Calibrating thermometers

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Lindsay Dive
Light Lager
Light Lager
Posts: 10
Joined: Wed Jan 03, 2001 7:03 pm
Location: Mona Vale, Ne, AU

Calibrating thermometers

Post by Lindsay Dive »

Can anyone tell me how to calibrate a thermometer?
JLaw
Posts: 6
Joined: Tue Mar 20, 2001 9:00 pm

What kind?

Post by JLaw »

If it has a needle and dial, not a digital or mercury thermometer, it should have a hex nut attached to the stem, on back of the face. Keep the thermometer in a known temperature solution, glass of ice water works best (32 degrees). Then put a wrench on the hex nut and hold it firmly, turn the face (dial) of the thermometer and turn it to the correct temperature. The face may not turn easily, that's okay, just keep turnin'! As for digital thermometers, some you can calibrate, some you can't. Depends on the manufaturer. And I know of no way to calibrate a mercury thermometer. Hope this helps some.

JLaw
Lindsay Dive
Light Lager
Light Lager
Posts: 10
Joined: Wed Jan 03, 2001 7:03 pm
Location: Mona Vale, Ne, AU

Alcohol & mercury

Post by Lindsay Dive »

The thermometres I have are the alcohol and mercury type. I placed both of them in boiling water (I live right near the beach/ sea level.)the mercury thermo was reading right on 100 deg c and the other which is an alcohol filled thermometer was reading 92 degrees c. I wanted to know if you can actually alter this type of thermometer. I also wanted to know how you can check to see if they are correct at say 67 degrees c which is probably the most important temp we need.
HugeElvis
Posts: 1
Joined: Sat Apr 22, 2000 7:01 pm

Thermometers

Post by HugeElvis »

You can't actually calibrate the liquid filled thermometers, but you can use a "factor" to +/- to the reading. Get the reading of boiling water and ice water. Hopefully the variance will be the same for both temperatures. The reading at 67 degrees should be close if the high and low readings are simliar. If they are way off, ask your local homebrew shop or buddies if they know anybody that works in a lab that has access to NIST rated thermometers. They can compare your thermometer reading to theirs and tell you the offset.
Jim
Lindsay Dive
Light Lager
Light Lager
Posts: 10
Joined: Wed Jan 03, 2001 7:03 pm
Location: Mona Vale, Ne, AU

Thermometers

Post by Lindsay Dive »

I do know a lady who works in a lab. I shall take you advice and talk to her.
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