This picture of the circuit is drawn using a pictorial approach rather than using schematic symbols.

All the resistors are 1/4 watt, 5%, carbon film resistors. These are avaiable from Jameco or your local radio shack. You can buy just one from Radio Shack for about 25 cents each, Jameco sells them in batches of 100 but they only cost about a penny each.

Jameco part numbers

220K ----- 691420
47K ----- 691260
1K ----- 690865
1N4004 ---- 35991
LPT2023 ---- 112176
2N3906 ---- 38375
IRFZ24N ---- 669901
47ufd cap --- 609502
1000ufd cap - 607718

EDIT -- I corrected, rotated, and resized this picture, let me know if you can not see it well enough.

mechanical_parts_layout_type_schematic._-_2_X_3_JPG.JPG (49 Kb, 40 downloads)

Tim,

The barometric damper I used you can set it up vertical or horizontal .They fit in ths side of 6" flue pipe .You just have to cut a hole in the flue about 4 or 5 inches round and then install the damper over the hole and thats it .The whole install took me about 5 minutes. The coputer weight is adjustable so you can set it for a certain draft I set mine as sensitive as possible (2" of water column).

I picked mine up from the local Johnstone Supply . Icalled him this morning and he said he wouldnt have any problems shipping them out if you have problems finding them local Part# x71179 and cost is $27.58 plus shipping. You can reach him at 910-483-5517 his name is Tommy Wilkens.

quote:

Originally posted by johno:
I'd like to report on a successful modification to my old Sears shop heater ("pot" burner). Using a small punch as a lever, I angled all the air inlet holes to give it some swirl. This resulted in a swirling tornado-like flame, just like a Turk burner. There is no obvious change in the fuel consumption, but a dramatic reduction in deposits.

Hi John, I would like to see some pictures of this.

Thanks, Fred

I'll keep trying, but taking a picture of the inside of the burner when it's off doesn't show much that's useful. Trying to photgraph the flame doesn't work with the door open - it changes the draft and destroys the vortex.
A poor quality photo is at the bottom of Graydon's very useful site

One quart steep-sided SS dog food burner bowl test -- Looks like this is going to work out just fine, The flame burns smoother than it does in the smaller bowl and the light leafs of soot and ash blow out of this bowl during the burn just as well as they do for the smaller, smoother bowl. The coal is removable from the steep sided bowl just as easily as it is from the smoother bowl by slight chipping with a screwdriver, and there is no increase in the amount of coal produced.

E85-ethanol/diesel burner start-up fuel blend -- I mixed up another 2-liter bottle full of this 10% E85/90% diesel blend and let it set outside over night in below freezing temps, It seperated - but the E85-ethanol was not a clear liquid floating on top of the diesel, it was floating on top the diesel but it had sort of a pulpy orange juice look and consistancy. I took the bottle inside and let it warm up, don't know just what temp it was, almost room temp anyway. I shook the mix up and have kept it at room temps, it has stayed blended into one diesel-looking fluid for the last 3 days.

Well, I have spent the last 3 hours on-line trying to find the style of barometric damper that I need. Turns out I should have been searching for a "barometric draft control", once I used that as the search term I found just what I was looking for on good-ol-Ebay, and at a buy-it-now price of $15.00, it is even stainless steel rather than normal black flue pipe. Shipping cost more than the item but that is not unusual these days. The sale picture shows a pile of boxes so I suspect this seller will put up another sale as fast as they sell.

Just looked at the temps outside, 5 degrees F, no wonder I have burnt over 4 gallons of oil today through the homebuilt double-bowl veg burner in the inefficient converted wood stove here in my workshop place (that discussion is HERE). I think I will build another propane tank type sanders style heater to use here next winter, WAY more efficient.

picture_from_ebay.JPG (11 Kb, 33 downloads)

Tim,
Have you received your barometric damper yet?

Barometric draft control -- I have had this installed for a few days, it definitely does iron out the wind surges from the chimney. I am still experimenting with where to set the 3 different dampers for best burn.

To get the most heat from any specific amount of fire in the stove the manual flue damper wants to be closed as much as possible, to get the cleanest burn from the flame the manual combustion air damper wants to be set as wide open as possible, the automatic draft control effects both these other damper settings.

For my stove I need the barometric draft control set to about mid-range, setting it to the lightest setting causes it to stand about 1/4 open when the stove is burning, this is caused by the draft induced up the chimney from the stoves hot exhaust gasses. This setting reduces the chimney suction to such a low amount that I have to run the manual flue damper mostly open or the stove puffs smoke, because the flue damper is mostly open I have to close the combustion air intake damper way down or the fire blows out, both these damper conditions are absolutely the opposite of what is most ideal.

