Rotating Backward

Stoker Coal Boilers automatically feed the coal and have controls and pumps just like any conventions boiler. They are intended to be used as a primary heat and often have domestic hot water coils as an added bonus. They can be set up independently or in dual sytem with your existing oil/gas boiler. They can accommodate both hot water base board or steam plumbing.
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Rob R.
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Posts: 11348
Joined: Fri. Dec. 28, 2007 4:26 pm
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy
Location: Chazy, NY

Post Mon. Dec. 30, 2013 9:36 pm

Normy wrote:Thanks, so I changed it to the 40º spread as recommended. Also lowered the air to 4.5 with a 5 click as the recommend.
They really run nice on 5 clicks. Double check the ash ring the next time it runs hard coming out of setback...but it should be pretty close.

Normy
Member
Posts: 108
Joined: Sun. Sep. 21, 2008 6:44 pm
Coal Size/Type: rice
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: North East Corner of CT.

Post Sun. Jan. 05, 2014 12:03 pm

Rob R. wrote:
Normy wrote:Thanks, so I changed it to the 40º spread as recommended. Also lowered the air to 4.5 with a 5 click as the recommend.
They really run nice on 5 clicks. Double check the ash ring the next time it runs hard coming out of setback...but it should be pretty close.
We just experienced a couple days of sub-zero temps, the 520 just seems to run so much better when it's cold outside.

With now that the fan is running in the correct direction, there seems to be no need to raise the clicks over 5. The air I reduced to 4.5 as recommended in the EFM manual ( as a starting point), but I found that the amount of unburned coal appeared a bit more. So I raised the air up to 5.25 and reduced it quite a bit, (about the best I ever seen!).

Everything seems to be dialed in very nicely at the moment. So far so good.

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User avatar
Rob R.
Site Moderator
Posts: 11348
Joined: Fri. Dec. 28, 2007 4:26 pm
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy
Location: Chazy, NY

Post Sun. Jan. 05, 2014 12:26 pm

The ash ring is the most critical, I wouldn't worry about a few pieces of black kn the ash. Trying to eliminate them usually sends more heat up the stack than you save from the ash.

Normy
Member
Posts: 108
Joined: Sun. Sep. 21, 2008 6:44 pm
Coal Size/Type: rice
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: North East Corner of CT.

Post Mon. Jan. 06, 2014 10:54 pm

Rob R. wrote:The ash ring is the most critical, I wouldn't worry about a few pieces of black kn the ash. Trying to eliminate them usually sends more heat up the stack than you save from the ash.
Yes I agree as what I understand. The stack draft & over the fire draft are within the "acceptable ranges", st - .04 & ofd - .015. The ash ring is about 1.5 or 1.75 wide there about under full demand.

I think the decrease in unburned can be largely contributed to the air flow direction corrected. Also noticeable since correction is the center dark spot, reduced ash ring diameter to 1 to 2 inches, also much less clicker clumping in ash ring and ash bin. Of course this is coal from a different vendor, so I can't say if this is a factor.

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