Flue probe Height

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Tar12

Minister of Fire
Dec 9, 2016
1,867
Indiana
Double wall pipe..18 in? or more?
 
Double wall pipe..18 in? or more?

I would just follow the directions. I think it's supposed to be 18". I fudged mine a tad lower so that didn't have to drill through the overlapped section of the double wall slip joint.
 
I would just follow the directions. I think it's supposed to be 18". I fudged mine a tad lower so that didn't have to drill through the overlapped section of the double wall slip joint.
Thats what I am running into...I won't have a choice but to go thru the overlapped section...be alright doing that I guess?
 
Put it so that it's easy to read, no closer than 18" or the thermometer will read a bit high. Ours is at 22".

From Condar:
Position so the thermometer can be read easily at a glance...
When properly installed, the FlueGard accurately reads flue-gas temperatures, with an error margin less than 5%. If placed closer than 18 inches from the top of your stove or furnace, the thermometer will read slightly higher.
 
Put it so that it's easy to read, no closer than 18" or the thermometer will read a bit high. Ours is at 22".

From Condar:
Position so the thermometer can be read easily at a glance...
When properly installed, the FlueGard accurately reads flue-gas temperatures, with an error margin less than 5%. If placed closer than 18 inches from the top of your stove or furnace, the thermometer will read slightly higher.
24 puts her about eye level...
 
I have previously drilled through all four layers for install of the probe meter. It works fine but be warned that the probe will lock the slip in place and require precision reassembly of the double pipe if you ever remove if for cleaning.
 
I did mine at 18" and yes i have to drilled thru the overlap but it is ok. As highbeam said follow the directions and it will be ok. when running the stove on low you will see real low temp in the 200df but it is ok.
 

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when running the stove on low you will see real low temp in the 200df but it is ok.

I do not believe that it is okay to run the stove with 200 degree flue temps. Think about what you're doing, condensing all of that water vapor into liquid within the flue. Nasty mess. There is a reason that the condar flue probe meter says anything under 400 is too cool. Oddly, the newest version of fluegard meter seems to think that 350 is the new low limit.
 
I do not believe that it is okay to run the stove with 200 degree flue temps. Think about what you're doing, condensing all of that water vapor into liquid within the flue. Nasty mess. There is a reason that the condar flue probe meter says anything under 400 is too cool. Oddly, the newest version of fluegard meter seems to think that 350 is the new low limit.
The cat is running midrange active and the flue probe is running 500...cruising right along...
 
The cat is running midrange active and the flue probe is running 500...cruising right along...

It's already running? You're going to need to post the install pics. We all love the pics.
 
that temp was like 14 hrs into the burn and the daytime temp climb and i dialed it a little lower. it stays like that for for the rest of the burn with sometime here and there touching about 325-350 df on the probe when the thermostat open a little and stove top into the low 400s df. i did checked the chimney last weekend, a quick check up and everything looks good, just some soot and most on the last 3-4 feet of my 19' stack. I will keep an eye on it for sure but i see no problem at this point.
 
It's already running? You're going to need to post the install pics. We all love the pics.
Its running on al load of well seasoned red oak...I couldn't play around with getting it up and running as the wife will be home soon...lol pics in a few.
 
Excuse the mess. This install is where the old BTU waster fireplace resided. I plan on installing stone veneer along the back corner. All pipe was Selkirk Ultimate One. SS outside stack and double wall inside with inner SS liner. I was torn between what stack height to go with 12 ft or 15 ft. and went with 12 ft after I saw the incredible draft on a cold stove....very happy so far! BTW....flue probe was set at 24 in.
 

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Congrats on the new stove.

Curious about the 600º flue temp. Was this with the bypass open or closed?
 
600º flue temp? Was this with the bypass open or closed?
closed...it is holding steady at 500 now.The cat is glowing a steady orange and it appears to be cruising right along...is that to high?
 
closed...it is holding steady at 500 now.The cat is glowing a steady orange and it appears to be cruising right along...is that to high?
Don't know, that's why I asked. May depend on the thermostat setting and a new stove will have a strongly active cat.
 