To get a baseline, I set the barometric combustion damper to it's heaviest setting, this kept it closed on all but the largest wind gusts, I then got the stove up to temp and burning in the same manner it had been BEFORE adding the automatic draft control. Once everything stabilized I then re-adjusted the automatic draft control to a point where it just stayed fully closed when the wind was calm, but swung open to correct for wind gusts. This setting allowed enough suction up the chimney that I could close the manual flue damper down to around 3/4 closed to hold heat in the stove, because the flue damper was restricting the flow of air through the stove I was then able to open up the combustion air damper considerably wider to get a cleaner burn.

Unfortunatly, I still get flameouts, not totally sure what is causing this yet, I think it is a combination of things still being learned. Upon inspecting my flame sensor unit I found that soot had almost clogged the sensor tube, the opening was only about 1/32 inch in diameter, this is likely why the stove has gone out some of the time, the opening was not letting the light from the flickering flame reach the optical sensor as well as it should. The soot is coming from the stove "puffing" smoke during cold startups, this always happens to some degree, a cold stove and burner just won't vaporize fuel as efficiently as when hot even though it is burning more volital startup fuel, they always "chuff" at least a few times before everything is up to temp. To try to reduce this sensor soot problem I am moving the sensor another inch away from the viewing hole in the side of the stove, hopefully this will be far enough to keep the puffs of smoke from getting to the sensor tube, time will tell. I will also now brush the senser unit off with a small natural bristle paint brush every now and then.

Part of the reason I am getting flameouts it that I am testing several differant burner bowl combinations, I am trying to get a cleaner burn than I have had from the original double-bowl insulated 3/4 quart mixing bowl burner. I ran this burner all last winter pretty reliably but it requires a pretty restricted combustion air damper to keep it from blowing out. Because of the restricted amount of combustion air it makes a bit of smoke and a good bit of soot, I have to scoop the soot out of the bottom of the stove every few days, there is enough soof flakes and light ash to fill the bottom of a paper grocery bag 2-3 inches deep, not a big problem but cleaner would be better. A cleaner burn is always more efficient and should also make more heat.

The picture here is of the original insulated burner unit that I used all last winter. The upper burner bowl is a 3/4 quart SS mixing bowl, The opening is 6 inches in diameter and the bowl is 1 7/8 inches deep. The lower insulating canister is one of a set of SS kithen containers from walmart, the sort of thing you keep flour and suger in. This perticular one is 5 1/4 inches in diameter and 5 1/8 inches tall. You can see that only the bottom of the burner bowl fits down inside the lowar canister, the next unit works much better at keeping the burner bowl hot as the entire burner bowl sets inside the lower canister.

original_3_quarter_quart_burner_bowl_burner_unit.JPG (17 Kb, 42 downloads)

This picture is of a burner unit that works much better. because the entire burner bowl is down inside the outer insulating canister the bottom of the burner bowl stays much hotter, this vaporizes the veg extremely well so MUCH LESS coal is produced in the bottom of the bowl, this burner also allows a LOT MORE combustion air to be used. The original 3/4 quart burner bowl combination would flame out if I opened the combustion air damper more than 1/4 of the way, this burner allows it to be opened to a bit over 1/2 way and It even burns with it completely open but I have had it flame out in that setting. With the combustion air set to a bit over half open this burner produces a very bright light-yellow flame, with no obvious orange color, the original 3/4 quart burner produced nothing but orange, even bordering on red. The yellow burn leaves very little coal in the bowl.

This burner bowl is a 1 quart SS dogfood bowl, it has much steeper sides and is a bit deeper than the original 3/4 quart burner bowl. Actual measurments are 6 3/8 inch in diameter and 2 1/4 inch deep. The insulating lower canister is the next larger one in the set and measures 5 7/8 inch OD and 5 inches tall.

1_qt_dogfood_bowl_burner_unit.JPG (44 Kb, 46 downloads)

This picture is a closeup of the tiny amount of coal produced in the 1 qt burner unit after burning for 8 hours.

amount_of_coal_in_1_qt_bowl_after_8_hr_burn.JPG (79 Kb, 44 downloads)

so where did you get the bowls thats awsome how clean it is...Tigman

Since moving from a 3/4 quart bowl to a 1 quart bowl worked so well I made the next step, a 2 quart burner.

This picture is of the burner that I am currently testing, Bigger has indeed proven to be better, this burner makes almost NO coal, burns with an even brighter and lighter yellow flame, and will burn with the combustion air damper completely open. I still get a few flameouts but some of that had to be the flame sensor, I will be testing one of a couple auto re-light ideas over the next few days.

