Flue temperatures first go...

[Swedishchef]

Hey guys

The wife isn't in the house so I gave it hell when I got home from work.
I lit my fire and got it going.

Without my bypass damper open, there's no way I can get my flue temperatures to 1000 degrees. It's just not happening. I think it could be a faulty reading though. I placed my thermometer quite high and after a 45 degree bend. My thermometer is about 24 vertical inches above my stove top, AFTER the first 45 degree bend. I even bought a new probe thermometer made by "imperial"

When I cork it with wood, I have some whicked secondaries on the go if I close my damper as tight as it goes. I am sure that just because my probe reads 400-500 degrees it's still a good temperature. And I can promise my stove top HAS to be "cured", the magnetic thermometer that I bought for the stove top indicates 950 degrees. It's H O T. It's not white or red, just really warm. BUt I presume those thermometers on stove tops (that were made for single wall stove pipes) keep aborbing heat, hence a high reading??

I will fire it up a few more times during the weekend to see if I can fix the smell for once and for all. Otherwise, I will be posting on this website to get input on a new Fn stove.

Andrew

 

[Highbeam]

It would be helpful to post a picture of your stove. You have a visible flexible liner as well as some vertical flue pipe with more than one bend in it. It's hard to imagine your setup.

If you can't get that probe meter over 500 then something is wrong. Perhaps that's your installation, the condar comes with directions that state that the probe should be 18" past the stove.

950 on the stove top is plenty hot. Did you get any new smoke from the stove paint burning off?

 

[Pagey]

If you didn't cure that baby at 950F, there's no curing it.

 

[Swedishchef]

Hey guys

I can't believe I did this..believe it or not, it's my first YOUTUBE video.
Here's my stove setup.

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

As you can see, the fire is going quite nicely. It is difficult to see my secondaries (camera isn't that great) but with my eye I could see them quite well.

Let me know what you think about my flu temps. Is it due to my 45 degree bend? Perhaps it's the probe. From what I can see of the probe, the probe itself warms up which in turn heats the metal band which then turns accordingly. Is this efficient? Are CONDAR probes built like this Imperial one?

Andrew

 

[Later]

Are we talking Fahrenheit or Celsius here?

 

[bokehman]

When you say probe what do you mean. Does that thermometer penetrate the stack or is it just on the outside of double wall?

 

[Battenkiller]

And I can promise my stove top HAS to be "cured", the magnetic thermometer that I bought for the stove top indicates 950 degrees. It's H O T. It's not white or red, just really warm. BUt I presume those thermometers on stove tops (that were made for single wall stove pipes) keep aborbing heat, hence a high reading??

950º Yikes, that's hotter than I've ever gotten the top of my stove by a hundred degrees. At a real 950ºF your stove top would definitely be glowing dark red, but you might need to be in the dark to see it clearly. I got a spot on my left door up to 1047ºF last week. You could see it glow in the light.

The flue thermos I have read the same as my IR does when they are placed on the top, so I think you either have a dud thermometer or you actually got the top that hot.

 

[BrotherBart]

If that thermo is reading right and you had pegged it like that the hot steel smell in that room would have been taking up all of your attention. Not the flue temp.

 

[Swedishchef]

The temp is in F.

What can I say: the thermometer is right there! I dunno what else I can do..what else can I do!?

The thermometer is a probe, it penetrates into the stack.

Next time I light a fire I am gonna turn the lights off and see if it is glowing. I don't think it is..but as I said, you see the temperature! Maybe I need to buy an IR gun. F! This is getting more and more complex. Any cheap (price) IR guns anywhere??

Andrew

 

[bokehman]

950º Yikes, that's hot...

950ºF (785K) is radiating 2kW per square foot. In a 50% efficient stove that's about 1kg of wood per hour per square foot. And that's not even taking convection or conduction into the equation. On the other hand if it is burning with the air wide open it's going to be pretty inefficient, maybe getting a 20% return on the wood if that.

 

[pen]

That's one damn hot stove top. I just can't explain that probe reading. Even at that height compared to 18 inches above the stove top, there is no way it would drop from reading at the high end of it's range (as I would HOPE with a 950 stove top) to only 400 something a little past the bend.

If you get a smell after this, the stove is possessed. There is no way in hell it's got anything left to outgas in my mind!

That is definately HOT

pen

 

[pen]

All I can tell you is all the testing I have done with Condar probes (and also done by Wes99 on here) shows that we have found them to read high. That is why I have it 28 inches above my stove top just so that I can get a reading that is "reasonable".

