Any Suggestions on Increasing Heat Output?

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rschoensta
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Post by rschoensta » Wed. Jan. 17, 2007 5:22 pm

Hi,
I bought my stove in late October.

(It's a pocono back vent with a 12" duct top.
The stove sits in my basement right below my living room in a separate furnace room. The hot air is ducted directly to my living room above using flexible insulated duct pipe with about a 12' run max.)
And now with 2.5 months experience there are some positives and negatives cropping up.
The positives are related to ease of use - at least relative to a wood stove.
The thermostat - i.e. the coal trol - works great.

With the large hopper I only have to tend the stove once a day - and even there I could probably stretch it to at least once every 2 days.
I'm averaging about 1.5 buckets of coal a day - or around 50lbs I estimate.

Emptying the ashes has been easy so far because there is no snow on the ground.
That will be more of a chore in the future.

The real issue and one I have been concerned about for sometime is overall efficiency and related to that overall output.

This stove is replacing a hot water oil boiler that was rated at 105,000 BTU input.
This kept my whole house warm at 70 degrees even in the coldest weather - which could be as low as -35 degrees at night.

Well last night we had -8 degrees and the temperature in the main room - which is where the heat comes directly from the stove in the basement below - was only 58 degrees. I have partially closed off 3 bedrooms that were previously heated.

I don't know if I can figure it like this but I will.
In -30 degree weather the prior furnace could heat the house to 70 degrees.
So lets figure that it was 70% efficient meaning the output was around 73,500 btu.
At -30 there is 100 degrees of temperature difference that needs to be overcome.
So figure that for each degree of temperature rise my house requires
735 btus.
At -8 and 58, the total rise in temperature is 66 degrees.
So if you multiply 66 x 735 you get only 48,510.
And when you figure that I'm not heating all my house, the output is less than that.
Now I have not started doing it yet, but it should be fairly easy to measure the amount of coal you put in a furnace by weight and the amount you take out in the form of ash.
And I would think this would be proportionally related to effciency.
My own guess is that I am taking out a lot more in ash than I should be.

I mentioned this early on, that there seemed to be a fair amount of unburned coal in the ashes and I still think that is the case.

I'm not exactly sure of my settings.
But I think the only change I have made with respect to the coal feed rate is to set the minimum up to 6 from four.

I have the barometric damper set at four.
In warmer weather this hardly opened but this morning it was open a good inch or two.

In cold weather like this the feed rate is almost always 99 per cent.

Any suggestions on how to increase output?
And for that matter what is the maximum output of a 90,000 BTU Pocono.

Rich

 
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coaledsweat
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Post by coaledsweat » Wed. Jan. 17, 2007 6:08 pm

Sounds like your heat is going up the chimney maybe?
Hold your hand close to the feed door, it should be throbbing with heat. Now repeat near the stove pipe, is it as warm or warmer?

 
rschoensta
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Post by rschoensta » Wed. Jan. 17, 2007 6:28 pm

No I don't think so.
I have a thermometer on the stove pipe.
I think the temp is only about 120 or so if that high.

I'll check the exact temperature tonight.

But I don't think that's too bad.

And when you say put your hand close to the feed door which door are you talking about.
Are you talking about the front door with the glass in it.
That is very hot when the stove is running full blast as it is.


 
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LsFarm
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Post by LsFarm » Wed. Jan. 17, 2007 6:35 pm

I've been playing with a couple of Leisure Line stoves to heat my shop. The units do not have the Coal-Trol unit, they have reostats to control the speed of the fans and stoker.

One thing I have noticed is that the stoker motor needs to be on high, turning down the fan, really reduces the heat from the bed of burning coals, and increases the amount of unburnt coal in the ash pan.

What I have really come to like is the effeciency of these stoker stoves. I get 250-450* temps on the stove body, usually measured just above the door or on the sides, but the temperature of the chimney pipe is rarely over 100*, usually less. There is virtually no heat being wasted!! And I'm heating my shop on very little coal a day.

Is there a full bed of hot coals burning on the stoker?? Are there 8-10" flames coming off the coals?? This is what you should see when the stove is near max heat output.

Leisurline reps will be here soon to help. I'm sure they can help with your stove.

Greg L

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Jerry & Karen
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Post by Jerry & Karen » Wed. Jan. 17, 2007 6:46 pm

Hi ,
With a 90,000 BTU Pocono you will see about 72,000 BTU's when at 99%. You say that you have a 12" duct top, so that means that your loosing all of the heat from the sides of the stove. If you want all the heat upstairs and very little in the basement then you should have a hot air jacket on the stove. We sell our stoves as supplement heat, not furnaces. I think if I were you I would inclose the stove with a jacket, take off the 2-265 cfm fans and put a 12" duct fan inline in your run. I would hook the duct fan up to the coal trol and let it do its work. I think you will see a big difference in the heat going upstairs. If you have a buddy that's a tin knocker play with the jacket idea. If not, then we sell them.
If you don't want to invest in a jacket then I would suggest that you install a duct fan in your 12" run, but if you do, take off the convection fans that come with the unit.
Jerry

 
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Post by Jerry & Karen » Wed. Jan. 17, 2007 7:12 pm

Hi Greg,
With the coal trol the combustion run wide open 24/7 so you always get a good clean burn. The combustion fan that we use is a 45 cfm fasco which is a little over kill. The reason we did away with the rheostat was because people would turn down the rheostat and let the feed rate up. This would make for a incomplete burn everytime and a real waste of coal. Before the coal trol we had an on/off switch, before that we had a rheostat.
Jerry

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