help for keystoker boiler owners

 
lzaharis
Member
Posts: 2187
Joined: Sun. Mar. 25, 2007 8:41 pm
Location: Ithaca, New York
Stoker Coal Boiler: Keystoker KAA-4-1 dual fuel boiler
Hand Fed Coal Boiler: former switzer CWW100-sold
Coal Size/Type: rice
Other Heating: kerosene for dual fuel Keystoker/unused

Post by lzaharis » Sat. Jan. 21, 2023 4:23 pm

I wanted to pass along to keystoker boiler owners what I have experimented with in the last 2 years of burning rice coal in my original kaa-4 hopper and the koker hopper I have now.

To begin with I placed 2 pieces of 2" by 12 " by 1/8" flat stock across the hoppers opening/draw point covering the left and right side leaving the center open. By doing this I have reduced the hoppers draw point opening by 4 inches in width.

The rice coal still fills the opening fully and spreads across the fire grate in a thinner layer and burns very well. I have been averaging 80 pounds per day of rice coal burned and I have very little rice coal spilling over the sides of the stoker.

I have found that the stoker motor is laboring much less as there is less rice coal weighing down on the pusher plate which is good.

The fire is burning very hot and quite often the Dwyer triple gauge is reading 190+ degrees Fahrenheit and dumping heat from the boiler into the single heating loop which is my dump zone.

I have also found that when the stoker and combustion blower are responding to a heat call the coal fire is roaring and the fire has its narrow band of burning coal and wide band of ash as it is burning as it is supposed to do.

I have found that the wet bagged coal Blashack Rice Coal dries out much more quickly in the hopper as well.

I have also found that during the warmer periods when we have had all the rain my Dwyer Mark II manometer has read 0 Hg.

I am sure that you can duplicate the same results with your keystoker boilers as well.

The K-6 and larger boilers equipped with the opening in the front of the hopper could use angle iron to duplicate the same results I have had and benefited from.


 
User avatar
oliver power
Member
Posts: 2906
Joined: Sun. Apr. 16, 2006 9:28 am
Location: Near Dansville, NY
Stoker Coal Boiler: KEYSTOKER Kaa-2
Hand Fed Coal Stove: Hitzer 50-93 & 30-95, Vigilant (pre-2310), D.S. 1600 Circulator, Hitzer 254

Post by oliver power » Mon. Jan. 23, 2023 7:26 am

If you were burning hot, and triggering dump zone often, in my experience with Kaa-2 is you have too much fire on the grate. You needed to back off the feed some, starting with one turn. You only need fire enough on the grate to heat your house. Now the trick to this is the idle fire. You need a hot enough idle fire to prevent lag time. In my case, as long as the outside temperature is cold, 3 groups of 4 pins does the trick, and the triple aquastat runs the boiler. That being said, when the outside temps start reaching 45* - 50*, the call for heat isn't there. This means that the small amount of coal being pushed on the grate may burn out before any fresh coal is pushed on to keep the fire going. No call for heat, the triple aquastat doesn't signal the stoker to push coal. So, when outside temps are approaching 45* - 50*, I have to add one timer pin to each group of 3, over riding the tripple aquastat. It's quite the balancing act. But once you get it figured out, it's smooth sailing, with minimal overshoots.

 
lzaharis
Member
Posts: 2187
Joined: Sun. Mar. 25, 2007 8:41 pm
Location: Ithaca, New York
Stoker Coal Boiler: Keystoker KAA-4-1 dual fuel boiler
Hand Fed Coal Boiler: former switzer CWW100-sold
Coal Size/Type: rice
Other Heating: kerosene for dual fuel Keystoker/unused

Post by lzaharis » Mon. Jan. 23, 2023 9:45 am

Hello and good morning Oliver Power,

You probably have more snow up yonder than I do now as I woke
up to 5 inches of the white stuff this morning.

I have never been able to find a happy medium with my stoker
and the timer and I have tried.

