Magnetic temp gauge and double wall pipe

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kwikrp

Feeling the Heat
Oct 21, 2008
299
SE Mass
Can you use a magnetic temp gauge on double wall stove pipe? Is it accurate ? What should you use then ?
 
kwikrp said:
Can you use a magnetic temp gauge on double wall stove pipe? Is it accurate ? What should you use then ?

No, No, This: http://www.condar.com/probe_meters_woodstoves.html

These are not the most accurate, but will give a reasonable indication of flue temp with double wall pipe.

If you want something that is really accurate you need to spring for a digital thermocouple probe.
 
kwikrp said:
Can you use a magnetic temp gauge on double wall stove pipe? Is it accurate ? What should you use then ?

This is worth searching the threads for, it's been discussed.

My vague recollection is the magnetic probes aren't particularly useful on double wall, and if you want a thermometer on double wall, a probe thermometer is the way to go. They are easily installed.

If you do, please know that the Condar flue probes give repeatable but not accurate readings--they read hundreds of degrees high at the high end. So don't let the new information freak you out because the reading is so high--the numbers on the gauge are rubbish. The Condars read even higher when mounted close to something hot on the outside, like a stove. So mount it as high up your pipe as possible--at least 30" above the stovetop, IIRC, and contrary to Condar's instructions to mount it lower.

HTH, and congrats again on your satisfaction with your new stove.

Remember, we want Photos. :)
 
Yes, you can absolutely use magnetic thermometers on double wall flue pipe!

Your temperature reading will be lower, but useful. I have one on a rear exit horizontal double wall pipe. From experience and with respect to the stove top temperatures, I got a good feel for what the stove pipe temp ought to be and use it as a gauge. With some trial and error, you can learn what temperature you are beginnng to get to hot in your double wall stove pipe and use that info to slow the stove down or turn it up.

Good luck,
Bill
 
[fail deleted] :)
 
WES999 said:
kwikrp said:
Can you use a magnetic temp gauge on double wall stove pipe? Is it accurate ? What should you use then ?

No, No, This: http://www.condar.com/probe_meters_woodstoves.html

These are not the most accurate, but will give a reasonable indication of flue temp with double wall pipe.

If you want something that is really accurate you need to spring for a digital thermocouple probe.

Where is a good place to purchase a thermocouple probe?
 
leeave96 said:
Yes, you can absolutely use magnetic thermometers on double wall flue pipe!

Your temperature reading will be lower, but useful. I have one on a rear exit horizontal double wall pipe. From experience and with respect to the stove top temperatures, I got a good feel for what the stove pipe temp ought to be and use it as a gauge. With some trial and error, you can learn what temperature you are beginnng to get to hot in your double wall stove pipe and use that info to slow the stove down or turn it up.

Good luck,
Bill

Single wall magnetic thermometers are not meant for use on double-wall pipe. When I take IR readings from our double-wall they vary a lot with just small location changes. Not sure why, maybe due to the swirl of hot flue gases? You'll get a change in temperature for sure, but is it always meaningful? Not sure. A probe thermometer is what is designed for this application and will give you consistent readings.
 
BeGreen said:
Single wall magnetic thermometers are not meant for use on double-wall pipe. When I take IR readings from our double-wall they vary a lot with just small location changes. Not sure why, maybe due to the swirl of hot flue gases? You'll get a change in temperature for sure, but is it always meaningful? Not sure. A probe thermometer is what is designed for this application and will give you consistent readings.

I stand re-corrected! :)

A source for bimetallic probes: http://www.northlineexpress.com/category/woodstove-thermometers.asp

Remember, the Condar probes are common, useful, and repeatable in their measurements, but tested to read 100s of degrees high at the top end. They are good for monitoring things and getting a feel for what's happening, but the dial's numbers and burn ranges are inaccurate.

EDIT: Oh you want thermocouple probes. I don't know--perhaps someone will chime in, or a thread search is in order. They are pricier

HTH, and good luck.
 
leeave96 said:
Yes, you can absolutely use magnetic thermometers on double wall flue pipe!

Your temperature reading will be lower, but useful. I have one on a rear exit horizontal double wall pipe. From experience and with respect to the stove top temperatures, I got a good feel for what the stove pipe temp ought to be and use it as a gauge. With some trial and error, you can learn what temperature you are beginning to get to hot in your double wall stove pipe and use that info to slow the stove down or turn it up.

Good luck,
Bill

I disagree, here is an example why, (this is copy/paste from another post.)

