Maximizing Efficiency of Your Hand Fed Appliance

rberq wrote:That sounds promising. Do you have a long handled wire brush?

Yeah, handle is about 16 inches long with 4 inches of wire brush at a 90 degree angle to the handle which makes it easy to scour inside the firebox. I brush off the water coils once a day. I brush the inside of the fire box and baffles once a week.

rberq wrote:I will have to re-do my stove pipes next fall, and I'm thinking of putting the baro further away from the stove so I will have a couple feet more of hot radiating pipe.

That sounds like an excellent idea. Extract more heat before the baro mixes in cooler air

Boots wrote:i have no control over my primary air. it is a natural draft boiler. I just have a flap with a small hole in it attached to an actuator that opens for high fire. I just recently started running with over fire air. i started at 1 full turn open then i went to 3\4 turn then to 1/2 turn. apparently that was too little over fire air because i got a call at work from my mother- in- law, " i just heard a big boom from the basement". Everything was fine but i went back to 1 turn open for a couple of days just to make sure i corrected the issue. Tonight i put it back to 3\4 turn.

Yeah Boots, I'd say you are walking the fine line with your mix of over the fire air. I'm wondering though, if you really wanted to cut that over the fire air a little, what if your actuator opened 80% instead of all the way. Of course doing so may increase the time it takes for the boiler to get back up to temp, which might be OK if its a little over sized for what you are heating. Maybe that would solve the boom problem at 1/2 turn on your over fire air, and possibly give you more efficiency since less heat would be going up the chimney during idle periods. Its just a whim on my part since I'm not all that familiar with the operation of your boiler

I am just now getting to the stage where i want to start trying different things to improve either efficiency or ease of use. Me using over fire air was an attempt to eliminate the coal gas explosions i was having. Now i just have to find a point where i no longer have them and i am burning as efficiently as possible. changing my high fire actuator to not open the door so far is not a bad idea, my boiler seems to stay on low fire most of the time any way.

I'd like to increase mass for collecting and storing heat. I've got a pretty large V shaped steel plate slide right above the fire that governs the exhaust path for the flue. What about putting a layer of firebricks on top of it? They wouldn't block the exhaust gasses or smoke (from wood when I burn it) and as long as I could still slide it back and forth for start up and charging I can only see it keeping more heat in the stove.

Thoughts?

mudnut wrote:I'd like to increase mass for collecting and storing heat. I've got a pretty large V shaped steel plate slide right above the fire that governs the exhaust path for the flue. What about putting a layer of firebricks on top of it? They wouldn't block the exhaust gasses or smoke (from wood when I burn it) and as long as I could still slide it back and forth for start up and charging I can only see it keeping more heat in the stove.

Thoughts?

The only place you want to keep heat in, is in the fire box and there the more you can keep heat in the better. A layer of ceramic felt or light weight insulating fire brick on the underside of that baffle facing the fire would reflect heat back to the fire and improve combustion for wood or coal. I have no idea how it would be attached though, perhaps with stainless steel wire. Increasing mass does no good in a coal stove because the fire is steady unlike a wood stove. Huge mass as in a masonry or tile wood stove allows short very hot clean fires with the large mass able to absorb the heat and give it off for many hours after the fire dies.

My burner is shaped like an A frame, comes to a point right above that shelf and the the air is forced around that A point so my thinking is that heat would still get used even though it's above the firebox as the air is forced over the area that the shelf sits under (no that's not confusing at all I attached a drawing to show what I mean, a little hard to see I know but the 45 degree angle at the back of the burner where the flue is is the A frame that I'm talking about.

That baffle is to direct hot flue gas to the top and sides before exiting. Adding mass might help a wood fire to radiate a bit longer as the added mass cooled down.

rberq wrote:

Lightning wrote:I've found that keeping the inside of the firebox clean by brushing ash off it once a week, greatly improves heat transfer from the fire to where I need it to be.

That sounds promising. Do you have a long handled wire brush?

Lightning wrote:Also see the thread by 63roundbadge, on attaching heat sinks to the stove
Anyone attach aluminum or steel heat sinks to your stove?