This burner is made using a 2 quart SS dogfood bowl from the same series as the smaller one, it has the same steep sides that have proven to blow all the soot flakes and ash out of the burner. This burner bowl has an OD of 8 1/4 inches and is 2 7/8 inches deep. The outer insulating bowl is a 3 quart Walmart SS mixing bowl. Lukily the two bowls nest together nicely. The outer bowl has an OD of 9 1/8 inch and is 4 1/4 inch deep.

2_qt_bowl_in_3_qt_bowl_-_quartwr_up_view.JPG (34 Kb, 48 downloads)

This is a side view showing the shape of each bowl and of how the two bowls fit together

2_and_3_qt_bowls_-_shape_-_side_view.JPG (58 Kb, 33 downloads)

This shows my first idea for a crude flameout re-light idea. I know from testing that when the burner flames out the flame sensor safty device runs for a few seconds before shutting down the fuel feed pump, this places at least one drop of fuel into the hot, but not burning, burner bowl, this vaporized fuel makes a cloud of flammable vapor in and above the burner bowl. I added 4 pieces of 22 guage SS wire so they protrude out into the flame. The idea is that these thin pieces of wire will stay red hot long enough to re-light the fuel vapor cloud, HOPE - HOPE, haven't even tried this at all yet, tonights test.

2_qt_burner_bowl_in_3_qt_bowl_-_with_SS_wire_reignighter_wires.JPG (78 Kb, 42 downloads)

This picture is a closeup of the burn residue left in the bottom of the 2 quart burner bowl after an 8 hour burn, absolutely NO COAL and only a small amount of thin soot residue, hard to beliave. There was also almost no soot flakes in the bottom of the stove. Extremely clean burn, now if I can just get it to stay lit.

This burner shows so much promise it will be worth the time to design a 12 volt electric spark re-light device if the hot wires don't do the trick. the stove will still have to be manually lit once when it is cold but I think an electric spark device, similar to what is used in a home oil burner, would work fine to re-light the oil vapor, it could be triggered to run for a few seconds whenever the flame sensor shuts down the fuel feed pump. once the burner re-lights the flame sensor would automatically turn the fuel pump back on, Things are looking up in drip-fed burner land.

coal_in_2_qt_burner_bowl_overview_after_8_hr_burn_-_closup_1_-_top_view.JPG (94 Kb, 38 downloads)

This picture shows the 3 different sized burner units tested so far.

(actually, I have tested 4, the tiny 1 pint dogfood bowl burner was a complete bust, burnt for about 4 hours then went out, when opening the stove I found a pint of tar in the bowl and also running down the side of the outer canister, no idea why it didn't burn well but at least it was in line with the other testing, smaller bowls burn worse, larger bowls burn better ?)

3_burner_bowl_units_with_sizes.JPG (40 Kb, 33 downloads)

Do you have stock in stainless....You should..great info I'm watching..seems like cheating when you hand out info...but We all know burn chamber size etc all will have an effect so your giving us a good Baseline THANK YOU

Bowls -- The dogfood burner bowls are availble in the pets section of every home improvement and farm store I have looked in, they all seem to be the same, very thin SS made in India. They are sold under many different lables but I suspect they all come from the same factory.

I think the thinness of the metal has a lot to do with the burn efficiency, gets very hot quickly. having the burner bowl insulated inside another container keeps the combustion air from cooling down the burner, all promoting very thorough fuel vaporization.

The outer canister/bowls are all from Walmart but I don't see the canisters there now, I picked up the largest 3 quart mixing bowl there earlier this week. the outer bowl does not need to be SS, the 1 quart dogfood bowl fits inside of a normal big canned-food can just fine. These cans are 7 inches tall rather than 5 so it placed the burner bowl a bit too close to my combustion air pipe, I tried it but the air volocity that close to the combustion airpipe outlet in my particular stove is too great, it blows the flame way too much and causes flameouts with any setting over about half-open of the air intake damper. freon tanks should be about right to hold the 2 quart burner bowl but I forgot to measure one earlier, use what ever can be found.

One note - All these tests are being done using what most folks would consider very little fuel. I just don't need that much heat for my small houses, these tests are burning around a half a pint, to maybe a pint, of veg/hour, even in the dead of winter with continuous temps below zero f I only burn maybe a quart an hour. -so- I SUSPECT this style burner will also burn far cleaner than a turk style burner even when being fed much more fuel but I have not tested it and am not likely to, just don't need that much heat.

Can i have 1 of your houses...they must really be tight...tigman