We changed out the ash buckets last night before going to bed
and I checked it this morning and I had one inch of ashes in the
4-gallon pail so I must be doing something right after a 9-hour burn.

 
User avatar
oliver power
Member
Posts: 2906
Joined: Sun. Apr. 16, 2006 9:28 am
Location: Near Dansville, NY
Stoker Coal Boiler: KEYSTOKER Kaa-2
Hand Fed Coal Stove: Hitzer 50-93 & 30-95, Vigilant (pre-2310), D.S. 1600 Circulator, Hitzer 254

Post by oliver power » Mon. Jan. 23, 2023 7:46 pm

lzaharis wrote:
Mon. Jan. 23, 2023 9:45 am
Hello and good morning Oliver Power,

You probably have more snow up yonder than I do now as I woke
up to 5 inches of the white stuff this morning.

I have never been able to find a happy medium with my stoker
and the timer and I have tried.

We changed out the ash buckets last night before going to bed
and I checked it this morning and I had one inch of ashes in the
4-gallon pail so I must be doing something right after a 9-hour burn.
One inch in the ash bucket sounds like you are doing something right for sure. I see you're running a Koker now. Did you give up on the boiler? I don't think we got 5" of snow.

 
lzaharis
Member
Posts: 2187
Joined: Sun. Mar. 25, 2007 8:41 pm
Location: Ithaca, New York
Stoker Coal Boiler: Keystoker KAA-4-1 dual fuel boiler
Hand Fed Coal Boiler: former switzer CWW100-sold
Coal Size/Type: rice
Other Heating: kerosene for dual fuel Keystoker/unused

Post by lzaharis » Tue. Jan. 24, 2023 10:30 am

Hello and good morning Oliver,

I still use the kaa-4-1 for heat during the heating season.

The Warners Stoves and Coal folks had a new koker hopper
that they used to replace the rotted out hopper k-4 hopper
the boiler came with that lasted for 7 heating seasons.

 
User avatar
Rob R.
Site Moderator
Posts: 17179
Joined: Fri. Dec. 28, 2007 4:26 pm
Location: Chazy, NY
Stoker Coal Boiler: EFM 520
Hand Fed Coal Stove: Chubby Jr

Post by Rob R. » Tue. Jan. 24, 2023 10:37 am

lzaharis wrote:
Sat. Jan. 21, 2023 4:23 pm

The K-6 and larger boilers equipped with the opening in the front of the hopper could use angle iron to duplicate the same results I have had and benefited from.
The larger units have a piece of flat stock across the throat that can be adjusted to control the fire depth. Does your stoker not have this feature?

 
User avatar
McGiever
Member
Posts: 10120
Joined: Sun. May. 02, 2010 11:26 pm
Location: Junction of PA-OH-WV
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hand Fed Coal Boiler: BUCKET A DAY water heater
Hand Fed Coal Stove: Warm Morning 414A
Coal Size/Type: PEA,NUT,STOVE /ANTHRACITE
Other Heating: Ground Source Heat Pump and some Solar

Post by McGiever » Tue. Jan. 24, 2023 10:46 am

Rob R. wrote:
Tue. Jan. 24, 2023 10:37 am
The larger units have a piece of flat stock across the throat that can be adjusted to control the fire depth. Does your stoker not have this feature?
Way different stoker design in his and all the smaller "AA" models. But yes, all the larger "A" models do have that across the throat.


 
User avatar
nepacoal
Member
Posts: 1477
Joined: Wed. Nov. 21, 2012 7:49 am
Location: Coal Country
Stoker Coal Boiler: Keystoker KAA-4 / "Kelly" and an EFM 520 at my in-laws
Hand Fed Coal Boiler: Harman SF-260 - retired
Coal Size/Type: Buck

Post by nepacoal » Tue. Jan. 24, 2023 10:57 am

McGiever wrote:
Tue. Jan. 24, 2023 10:46 am
Way different stoker design in his and all the smaller "AA" models. But yes, all the larger "A" models do have that across the throat.
There is a fixed plate installed there on the AA's. It provides the perfect amount of coal to use it per the manufacturer directions. I can't imagine why anyone would want to modify it, but to each their own.