I'm back... thanks for bringing back my thread, HONESTLY I am so happy with the heatsinks I added! I figure everywhere I have them, I have 4 times the surface area to dissipate the heat, rather than just the flat surfaces of the stove. I added 2 muffin fans to the center of the heatsinks blowing lightly over them to just move some air (220 fans running on 115v), and when shooting the heatsinks with the infrared thermometer they vary by 50-70 degrees where the heat has been removed. Also by slowly turning, fan noise is negligible.

I can't wait till the weekend to brush the insides of the firebox, as I have some insulating scale/ash on the surfaces and this post has confirmed that anything insulating bare metal is doing just that! Also, my next shake I will leave the ash pan out afterward. I'm a firm believer in soaking the steel with heat, any heat below the chimney is heat in the room.

63roundbadge wrote:I can't wait till the weekend to brush the insides of the firebox, as I have some insulating scale/ash on the surfaces and this post has confirmed that anything insulating bare metal is doing just that! Also, my next shake I will leave the ash pan out afterward. I'm a firm believer in soaking the steel with heat, any heat below the chimney is heat in the room.

Awesome
Nice job increasing the surface area for heat transfer with the heat sinks on your stove,
you are definitely getting more heat in your room with them

Just catching up on some reading and noticed this article.I have a fc700 and my book told me to leave the ash pan out for better air circulation to keep the grates cooler!

Yes, very important not to let ash pile up in the ash pan. It will insulate the grates from the cooling effect of the fresh combustion air coming in. This scenario will cause warped grates.

But don't confuse that with the heat radiation cascading down thru the grates. That infrared radiation is like the Sun, and the floor of the ash pan area is soaking it up. About 30 seconds of your hand in there and your skin would start to bubble up.

Lightning wrote:But don't confuse that with the heat radiation cascading down thru the grates. That infrared radiation is like the Sun, and the floor of the ash pan area is soaking it up. About 30 seconds of your hand in there and your skin would start to bubble up.

Shaw, I'll take your word for that, feel no need to prove it for myself

I left the ash pan out tonight post-shake, seems the floor of the stove never gets above 90 degrees, the incoming air cools and negates the heat radiated downward. I shoulda known this would happen because the ash pan is never more than warm to the touch.

I sacrificed our barbecue grill cleaning brush to clean the inside surface of the firebox, only a couple thousandths of coating removed, kinda negligent as far as insulating the steel?

I LOVE MY ALASKA KODIAK!

63roundbadge wrote:I left the ash pan out tonight post-shake, seems the floor of the stove never gets above 90 degrees, the incoming air cools and negates the heat radiated downward. I shoulda known this would happen because the ash pan is never more than warm to the touch.

Wow, I handle my ash pan with welder's gloves on and even then I have to hurry to set it down because the heat starts to burn my fingers

63roundbadge wrote:I sacrificed our barbecue grill cleaning brush to clean the inside surface of the firebox, only a couple thousandths of coating removed, kinda negligent as far as insulating the steel?

When I brush my firebox out it seems to have a layer of fly ash at least 1/16 to an 1/8 inch in places..
Its possible that with the differences in our appliances, you are having different results

I wouldn't dare stick my hand in there for very long

Lightning wrote:When I brush my firebox out it seems to have a layer of fly ash at least 1/16 to an 1/8 inch in places..
Its possible that with the differences in our appliances, you are having different results

Wow, I guess the stoves are different! That miniscule coating I have is after 4 years of use, I never scraped before. I do get 1/16 of ash on horizontal surfaces like the tops of the firebrick which I expect. The more I read on this great forum, the more I want to HUG my KODIAK. I must be really lucky with my setup, it really is easy to use and maintain. I will however wait until Spring to hug it, it would be as foolish as sticking my hand in the ash pit...

Did you ever think of toasting cheese sandwiches between shakings down there? I've seen a 'coal-fired' pizza place in Lehighton PA. Didn't last long though, maybe the thought of sulfur-aftertaste caused its demise?