3 thermometers: which to trust - Home Brew Forums
Register Now For Free!

Home Brew Forums > Home Brewing Beer > Equipment/Sanitation > 3 thermometers: which to trust

Thread Tools
Old 06-07-2009, 03:26 PM   #1
nebben's Avatar
Nov 2008
Now legal in Utah
Posts: 1,145
Liked 12 Times on 12 Posts

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!

Reply With Quote
Old 06-07-2009, 03:41 PM   #2
Yuri_Rage's Avatar
Jul 2006
Posts: 14,291
Liked 813 Times on 514 Posts

I'd use the "lab grade" themometer for the mash. I'd rather accidentally mash a little low than high.
Homebrewed Blog..........YouTube Channel .......... Shirts, posters, etc

Reply With Quote
Old 06-07-2009, 03:54 PM   #3
Jun 2008
Posts: 402
Liked 4 Times on 3 Posts

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.

Reply With Quote
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Do you really trust using brass? ILOVEBEER General Beer Discussion 21 10-30-2009 04:40 PM
Should I trust my hydrometer? DNW Beginners Beer Brewing Forum 4 05-30-2009 03:27 PM
Do you trust your refractometer? BigNastyBrew Equipment/Sanitation 14 04-08-2009 10:15 PM
Do you trust Microsoft. Orfy Drunken Ramblings and Mindless Mumbling 7 08-03-2007 07:50 PM
can I trust my own opinion? not sure. jarrid General Techniques 6 06-26-2007 12:26 PM

Forum Jump