Which Thermometer would you trust..150 degrees difference.......

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GreenLiving57

Member
Aug 3, 2018
84
Southwestern USA
Hi,
Here are two thermometers - reading around 150 degrees apart......on top of my stove.

I was sold the one that says "use on stovepipe" by a local shop, who said it's accurate on stove tops - BUT, the other generic one I bought online, consistently reads a lot lower...........any opinions? Thanks!
Therm1.JPG
 
If you switch places do they give the same difference (i.e. is it location dependent)?
 
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I trust my eyes looking through the glass at the fire and at the top of the chimney. The thermometer on top is a curiosity.
 
If you switch places do they give the same difference (i.e. is it location dependent)?
Yes, I have moved them multiple times, it's always the same with the one reading higher. Not sure which one is accurate! For now I just average it out! ;)
 
Get a flue probe And use these as toys :)
 
Get a flue probe And use these as toys :)
Flue probes work pretty much the same as those magnetic ones and can easily be just as far off.
If someone actually wants to check one put it in your oven. Assuming your oven thermostat is known to be correct.



There is absolutely nothing wrong with magnetic thermometers for single wall pipe or stove tops.
 
Of course, I know that. My point is that a stove top thermometer is not that useful. A flue probe is more useful.
 
Of course, I know that. My point is that a stove top thermometer is not that useful. A flue probe is more useful.
Yes I agree stove top is pointless. I misunderstood what you were saying. But if the pipe is single wall a magnetic one is just as good.
 
I just look at the fire. It tells me all I need to know.
 
For me looking at the fire isn't accurate enough. There are times it's raging but the flue temp isn't where I want it yet. And other times it looks pretty lazy but the temp says it's time to shut back.

Although now all that matters is cat temp
 
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I have a Condar like yours that's probably 30 years old, on the stove top it checks the same as my IR gun. my money is on the Condar.
 
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Flue probes work pretty much the same as those magnetic ones and can easily be just as far off.
If someone actually wants to check one put it in your oven. Assuming your oven thermostat is known to be correct.



There is absolutely nothing wrong with magnetic thermometers for single wall pipe or stove tops.
I just had a new Condar FlueGard be off over 100 degrees (lower) than it's replacement. No questions asked though so good on them for the replacement.
 
Those type of thermometers are good for a rough estimate on temps, not actual. Just get a $30 IR gun if you want accurate stove top temps.
Those IR guns are not very accurate either. I've got three of them and the stt can vary as much as 100 deg. Like most others they just give you a rough idea.