K4 fire keeps going out

tyscon · Post by **tyscon** » Wed. Nov. 14, 2018 6:02 pm

I installed a k4 keystoker about 4 weeks ago. It ran perfect up until the past week. The fire stayed lit even on those very warm days. Now that the temps have dropped outside the fire keeps going out. I bumped the feed rate up in hopes that would help and it did not. Any suggestions?

Post by **StokerDon** » Wed. Nov. 14, 2018 7:41 pm

What does the fire look like, does it look like it is feeding enough? You might have something stuck in the bottom of the hopper.

If it ran well in the warm temps, we can probably rule out timer problems or missing timer cycles while on the high limit.

Is it still maintaining a good draft?

-Don

tyscon · Post by **tyscon** » Wed. Nov. 14, 2018 8:10 pm

It has about 1-2” of ash at the end of the shoot and then about 6” of fire. The flame is several inches off the coal bed. It seems to be pushing coal just fine. It has me stumped

Post by **StokerDon** » Wed. Nov. 14, 2018 8:15 pm

That is perplexing. Is it still maintaining a good draft? Something might have happened to your chimney.

-Don

lzaharis · Post by **lzaharis** » Wed. Nov. 14, 2018 8:21 pm

AH yes;
What size coal are you burning? if you have 6 inches of coal burning that is too much you should have no more than 2-3 inches of coal burning at the most.

Did you lift the baffle plate off in front of the flue breech to see how much ash had parked there?
Keystoker made no mention of this in the owners manual of the baffle plate being removable when I purchased my KAA-4-1 three years ago.

You need to check and see how much ash is built up under the fire grate if the fire has been going out too as a lot of rice coal fines will pass through the air holes.

Set your hold fire timer pins to run with the following:

3 minutes at zero time

2 minutes at 7 minutes

3 minutes at 15 minutes

2 minutes at 22 minutes

DON'T FOOL with the timer too much; if you do it will wear out the timer motor prematurely

Start with 5 threads out, start your fire and then you should back it off to 6 threads and then 7 then 8 eventually to 9 threads out like mine and it works.

After that you will have 2 inches of ash, 2 inches of fire and 3 plus inches of unburned coal.

I leave my KAA-4-1 at summer operating temperatures 140 low 160 high with 190 as a dump zone temperature and it works fine with 225+ feet of 3/4" fin tube baseboard which I hate anyway but it works.

tyscon · Post by **tyscon** » Wed. Nov. 14, 2018 8:41 pm

I’m assuming it has good draft. The pipe is warm throughout it.

The timer that is on my boiler is an old Honeywell timer. Probably the original that came on my boiler. It doesn’t have pins to set.

I seem to think the fire is burning up the shoot too far, which is causing some burnt coal. Then when the fan turns off and the fire dies down it has a hard time burning that coal after the fan turns back on. A few cycles of that and the fire eventually goes out. Does that make sense?

McGiever · Post by **McGiever** » Wed. Nov. 14, 2018 9:04 pm

lzaharis wrote: ↑
Wed. Nov. 14, 2018 8:21 pm
AH yes;
What size coal are you burning? if you have 6 inches of coal burning that is too much you should have no more than 2-3 inches of coal burning at the most.

Did you lift the baffle plate off in front of the flue breech to see how much ash had parked there?
Keystoker made no mention of this in the owners manual of the baffle plate being removable when I purchased my KAA-4-1 three years ago.

You need to check and see how much ash is built up under the fire grate if the fire has been going out too as a lot of rice coal fines will pass through the air holes.

Set your hold fire timer pins to run with the following:

3 minutes at zero time

2 minutes at 7 minutes

3 minutes at 15 minutes

2 minutes at 22 minutes

DON'T FOOL with the timer too much; if you do it will wear out the timer motor prematurely

Start with 5 threads out, start your fire and then you should back it off to 6 threads and then 7 then 8 eventually to 9 threads out like mine and it works.

After that you will have 2 inches of ash, 2 inches of fire and 3 plus inches of unburned coal.

I leave my KAA-4-1 at summer operating temperatures 140 low 160 high with 190 as a dump zone temperature and it works fine with 225+ feet of 3/4" fin tube baseboard which I hate anyway but it works.

Leon, Don't think this is a KAA-4, but rather a KA-4, so not a "clone" of yours.

tyscon · Post by **tyscon** » Wed. Nov. 14, 2018 9:07 pm

I burn rice coal. What is a baffle plate and a flue breech? I’m new to the stoker boilers. I always had a hand fire Harmon boiler. Yes this is an older k4. It was build in 1983

McGiever · Post by **McGiever** » Wed. Nov. 14, 2018 9:11 pm

tyscon wrote: ↑
Wed. Nov. 14, 2018 9:07 pm
I burn rice coal. What is a baffle plate and a flue breech? I’m new to the stoker boilers. I always had a hand fire Harmon boiler. Yes this is an older k4. It was build in 1983

He thought you had same boiler and maybe you hated your baseboards like he has.

Post by **StokerDon** » Wed. Nov. 14, 2018 9:16 pm

lzaharis wrote: ↑
Wed. Nov. 14, 2018 8:21 pm
What size coal are you burning? if you have 6 inches of coal burning that is too much you should have no more than 2-3 inches of coal burning at the most.

If you only have 2-3 inches of burning coal at full fire your feed rate is set too low.

tyscon wrote: ↑
Wed. Nov. 14, 2018 8:41 pm
I’m assuming it has good draft. The pipe is warm throughout it.

You have to measure draft with a manometer, you can't feel it.

tyscon wrote: ↑
Wed. Nov. 14, 2018 8:41 pm
I seem to think the fire is burning up the shoot too far, which is causing some burnt coal. Then when the fan turns off and the fire dies down it has a hard time burning that coal after the fan turns back on. A few cycles of that and the fire eventually goes out. Does that make sense?

No it doesn't. The fire should always be migrating down the grate, not up it. This could also indicate a draft problem. If all of the combustion gas can't get out the chimney, it will try to go out the hopper, dragging the fire with it.

Please check your draft and your chimney.

-Don

tyscon · Post by **tyscon** » Wed. Nov. 14, 2018 9:18 pm

I will check it. Thanks don

McGiever · Post by **McGiever** » Wed. Nov. 14, 2018 9:41 pm

Leon had a good point of checking and cleaning out dust and coal fines from under the perforated grate. Check the grate holes while you can too.

You can sometimes go in for the dust and coal fines with a reduced vacuum hose size through the rear of the stoker blower to clean out under there.