper!

 
User avatar
hotblast1357
Member
Posts: 5661
Joined: Mon. Mar. 10, 2014 10:06 pm
Location: Peasleeville NY
Stoker Coal Boiler: 1984 Eshland S260 coal gun
Coal Size/Type: Lehigh anthracite pea
Other Heating: air source heat pump, oil furnace

Post by hotblast1357 » Sat. Aug. 30, 2014 8:41 pm

Jared43758 wrote:Lightning. Invent us a feed hopper!
This would be a intense project! Awesome too have but idk if its possible

 
User avatar
Lightning
Site Moderator
Posts: 14669
Joined: Wed. Nov. 16, 2011 9:51 am
Location: Olean, NY
Stoker Coal Boiler: Modified AA 130
Coal Size/Type: Pea Size - Anthracite

Post by Lightning » Sat. Aug. 30, 2014 8:59 pm

Jared43758 wrote:Lightning. Invent us a feed hopper!
I'd have to do some research on hoppers lol..
Maybe it could be done. :)

 
User avatar
hotblast1357
Member
Posts: 5661
Joined: Mon. Mar. 10, 2014 10:06 pm
Location: Peasleeville NY
Stoker Coal Boiler: 1984 Eshland S260 coal gun
Coal Size/Type: Lehigh anthracite pea
Other Heating: air source heat pump, oil furnace

Post by hotblast1357 » Sat. Aug. 30, 2014 9:01 pm

I'm looking also lee, maybe this calls for a new thread..

 
Jared43758
Member
Posts: 253
Joined: Wed. Apr. 16, 2014 8:40 pm
Hand Fed Coal Stove: Hotblast 1557
Coal Size/Type: Run of the mine

Post by Jared43758 » Sat. Aug. 30, 2014 9:48 pm

Sweet guys.

 
Jared43758
Member
Posts: 253
Joined: Wed. Apr. 16, 2014 8:40 pm
Hand Fed Coal Stove: Hotblast 1557
Coal Size/Type: Run of the mine

Post by Jared43758 » Sun. Aug. 31, 2014 8:06 pm

Anything?

 
User avatar
hotblast1357
Member
Posts: 5661
Joined: Mon. Mar. 10, 2014 10:06 pm
Location: Peasleeville NY
Stoker Coal Boiler: 1984 Eshland S260 coal gun
Coal Size/Type: Lehigh anthracite pea
Other Heating: air source heat pump, oil furnace

Post by hotblast1357 » Sun. Aug. 31, 2014 8:22 pm

Haven't found anyone that has done it yet or anything close to it, its going to quite the mod, wold be easier if the hopper could enter the side of the stove due to ductwork exiting the top but idk if its possible to side/diagonal feed a stove


Post Reply

Return to “Hand Fired Coal Stoves & Furnaces Using Anthracite”