Don't know, that's why I asked. May depend on the thermostat setting and a new stove will have a strongly active cat.
I had the t-stat set at the 3 o'clock position initially(when pic was taken)and it is now set at 2;30 and is running at 500 and holding steady and this is a brand new stove being fired for the first time today
 
Congrats on the new stove.

Curious about the 600º flue temp. Was this with the bypass open or closed?

In this cold weather I've been running the stat at 50%, cat engaged, and the flue temps sit at 600 during the first half of the fuel load. Maybe 8 hours and slowly drops to 500. Only low burn rates get me to 400. Ultra low burn rates get me down to 200-250 with an active cat but that will lead to condensation in the flue so I try not to drop below 400.
 
closed...it is holding steady at 500 now.The cat is glowing a steady orange and it appears to be cruising right along...is that to high?

You're in great shape. The flue temps usually top out at about 800 during an extended high burn like an hour at max stat setting. 400 is low, and everything in between is normal. Pretty much just like your flue guard probe meter tells you.

Nice to see you already got the black glass starting. Those corners will stay dark and then the very corner will burn off occasionally which makes a cool dragon eyes picture if you can imagine it.
 
I'm surprised the flue temps are so high with a cat stove. On my tube stove i usually peak at about 600 flue temp then when I make my final air adjustment it sit around 450-500 until the wood is all coals.
 
I'm surprised the flue temps are so high with a cat stove. On my tube stove i usually peak at about 600 flue temp then when I make my final air adjustment it sit around 450-500 until the wood is all coals.

Sounds like the same thing with your temps just a touch higher. Most of the time these cat stoves are run on a very low setting corresponding to 400 or lower internal flue temps. During high output, the temperatures rise. All within the "normal" range of the flugard meter.

My non-cat internal flue temps just match the stove top temps and with a much higher flow rate until the coaling stage. If I'm holding 700 stove top temp then the surface of my single wall non-cat flue is at 350 which corresponds with a 700 degree internal temp.
 
In this cold weather I've been running the stat at 50%, cat engaged, and the flue temps sit at 600 during the first half of the fuel load. Maybe 8 hours and slowly drops to 500. Only low burn rates get me to 400. Ultra low burn rates get me down to 200-250 with an active cat but that will lead to condensation in the flue so I try not to drop below 400.
Good to know. These readings are similar to my flue temps of about 100º below stove top temp.
 
Good to know. These readings are similar to my flue temps of about 100º below stove top temp.


I love my BK but I know that it doesn't create heat with magic. We need to let these things burn more wood when we need to heat the house in colder weather. The efficiency of the BK is higher than a non-cat by something pretty small, say 10%, at a similar output rate. If I increase the burn rate for increased heat output and hold efficiency constant then by definition, flue temps must go up right?
 
I really can understand about the flue temp. but since i decide to buy a blaze king that was one of the things that i read about it. that the flue temp are low cause of the efficiency and the way this stove burn when they are on low settings. about the probe, gauges, or whatever we can call it, if you by one from a different manufacture, they all change the range for creosote and safe zone. i should have one that is 350 the creosote zone and 600 the overfiring. at that point i don't see where is the rules of thumb here.

I know i am new to wood burning compare to many here but i see my cat staying in the active zone regardless what is going on outside when we talk about outside temp without the need of touch the tstat. the only way that cat goes inactive is when 90-95% in there is ash. I run it all the time between 1/4 to 3/8 of an inch from the top end of the sticker ( maybe 1:00 o'clock or a little more?. not all situations and installs are the same like mention here millions of time. Here was where i learned that. in my set up works like that. For me to see 600 df stove top i don't need to run it at 3:00 or halve like some other owners here claim.

I am sure it is based on all those differences always mentioned here that we all know. my tstat stop right at 6:00 oclock. i don't know where it stop all the way counterclockwise cause i never turn the knob over the low end on the sticker, but for what i heard here it is calibrated right.

The manual just said that maybe in warmer weather you need to open more the draft to compensate draft, but nothing about the right flue temp. how many of stove owners has no flue probe?
 
here is a different scenario.
 

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