 
lzaharis
Member
Posts: 2187
Joined: Sun. Mar. 25, 2007 8:41 pm
Location: Ithaca, New York
Stoker Coal Boiler: Keystoker KAA-4-1 dual fuel boiler
Hand Fed Coal Boiler: former switzer CWW100-sold
Coal Size/Type: rice
Other Heating: kerosene for dual fuel Keystoker/unused

Post by lzaharis » Tue. Jan. 24, 2023 7:16 pm

My kaa-4-1 does not have a fixed plate as the hopper is a fully open rectangular bottom draw design.
That is why I have placed the 2 pieces of flat stock across the throat opening reducing the hopper opening
width by 4 inches.
The modification works, save fuel, I have less ash to deal with and I still have the lower low limit and high
limit temperatures that is all that matters and that is why I mentioned it.

 
User avatar
Rob R.
Site Moderator
Posts: 17179
Joined: Fri. Dec. 28, 2007 4:26 pm
Location: Chazy, NY
Stoker Coal Boiler: EFM 520
Hand Fed Coal Stove: Chubby Jr

Post by Rob R. » Tue. Jan. 24, 2023 9:07 pm

Perhaps the guys that installed your boiler discarded the plate described by others.

 
User avatar
Retro_Origin
Member
Posts: 484
Joined: Sun. Feb. 21, 2021 7:46 pm
Location: Schuylkill county
Stoker Coal Boiler: AA130 (Keystoker KA6 offline)
Coal Size/Type: Pea

Post by Retro_Origin » Tue. Jan. 24, 2023 9:21 pm

lzaharis wrote:
Tue. Jan. 24, 2023 7:16 pm
My kaa-4-1 does not have a fixed plate as the hopper is a fully open rectangular bottom draw design.
That is why I have placed the 2 pieces of flat stock across the throat opening reducing the hopper opening
width by 4 inches.
The modification works, save fuel, I have less ash to deal with and I still have the lower low limit and high
limit temperatures that is all that matters and that is why I mentioned it.
Could you post a picture of this maybe? I'm really curious what this looks like, I don't understand how you can feed less coal and have your feed rate less and not have the bed on the grates be extremely shallow? Is it possible the stoker unit has a oversized/speed motor that forces you to do this? Without the plates in does the coal push over the sides or something?

To me this sounds like drastically modifying original design without any compensation... I'm not saying what you've done is impossible (because it obviously is possible) but rather there seems to be a missing piece of the puzzle... 1+2=3 but it seems your doing 1+1=3 ... what am I missing?

 
lzaharis
Member
Posts: 2187
Joined: Sun. Mar. 25, 2007 8:41 pm
Location: Ithaca, New York
Stoker Coal Boiler: Keystoker KAA-4-1 dual fuel boiler
Hand Fed Coal Boiler: former switzer CWW100-sold
Coal Size/Type: rice
Other Heating: kerosene for dual fuel Keystoker/unused

Post by lzaharis » Tue. Jan. 24, 2023 11:23 pm

Rob R. wrote:
Tue. Jan. 24, 2023 9:07 pm
Perhaps the guys that installed your boiler discarded the plate described by others.
=================================================================================
Nope, it never had one. The clowns I hired did not dispose of anything as I was there when they installed the hopper and stoker nor do the crappy keystoker drawings I have show one.

The kaa-2 and kaa- 4 have the same 3 fire bed stoker and I assume the same koker stoker motor and gearbox.

The kaa-2 hopper is smaller than the kaa-4 stokers hopper.

The hoppers for the Kaa-2 and kaa-4 have the same hopper throat width that has the slotted tabs of sheet metal on the floor of the hopper that are banged into place to rest on the stoker to increase the width of the opening.

I just used 2 pieces of 2" by 12" by 1/8" flat stock and decreased the width of the hopper by 4 inches and so far so good.

