Kind of a newbie question

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bluedogz

Minister of Fire
Oct 9, 2011
1,245
NE Maryland
I've been heating about 2600 square feet with my old late-80's Sierra. Up to now, I have not paid much attention to flue temperature, firebox temp, or anything like that.

When I get the fire quite hot, hot enough to heat the room it's in above 90, the firebox starts roaring like a jet engine. I mean that I can hear air being forcibly sucked in the intakes and see a rolling flame of what I assume is combustion gases at the top of the firebox. I have decided to not open the door when this is going on- no need to add fuel, obviously.

The Mrs. is scared that this is "overfiring." Yes/no/maybe so?
 
One word...thermometer.
 
Why do you want to heat the room above 90?
 
Fair question, Dune... the stove is in a 70's-era rec room that is sort of off to one side of the main area of the first floor. If we get that room good and hot, a 6" desktop fan can push the heat to the remainder of the first floor and even a good part of the second.

And, yeah, I bought a thermometer. So, when it gets cold this question may answer itself.
 
bluedogz said:
Fair question, Dune... the stove is in a 70's-era rec room that is sort of off to one side of the main area of the first floor. If we get that room good and hot, a 6" desktop fan can push the heat to the remainder of the first floor and even a good part of the second.

And, yeah, I bought a thermometer. So, when it gets cold this question may answer itself.

Turn your fan arround so it points towards the stove.

Place it on the floor, in the cold denser air. Blow the cold air into the stove room. Much easier to move cold air. Doing this, you may not need to burn nearly as hot, as moving the cold air is far more effective.
 
Fascinating... and worth a try. That said, any thoughts on overfiring or not?
 
bluedogz said:
Fascinating... and worth a try. That said, any thoughts on overfiring or not?

Yeah, a jet engine in your living room is not good.

Have you checked or had your chimney checked?
 
You'll want to be careful to not overfire the stove or it may self destruct. It's tough, but it's no longer young. Never put a full charge of wood on a large hot coal bed. Burn down the coals first by opening up the air a bit.

I second the notion of taking a bigger desk or table fan and set the fan on the floor in the cool part of the house, pointing directly toward the stove room. This works surprisingly well and is often more effective than trying to blow heat out of the room.
 
That happened one night with this Sierra. In fact an hour after this pic was taken. The next day I located a cracked weld in the back of the firebox letting air into the back of the stove. Tried to seal it with furnace cement and the next night it happened again. The stuff fell out.

The next day an old friend of twenty-one years was thrown the hell out of my house. And throwing six hundred and fifty pounds out of your house, is a lotta work.
 

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Yeah, a jet engine in your living room is not good.

Why not?

Have you checked or had your chimney checked?

We've had a sweep out every year, though I'm unclear what they have actually done. Sometimes they ask to come inside for access to the stove, sometimes they don't. That was going to be a whole 'nother thread...
 
bluedogz said:
Yeah, a jet engine in your living room is not good.

Why not?

Have you checked or had your chimney checked?

We've had a sweep out every year, though I'm unclear what they have actually done. Sometimes they ask to come inside for access to the stove, sometimes they don't. That was going to be a whole 'nother thread...

Seriously?

My main fear would be starting a chimney fire.

I suppose your chimney is pretty clean after a roaring, but I would be uncomfortable.

Then, as the other two gentlemen discussed, the stove itself.

If you had an iron stove, it likely would have split in two by now.

Steel stoves are very durable, but even steel can have the life baked out of it.

I would actualy recomend two thermos, one for the stove and one for the stack, in your case.

In jet engine mode are you able to control the fire using the air inlet controlls?

If not, you should find out why, door gaskets, warped illfitting doors, and cracked weld seams come to mind.

I have an old steel stove. It was warped when I got it, but no cracks.

I use an infra red laser pointer digital pyrometer (about $20 these days), but I like to fiddle with things.

My stove is so airtight that I can essentially snuff the fire by closing the inlet air vents, and that is how I like and want it to be.
 
Indeed, seriously. Told you it was a newbie question!

I wasn't too concerned about a chimney fire, only because we've been diligent about having a sweep out.

>>In jet engine mode are you able to control the fire using the air inlet controlls?

I have not tried. Though I know that only three of the four door gaskets are sound- the edges of the active door are tight but the joint between the doors is not (gasket fell out entirely). That'll get fixed this weekend.

>>I would actualy recomend two thermos, one for the stove and one for the stack, in your case.

Easily obtained... what will they tell me?
 
I am guessing that there is a temp range that both the flue & firebox need to be in.
I am also guessing from the flavor of these posts that this behavior in my stove is not good.

So, upon obtaining such thermometers, what do these ranges need to look like? All the thermos on the rack have pre-marked ranges like "creosote," "good," and "danger."

My question actually came from the fact that there's a label inside the door that says "if the flue is glowing, you may be overfiring." Well, the flue isn't glowing, but the label made me think.

Also, maybe I'm being a little techno-geek- when this "jet-engine" occurs, what is actually happening in the stove? I would have thought burning of the secondary gases would mean very complete and efficient combustion, but you folks seem to think otherwise?
 
oldspark said:
For me, Jet engine mode=brown shorts mode. :cheese:
As in: "Honey I am going to light a fire, bring me the matches and my brown shorts."
 
bluedogz said:
I am guessing that there is a temp range that both the flue & firebox need to be in.
I am also guessing from the flavor of these posts that this behavior in my stove is not good.

So, upon obtaining such thermometers, what do these ranges need to look like? All the thermos on the rack have pre-marked ranges like "creosote," "good," and "danger."

My question actually came from the fact that there's a label inside the door that says "if the flue is glowing, you may be overfiring." Well, the flue isn't glowing, but the label made me think.

Also, maybe I'm being a little techno-geek- when this "jet-engine" occurs, what is actually happening in the stove? I would have thought burning of the secondary gases would mean very complete and efficient combustion, but you folks seem to think otherwise?

A good hot fire is good for complete combustion. It is always good to burn hot, with plenty ( meaning enough) of air for complete combustion.

The roaring noise is the sound of the massive amount of air being drawn in by the stove.

When I melt steel in my charcoil burning forge, I user a blower to add enough air to raise the temperature of my forge fire hot enough to melt steel.

When you let your stove run away in danger mode on your thermometer, the excess air rushing into the stove (which is the roaring sound you hear) is causing the same type of temperatures inside your stove. Much higher temps than the stove was designed for. Most stoves of any type will not last under prolonged conditions of over-firing.
 
Sounds like my main lesson for this season will be learning to control the fire better.
 
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