Not Enough Heat...

 
reckebecca
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Post by reckebecca » Sun. Jan. 18, 2009 8:15 pm

rewinder wrote:Congrats !!! I knew you'd sort it out with the help from everyone here. That stove looked like it was capable of performing better than you first reported.
Thanks. I could not have done it without you guys. I told my dealer a week or so ago that if it hadn't been for this forum that the stove would have been listed on Craigs List! :)

Of course, now that my living room is 85* and I'm in t-shirt and shorts I am trying to remember what I did NOT to get so much heat out of it! LOL

I can't thank you all enough for the generosity in sharing your knowledge.


 
reckebecca
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Post by reckebecca » Sun. Jan. 18, 2009 8:16 pm

Freddy wrote: I never noticed until right now that curve is one letter away from curse. Hmmmmmm
That's funny - I sure did feel cursed for a while there! Thanks to you all I was able to lift the spell. :)

 
CapeCoaler
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Post by CapeCoaler » Sun. Jan. 18, 2009 8:56 pm

Sounds like you have the thermo air damper open in the back with the air shut in the front, yes?
If this is the case then the reason you are overheating is the thermo air damper is set too high.
Lower the back air damper setting so it is closed then open your front air to just maintain the fire at what room temp you like say 75*.
When the room is 75* the back air should be closed tight and the front open to the amount to maintain 75*.
The back will open and close as the room temps drop and then rise.

 
rberq
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Post by rberq » Sun. Jan. 18, 2009 10:08 pm

This stove has a thermostatic rear air inlet? How did I miss that? Of course CapeCoaler is right about adjusting that, too. You should be able to damp down the burn by reducing the air, so that your house doesn't get too warm. You'll burn less coal, too.

 
reckebecca
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Post by reckebecca » Sun. Jan. 18, 2009 10:13 pm

rberq wrote:This stove has a thermostatic rear air inlet? How did I miss that? Of course CapeCoaler is right about adjusting that, too. You should be able to damp down the burn by reducing the air, so that your house doesn't get too warm. You'll burn less coal, too.
I sent CapeCoaler a PM earlier in response to his post 'cause I didn't understand what he was intending for me to do - perhaps you can help me to understand since you're online and he isn't.

The thermostatic rear air inlet is what I have closed. The only front air that I believe I have is the air wash sliders on the front that folks told me to leave closed unless I was burning wood because they bring in air above the fire.

 
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Ashcat
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Post by Ashcat » Sun. Jan. 18, 2009 10:46 pm

Reckebecca--
I don't know the exact mechanism whereby your air intake closes, but I had a problem with my fire burning too hot even with my intake vent closed completely :shock: . Mine operates via the sliding of a thin metal plate to cover or expose the intake holes in the ashpan door. Turns out there is a nut that adjusts the tension on the sliding metal part. Even with the slider completely shutting off the holes, enough air was able to get through to cause the fire to burn too hot. By tightening that adjustment nut, this reduced the amount of airflow to permit me to manage the fire.

So, although I don't know how your intake mechanism works, see if there is any way to tighten up the gaps via some tensioning nut or other such device. FWIW.

 
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Cheetah
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Post by Cheetah » Sun. Jan. 18, 2009 11:08 pm

I did set the baro with a manometer - set it to maintain just below .05 measured with the manometer. I can get another thermometer and check the pipe temp. I did move the thermometer to the side of the stove and there was about a 50* temperature difference - it read 350* when on top it had read 300* just before I moved it.

When the intake air lever is set to "0" it is not completely closed, there is a sliver of light that I can see when looking through the ash door to the back of the stove (maybe open 1/2"?). Could it be that the cold temps outside are causing an increased draw on the chimney which compensates for the closed down intake? I've also gone through a lot more coal since closing down the air intake - I typically fill the hopper twice a day and I filled it this morning at around 7 and just had to fill it again at around 3 which is different. So, that would suggest that the fire is actually burning hotter and not simply that I was losing most of the heat up the chimney before shutting down the air intake. Before I closed the air intake down yesterday it had been at 1/2 open.
Decided to come out of lurking mode to offer my 2 cents. This is my first post to this forum and I am still new to burning coal myself. If I say something incorrect I am sure some of the experienced users will correct me and I wont be offended in the least.

The way these stoves control the burn rate is by restricting the air getting to the coal. If it can't get air it can't burn. The purpose of the baro is to provide a consistant draft. With a manual damper or no damper the draft will vary depending on outside temp, flue temp, wind, etc. That would cause the air flow through the coal to vary despite having a constant inlet setting. With the baro a given inlet setting should always provide the same air flow.

A manual damper works by restricting air flow from the stove. Burning coal with a limited air supply can produce carbon monoxide due to incomplete burning. With a baro the CO will go up the flue but with the manual damper it could leak out into the room if you close the damper too far.

Your stove is obviously getting enough air to keep a good fire going even with the temperture control set to zero. It is getting hotter in part because less heat was allowed to escape up the flue. It is using more fuel because the higher temperture of the coals promotes faster burning, provided it has enough air. To throttle it down a bit you need to further reduce how much air it takes in.