The rice coal in the hopper falls to the top of the stoker pusher plate then the pusher plate pushes the rice coal to the 3 burner wide fire bed to burn.

What is happening is that there is a smaller weight of coal in the rectangular column of coal sinking in the throat of the
hopper in total is entering the stoker rather than the full width and weight of coal falling to the pusher plate on the stoker.
The coal is still falling down through the draw point which is the reduced square area of the stoker.

The rice coal is still falling through but at a slow rate due to the small weight of coal dropping down into the stoker gradually fills in the entire void at a slower pace and is pushed by the pusher plate at the same pace but with less strain on the koker motor and gear box.

It works that is all I care about.

I candidly think that the increased hold fire time on my stoker and the modification of the hopper by reducing its size is beneficial for the keystoker owner based on my experience.

I wish I had done this 5 years ago as well as lining the floor of the firebox with full firebrick which is next on the list to hold in even more heat and burn even less coal.

 
User avatar
oliver power
Member
Posts: 2906
Joined: Sun. Apr. 16, 2006 9:28 am
Location: Near Dansville, NY
Stoker Coal Boiler: KEYSTOKER Kaa-2
Hand Fed Coal Stove: Hitzer 50-93 & 30-95, Vigilant (pre-2310), D.S. 1600 Circulator, Hitzer 254

Post by oliver power » Thu. Jan. 26, 2023 11:11 am

That is very interesting. Ya see, I opened up my hopper bottom all the way. So I have full weight pushing on top the pusher block. This bigger opening would also not plug as easily, should a chunk of wood or something work it's way to the bottom of the hopper. My feed is backed off quite a bit, so I guess the opening the coal falls through is still small, no matter the size of the hopper opening. So I'm kind of doing the same as you, only your pusher block is pushing on a narrow line of fresh coal with more feed, while my pusher block is pushing a full width of fresh coal using less feed. I can lay a piece of plate across my hopper opening to take weight off the pusher block, and may do that.
Two things come to mind here; 1.) My little Kaa-2 runs like a Swiss Clock. I believe I have it very fine tuned, and am very happy with the way it performs. 2.) You say you have one inch of ash in the ash bucket after 9-hour burn? That's pretty good. I'm in that ballpark as well. I have very little black in my ashes. Post a picture of your ashes. I'll do the same. Lets compare for curiosity sake.

 
Kungur
Member
Posts: 688
Joined: Thu. Sep. 25, 2008 7:09 am
Location: Chardon,Ohio

Post by Kungur » Thu. Jan. 26, 2023 3:06 pm

I must be really doing it wrong because I fill my ash pan almost to the top everyday

 
lzaharis
Member
Posts: 2187
Joined: Sun. Mar. 25, 2007 8:41 pm
Location: Ithaca, New York
Stoker Coal Boiler: Keystoker KAA-4-1 dual fuel boiler
Hand Fed Coal Boiler: former switzer CWW100-sold
Coal Size/Type: rice
Other Heating: kerosene for dual fuel Keystoker/unused

Post by lzaharis » Fri. Jan. 27, 2023 9:37 am

Kungur wrote:
Thu. Jan. 26, 2023 3:06 pm
I must be really doing it wrong because I fill my ash pan almost to the top everyday
======================================================================================

Hello Kungur,

If you wish you can set your 30 minute timer to run this way:

Zero to three minutes, seven to eleven minutes, fifteen to eighteen minutes, and finally twenty three to twenty seven minutes.

Set the pusher plate stroke at 12 threads out.

Set the High limit to 170 degrees Fahrenheit and the low limit to 150 degrees Fahrenheit leaving the differential at 10 degrees Fahrenheit.

I have had to lower the high and low limits by 10 degrees Fahrenheit during the warmer parts of the heating season.


It works and I find few if any unburned black rocks/slate in the ash.


Post Reply

Return to “Stoker Coal Boilers Using Anthracite (Hydronic & Steam)”