Thermometer inaccuracies

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woodhog73

Minister of Fire
Jan 12, 2016
780
Somewhere cold !
sorry for sounding ignorant. But is there mercurary inside stove top thermometers ?

I don’t have one. Only place to put one on my insert is not at the hottest spot. So figured it wouldn’t tell me much and never used one. I keep an eye on my flames conditions avoid infernos keep very lazy flames with moderate secondary combustion visible. I once put an IR gun on the part that sticks out from the hearth and had 500 showing. Pretty safe number. But with all the over fire threads recently been thinking of getting a thermometer anyways. But I read how they are inaccurate.

If it’s got mercurary in it how can one thermometer reading be so different from another and be inaccurate ?
 
Stove thermometers have wound, bimetalic thermostatic coils. The cheapest and most common ones have a greater tendency to become inaccurate. If you stick with a decent one from Condar it should be ok. And with a IR gun you can verify this. FWIW out 38 yr old Sandhill is still accurate within 10º.
 
sorry for sounding ignorant. But is there mercurary inside stove top thermometers ?

I don’t have one. Only place to put one on my insert is not at the hottest spot. So figured it wouldn’t tell me much and never used one. I keep an eye on my flames conditions avoid infernos keep very lazy flames with moderate secondary combustion visible. I once put an IR gun on the part that sticks out from the hearth and had 500 showing. Pretty safe number. But with all the over fire threads recently been thinking of getting a thermometer anyways. But I read how they are inaccurate.

If it’s got mercurary in it how can one thermometer reading be so different from another and be inaccurate ?
No mercury. Just a coiled strip of metal. Expands or contacts based on temperature.