I really don’t think you will get any meaningful temp info from the surface of DW pipe.

I have a digital thermocouple probe inside my Simson DW stove pipe. Today when I started up the stove the internal temp was almost 1000 �F, and the outside surface temp (measured with a digital surface probe) was only about 150 �F .

As you can see the internal temp was more than 6.5 times the external temp. For a few dollars more get the Condar probe.
 
WES999 said:
I have a digital thermocouple probe inside my Simson DW stove pipe.

Hey Wes,

This might be useful to the OP, so not a complete threadjack--

Can you recommend a relatively inexpensive thermocouple to Todd and me? I know they're not cheap.

Thanks for the info. Burn long, and prosper.
 
Todd said:
WES999 said:
kwikrp said:
Can you use a magnetic temp gauge on double wall stove pipe? Is it accurate ? What should you use then ?

No, No, This: http://www.condar.com/probe_meters_woodstoves.html

These are not the most accurate, but will give a reasonable indication of flue temp with double wall pipe.

If you want something that is really accurate you need to spring for a digital thermocouple probe.

Where is a good place to purchase a thermocouple probe?

Condar makes a Digital Catalytic Monitor http://www.condar.com/digital_monitor_woodstoves.html

Looks OK but there are some things I don't like, a big drawback is it only goes down to 450*,
also it can only measure flue temp and you have to worry about replacing batteries. And perhaps most important is it does not have an alarm.


Apparently there is no commercially available source of temperature monitor/alarms, made specifically for wood stoves. So I designed and built my own. I think a monitor/alarm is a very useful accessory for a wood stove. I have a flue temp and a stove top monitor/alarm on my stove.

I don't think a week goes by without someone posting: "I left the door open and forgot", "My wife left the air open and walked away" " My stove was glowing red" etc. etc.

I have made several different versions of stove top and flue temperature monitor/alarms.


This is the latest version of temp monitor/alarm, it can measure stove top or flue temp depending which type of probe is installed. I am pretty happy with this one. http://www.youtube.com/watch?v=SMeH_VNncQs

Here is another version, this one is a temp monitor only, it has a nice easily readable, large display.
http://www.youtube.com/watch?v=MMBe3zONstw

Here is another one I made a while ago, http://www.youtube.com/watch?v=PXMpyJ6c150

You can PM me for more info.
 
kwikrp said:
Can you use a magnetic temp gauge on double wall stove pipe? Is it accurate ? What should you use then ?

You could use a magnetic thermometer on double wall stove pipe . . . but the readings will be wonky and not really give you any useful info.

Most folks go with a probe-style thermometer. I use a Condar thermometer for my double wall pipe . . . very easy to install . . . and while no stove thermometer out there is what I would call scientifically calibrated they give you a rough idea at what temp you're at so you know if you're burning too cool or too hot . . . my Condar magentic thermometer was actually pretty close to the temp I got from my IR gun . . . so I can only hope the probe style is relatively accurate as well . . . again . . . I wouldn't trust the figures if my life depended on it . . . but I trust the figures enough to give me a guide as to how hot I am burning.
 
You can absolutely use a magnetic thermometer on a double wall stove. Will it give you the inside flue gas temperature - no, but it will not give it to you on a single wall pipe either.

Further, on a Woodstock stove, you can use a magnetic thermometer on the stove top and that gives you about 1/2 of the temperature of the inside of the stove.

My point is - the temperatures that magnetic thermometers give is always relative to the source. If you learn your pipe's behavior relative to stove temperatures, stove pipe expansion, noise, etc. that are alarms things are getting to hot and note the stove pipe temperature, then the thermometer is giving you useful feedback in regards to your stove performance.

That being said, yes - you can absolutely use a magnetic surface thermometer on a double wall stove pipe with great results - I do it with my double wall pipe everyday.

Thanks!
Bill
 
I can see where it would work ok on double wall pipe if it was closer to the stove collar like Bill has, but the further away you go the cooler the temps. I also don't like the Condar probes, just don't seem accurate as a thermocouple.
 
WES999 said:
I have made several different versions of stove top and flue temperature monitor/alarms.

You can PM me for more info.

EDIT:
This is the latest version of temp monitor/alarm, it can measure stove top or flue temp depending which type of probe is installed. I am pretty happy with this one. http://www.youtube.com/watch?v=SMeH_VNncQs

Sweet!

For public consumption, can you just give an idea of the cost, skill and trouble involved in building one? I'm pretty handy with electronics.
 
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