Last year was the first year I've had a wood stove and we bought a magnetic thermometer. Tried to keep the fire between the 300 and 500 degree range but had poor quality wood sometimes and had issues. Either way we have 9ft ceiling at the low wens where the stove is. Stove sits 3 feet high, then 4 feet of single wall pipe followed by 2 feet of double wall before it goes into a ceiling box and outside 4 more feet of double wall pipe. Great draft despite being shorter run. I have over described my setup for a probably simple answer for you all. What is going to be the better option for a flue thermometer? Magnetic or probe type? I used magnetic last year and after a year of burning the chimney only had about 1/8in of soft powdery buildup which easily brushed out. My kids decided to take down my magnetic thermometer and spin it around until the spring fell out. Shopping for a new one and wondered which is the best option.
Probe or magnetic thermometer
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Ashful
Minister of Fire
Probes are obviously needed for double wall, but if you're measuring on a single wall, the magnetic will suffice and is easier to mount.
This time, put a screw thru the center hole on the thermometer into the pipe, so the kids can't remove it. It also won't fall of, if you accidentally get the pipe past 700F (Curie temp).
Do note that outside pipe temps using a magnetic thermo should be roughly half of internal probe temps, but the ranges on the thermometers are usually marked appropriately for this.
This time, put a screw thru the center hole on the thermometer into the pipe, so the kids can't remove it. It also won't fall of, if you accidentally get the pipe past 700F (Curie temp).
Do note that outside pipe temps using a magnetic thermo should be roughly half of internal probe temps, but the ranges on the thermometers are usually marked appropriately for this.
Thanks! That's kind of what I've been reading during my searches but always welcome opinions on things like this.
As a test, I got an Imperial Flue-Gas Probe thermometer. It is much less expensive than the Condar and has an attractive minimalistic dial that I like. As it turns out, it's cheaper for a good reason. It's terrible for measuring flue temp. Straight from the package, it measured 200º low at 400º and 600º digital probe temp. It is also so glacially slow to react as to be useless. Like 10 minutes, to read 200º below the actual flue temp. Definitely avoid this one and get the Condar. Our ancient Condar went back into the probe hole. It also is slow, but not glacial and still relatively accurate.
![[Hearth.com] Probe or magnetic thermometer](https://www.hearth.com/talk/data/attachments/305/305169-bd54fe14e3c7d40af0cd0d06e75f69ee.jpg?hash=RGipGlOe5y "[Hearth.com] Probe or magnetic thermometer")
![[Hearth.com] Probe or magnetic thermometer](https://www.hearth.com/talk/data/attachments/305/305170-70007be87585db9b8bb2f900148f2238.jpg?hash=JyiNhQmsfm "[Hearth.com] Probe or magnetic thermometer")
If you want quick accurate temps the probe is the way to go. I've only been using my new stove for about 3 weeks now and I use a Auber probe. Its incredible how fast and responsive it is to the smallest adjustments I make with the stoves thermostat. Minor adjustments that one would never realize raised or lowered the stoves temp by 100 degrees or more. I have the Auber AT200, but the AT100 is a bit cheaper and does all thats needed to monitor the flu temp.
I see no reason it can't be used on single walled pipe. Its a must for double walled since a spring thermometer couldn't accurately measure the inner pipes temp. The probe is approx 4" long, which gets drilled into the pipe along with a screw to hold it in place. There is the option of getting a longer cable that runs between the probe and temp unit. If you want to get fancy, get the AB-210, it comes with a remote temp unit that works off the main temperature unit that's connected to probe via wire. It sends a constant wireless signal to the satellite unit where you could monitor anywhere in your home. Plus the main wired unit could be simply hide behind the stove and out of sight. The unit also has a built in alarm that alerts you if you go over your programmed high temperature setting. No directions are sent with the unit, but a two page manual is available on their website.
A couple weeks ago I got two of those. Both read low. According to my SST and IR, I’m around 575. According to the probes I’m 275. I have an Auber on the way. I hate I drilled a hole in the front of the pipe, just so I can drill one in the back. Maybe I can get it adjusted to read close enough to leave it in there for comparison and outages.
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I had the Condar years before I added the Auber. The digital probe is in the rear of the pipe, about 2" above. You will love it for the real-time reading of the flue gas temp. I leave the Condar in for power failures and to fill the hole. Thought the Imperial might be an update, but the readings are worthless. I was going to pass it on to a friend but will take the loss and toss it. It won't help them at all.
Sawset
Minister of Fire
I’ve been adjusting mine with the locking nut from time to time. Haven’t gotten it dialed in yet, but closer. When you tighten the locking nut, the dial turns sometimes so I have been having trouble getting it right. To be fair, I haven’t really put that much effort into it yet.
I tried that, but then it is wildly off at other ranges. Like 200º at room temp. Also, calibration does not change the incredible sluggishness. It's about 4 or 5x as slow as the Condar.
I'd skip the magnetic ones since i will second what others have said about them being very inaccurate. I use mine for a rough reference but fall back on an IR gun to tell me really what's going on. The magnetic therm will read 200° off sometimes.
It depends. There are some decent magnetic surface thermometers, but a lot of the common ones can be really off. FWIW, our stovetop thermometer is now 32 yrs. old and still reading within 10º of the IR thermometer reading.
I have a very old condar on my flue pipe that is pretty accurate when compared to the ir gun. I got a condar inferno for the stove top and its around 50 degrees off the ir gun.
So would the auber probe work for single wall pipe? Or would it being on the hot stove pipe mess with the reading?
What ever came of this inconclusive thread? I spent an hour reading through 5 pages with no definitive result or reply from Condar. The thread linked for results for future readers, that felt like a Western Union from the Doc moment, in page 4 is no longer supported.
https://www.hearth.com/talk/threads/is-this-flue-temp-probe-full-of-it.46304/
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https://www.hearth.com/talk/threads/is-this-flue-temp-probe-full-of-it.46304/
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Well, 11 yrs happened...
There was another thread wondering about using the Condar probe thermometer on single-wall. This is a different question than using the Auber probe. The Auber probe is just a probe with no bimetallic coil. The Condar's bimetallic coil most likely is calibrated for the cooler double-wall stove pipe temp vs the very hot single-wall stovepipe's surface temp.
In another thread, I think someone talked about trying to shield the probe thermometer from the heat of the single-wall pipe with a disk of metal, but honestly, I wasn't following that thread closely and don't remember if an outcome was posted.
Yes. I was digging back, but I was researching as well. I was hoping to see Condar say it was a bad batch, exchange the faulty thermometers and everyone was happy, or…Don’t trust a coil, likely with a combination of made in America, assembled in America or China, (with parts sourced from) (pick a county)…
The new FlueGard thermometer specifically states that "Only recommended for double-wall stovepipes." Installing it on single-wall would be an improper installation.
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