Secondary Air

[woodsHAM]

Have a Clayton 1600 that was in home my wife and I recently bought. I'm mixing soft coal in with my wood and trying to induce more secondary in an attempt to aid the coal to burn the volatiles off faster and just help things burn cleaner in general. As of now the only secondary control is the on the flap to the forced draft blower, which we never use the blower but leave the flap roughly 1/2 way open. The furnace has the outlets in the rear of firebox for the hot water coil kit, my thought was to attempt to use 3/4" pipe and make a secondary burn tube using the outlet on the outside of furnace for my air intake. I could control the air by using a 3/4 ball valve. I'm searched for another load/feed door which has a spin damper on it but have not found any and I hate to drill into existing door or butcher it up making a make shift damper to it. Any input would be appreciated.

 

[brenndatomu]

I was always told that all the combustion air needs to come from underneath with coal. I don't think secondary air will do much when burning coal...but wood, yes

 

[woodsHAM]

with hard coal anthracite,yes all your combustion air does need to come from underneath the bed. with soft coal it does initially then the secondary air helps to burn the volatiles out of the smoke that otherwise end up as soot or a giant smoke cloud out the chimney. that's what I'm trying to minimize since I mix soft coal in with my wood.

 

[laynes69]

I know Hitzer utilizes some secondary air for their coal stoves. The problem would be getting the right amount of air under the fire and the right amount above. The more you use up above, the less draft down below. If your burning both coal and wood together, it wouldn't hurt to have some.

 

[brenndatomu]

I mix soft coal in with my wood

Ahhh, I see, carry on then.
Use the search feature here, there are TONS of threads about adding secondary air to older stoves. Lots of great ideas and pics