I was surprised to read that the air inlet was still open when it was adjusted to zero. Is there a stop that prevents closing it any further? Might there be some method of adjusting further? I think you should be able to get it for all practical purposes closed.

The other way to reduce the airflow is by reducing the draft. Try setting the baro back down to .03-.04 and see what you get. Then if you need more air flow open the inlet.

The bi-metal bar on the thermostat adjusts the inlet opening automaticly. If it starts to cool it opens further and closes if it gets warmer. If you have a fan aimed at the stove it can carry the heat away from the bi-metal bar causing it to behave as if the room were cooler, making it open the air inlet to make it hotter.

Bruce


 
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rewinder
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Post by rewinder » Sun. Jan. 18, 2009 11:26 pm

bekka, if your round thermostatic flapper is closed at the lowest setting of the handle thing, and the stove doesn't slow down it's output and darken, then you probably have some leakage thru your cleanout door gasketing. Try putting a piece of tin foil at various places between the stove and door gasket (after shutting the door with the foil "clamped" between) and see if it can easily be pulled out. maybe there is a way to tighten the door gasket if it slides out withno resistance.

from your response to cape coaler, is that the round thermostatic door will close shut, when you tun it down at a good high stove temp? I f it does shut close, then air is probably entering below the fire box thru the ash door I'm thinking.

BTW you should rename this thread--- Tooo Much Heat!!

 
reckebecca
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Post by reckebecca » Mon. Jan. 19, 2009 10:32 am

I think I got it (don't know if it's kosher the way I got it but, I stopped feeling like I was in a sauna!). I did end up opening up the air-wash vents and it cooled down the burn significantly. I got the stove back down to just under 300* and it only went through 1/3 of a hopper overnight (before shake-down) which is more typical of what it was doing before. This morning I shook down ash and closed the air-wash again to bring it up in temp again (it had dropped to just below 250*). The baro is also much quieter today. I've got temps at a much more reasonable 74* this morning.

 
braindead
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Post by braindead » Mon. Jan. 19, 2009 6:07 pm

I'd say its kosher. All the coal furnaces I remember as a kid had a firebox door damper to let some air in above the fire. It was a way to cut the draft through the fire while still maintaining good draft through the flue.

 
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Cheetah
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Post by Cheetah » Mon. Jan. 19, 2009 6:29 pm

Good thinking. Only down side is that the air you are letting in is carrying heat up the chimney. Turnning down the baro would reduce the flow through the coal without carrying off the heat. That way you could turn it down further and still get the heat you need while using even less coal. Might be worth experimenting with. At least you now have a way of getting the room temp where you want it :)

Bruce

 
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Post by rberq » Mon. Jan. 19, 2009 6:58 pm

Keep experimenting with the air wash vents and with the thermostat-controlled air intake. The more closed the better for the air wash vents, in my opinion. Once the fire is well-established you need little or no air entering above the coal bed.

You are still running at surprisingly low surface temperatures on the side of the stove. It's nothing for my stove to run 550 on the side, and when it's really cold out I give it lots of air and it goes to 750. I realize you don't need that much heat, but the point is, your stove should be able to do it. Then by turning back the thermostat it should idle back to 350 or whatever you need to be comfortable.

Keep experimenting, it will only get better from here on.

P.S. Lots of activity by the baro is usually a result of wind gusts.

 
CapeCoaler
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Post by CapeCoaler » Mon. Jan. 19, 2009 7:11 pm

I made an assumption that you had additional air input controls below the fire, in front like the Hitzers do.
In reading the posts since, you just have the air in back controlled by a bi-metal device attached to the flapper that controls the air intake.
With the over fire air shut and the back flapper shut do your fire temps still increase after 60 minutes?
If the air door in back stays shut the fire temps should drop due to air being cut off.
If the door is shut and fire temps are still rising you have an air leak into the bottom of the stove somewhere.
A smoke or smudge stick, it makes smoke you can see, will show where the air is entering as you slowly pass it around the bottom of the stove.
By having the over fire air open and bleeding off some draft you are slowing the burn in an inefficient way, it works in a pinch but is much like trying to slow a truck with the brakes while your other foot is still on the gas pedal!

 
reckebecca
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Post by reckebecca » Mon. Jan. 19, 2009 7:53 pm

I found the problem! :D I just took a flashlight to look and see how far open the flapper really was and what the problem might be. Well.......I swung the lever to the full open position and wouldn't you know.......a little piece of coal fell out! So, now, the flapper will fully close when it would not before! Yay, perhaps now I can close the windows without melting! :)

So, I have closed the air-wash and closed the flapper (should I leave it ajar or try it closes completely?) and we'll see what happens next. Ahhhh....the adventures of coal! :)

 
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Post by CapeCoaler » Mon. Jan. 19, 2009 7:59 pm

Keep the flapper just a crack open till you see where the stove settles down now that the flapper will actually close as designed.
If there is a chain connecting the Bi-Metal and the flapper make sure that the flapper is not shut with chain in a slack state.


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