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Old 06-07-2009, 03:26 PM   #1
nebben's Avatar
Nov 2008
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Statistically, should I should average the three and make adjustments from there? I just have to ask.

-Miljoco 0F-250F 5" dial thermometer with probe extending 1.25" free into cooler, with clearance around probe for water to enter sight glass
-Comark 1" dial thermometer
-"lab grade" glass alcohol filled thermomter

I just attempted to calibrate the two adjustable thermometers in a slushy glass of water, with just enough water to fill in between the crushed ice. All three thermometers read ~32F within a degree or less as far as I could tell. I filled my new cooler converted HLT with 10G to do a leak test on my new bargainfittings temperature+sight glass parts (awesome BTW!). My house's hot water is registering about 125F on the Miljoco mounted in its 1/2" NPT fitting. I tried the lab thermometer and immersed it about 10" down, and it registered ~132F. Little Comark 1" dial thermometer registered about 128F with its probe about 4" below the surface.

Assuming "you get what you pay for" holds true and the temperature with hot water rising above cooler water taken into account, should be between the Miljoco ~125F ($25) and the Comark ($9) ~128F?

It is raining today and I'm stuck inside with all my fermenters full...so I've got nothing else to ponder. Thanks for the inputs!

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Old 06-07-2009, 03:41 PM   #2
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Jul 2006
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I'd use the "lab grade" themometer for the mash. I'd rather accidentally mash a little low than high.
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Old 06-07-2009, 03:54 PM   #3
Jun 2008
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I agree with Yuri. Also, If the lab thermometer is off, it will be a linear offset. For example, my lab thermo measures 30 in a ice water slush and 210F in boiling water. I just add 2 to every measurement. I based my digitals off of the glass thermo. The dial thermos may be accurate in a certain range, and off more at other temps, as it seems you have experienced.

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