I loaded this stove at about 8:15-8:30 tonight (sorry I can't be more specific, I'm drinking)

These pic's were taken a little before 10 with the air adjusted so that it's about 1/10-1/12of the way open (prolly about 1/2 inch) or so. 2 air adjustments were made to get there, the last at about 8:45-9pm

(I wasn't going to make a fancy you-tube video in my current state, hope this will suffice) Your video came out great btw. I just wish I could explain your readings as they are certainly night and day from what I find.

 

[pen]

here is why I can't explain your low reading

When I had 2 thermometers installed, one 18 inches up from the stove, and the other 28 inches up, I only found about a 100 degree difference on average

pen

 

[Swedishchef]

I simply believe that my stove is posessed.
Simple
Poltergeist of 2010.
Hmm..if my stove keeps smelling, I am getting a new one. Simple.
It smelled quite a bit today during light up. That same old sweet/semi sweet smell coming from the stove top.

I don't know why I can't get higher temp readings. Maybe I need to try a CONDAR probe. Sigh. More $$$.

My video isn't fancy, I simply have a digital cam corder



Andrew

 

[pen]

I simply believe that my stove is posessed.
Simple
Poltergeist of 2010.
Hmm..if my stove keeps smelling, I am getting a new one. Simple.
It smelled quite a bit today during light up. That same old sweet/semi sweet smell coming from the stove top.

I don't know why I can't get higher temp readings. Maybe I need to try a CONDAR probe. Sigh. More $$$.

My video isn't fancy, I simply have a digital cam corder



Andrew

And that was one fine video.

I wish I could explain your reading, but I can't.

All I can say though, is if your stove still smells after having stove top temps like you had today, i'm agreeing w/ the ghost possibility.

pen

 

[Battenkiller]

Just now got an IR reading of 942ºF on that damn left door again. I had to shut the bypass damper to throw the stove into horizontal burn mode before the flue temp even hit 400º, then close down the inlet air so the temp wouldn't continue to rise. Single-wall pipe, temp taken about 18-20" above the collar... 385ºF. That's almost 600º lower than the stove face. I couldn't see it glow, even though the basement is kinda dark over there, but I shut out the light and you could see a diffuse glow coming from that spot. I used it as a target for another IR and got a reading of 914º by that time. I tried to take a photo, but no go.... not enough light at all.

This is a frustrating thing for me, because I don't want to leave the bypass open any longer once the face gets that hot, but the flue gases aren't yet hot enough to ignite in the secondary combustion chamber. If they get set off, I hear a very distinct rumble and the flue temps will rise about 50º before settling down to 400º or so. This time, no sound and the flue temps dropped back down to the low 200º range within about 15 minutes.

Anyway, my experience (with this stove at least) is that you can get extremely high stove temps without also getting very high flue temps.

 

[Backwoods Savage]

Has anyone considered the possibility of both thermometers being off? I ask this because we at one time had 3 thermometers on our stovetop and all reading differently. If my memory is correct, one read about 150 degrees higher than either of the others.

 

[Swedishchef]

Yes I have considered that the temperatures could be off, wrong. But I am not about to go purchased a thermocouple probe thermometer for my stove pipe. I MAY buy an IR gun.

Andrew

 

[pen]

This is the one I have and am happy with.

About 50 bux on amazon

http://www.amazon.com/IRT0421-Non-C...46-0752502?ie=UTF8&s=hi&qid=1266685094&sr=8-2

I liked the idea of buying it off of amazon since I could read all of the feedback. The only complaint I have with mine is it won't read temps on shiny surfaces for beans (like stainless steel) but I think that's pretty characteristic of all of these guns perhaps.

I'd say, find one in your price range with good reviews. Just make sure it's got a top temp of about 1000 at least

I use mine for tons of things other than the stove.

pen

 

[bokehman]

it won't read temps on shiny surfaces [...] like stainless steel

IR seems to work fine on my stainless flue, but then again, after 2 years use it's not shiny and is starting to look pretty stained.

 

[Battenkiller]

The only complaint I have with mine is it won't read temps on shiny surfaces for beans (like stainless steel) but I think that's pretty characteristic of all of these guns perhaps.

The emissivity of extremely polished metals is very low, so you need an IR gun that can be set for those surfaces. Most of the cheaper guns are calibrated for an emissivity of .95 because that works for most commonly found materials (including glass). I can set the emissivity on mine, but I wouldn't have a clue what to set it for. There are charts available, but like "bokehman" says, once things get stained up they no longer have those real low emissivities.

I use mine for so many things that I sometimes forget what I originally got it for and leave it upstairs instead of down by the stove.