Ever Lose Faith in Your ThermaPen?

My Mashes have gotten so much better since I bought a ThermaPen some 2-3 years ago. I love the thing. Although, last batch, my pen said I missed my Mash Temp by 3 degrees. 3 DEGREES!!! So, I will be brewing tomorrow, but I am going to change the batteries in the thermapen for this batch. If I am still being told that I am missing my mash temp, I'll be looking into my HLT Thermometer. But my question for you is, have you ever lost faith in your thermapen?

You know you're supposed to calibrate it from time to time, right?

aiptasia said:

You know you're supposed to calibrate it from time to time, right?

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No. Please explain. I did put it into Boiling water this morning, and it read 212. I placed it into a glass of Ice water, and it read 36 degrees. I think I did something wrong wit the ice water.

I'm confused. If you missed your mash temp, why is it your thermapen's fault?

Sounds like you need to adjust your strike temperature.

AZ_IPA said:

I'm confused. If you missed your mash temp, why is it your thermapen's fault?

Sounds like you need to adjust your strike temperature.

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Because it was the 19th batch of my house beer that I was brewing. Nothing has changed in this recipe in over 10 batches.

RLinNH said:

Because it was the 19th batch of my house beer that I was brewing. Nothing has changed in this recipe in over 10 batches.

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Grain temp and MLT ambient temp hasn't changed at all?

RLinNH said:

No. Please explain. I did put it into Boiling water this morning, and it read 212. I placed it into a glass of Ice water, and it read 36 degrees. I think I did something wrong wit the ice water.

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No, you did fine with the ice water. The pen just needs calibration because it looks like it's off by four degrees.

There are two adjustment screws on the back of the thermapen under the thermoworks label. One for hot, one for cold.

Click here for instructions.

AZ_IPA said:

Grain temp and MLT ambient temp hasn't changed at all?

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No, I am anal with this. I store Mash Tun and Grains in my house the night before every batch. I also Pre Heat my mash tun for 5 minutes, with the lid on, with 160 degree water. House is always, always at 73 degrees (first floor is).

The water/ice must be pure, as in distilled.

Use slush (crushed ice) with the water level slightly below the ice. When determining melting point remember that water is densest at 4C so the ice/water mixture must be continuously well stirred or the water at the bottom will be 4C and the rest of it somewhere between 0C and 4C (magnetic stirrer works best). A steady well-stirred temperature is 0.0C.

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-anonymous chemist

Are you sure you did the ice bath correctly? There’s a big difference between ‘ice-water’ and ice bath. http://thermoworks.com/learning/thermapen101_creating_an_icebath.html

Important points, ice above liquid, and stir.

Mash temps are hard to measure, because the mash is so chunky (read; non - heterogeneous). I depend on getting the strike temp right.

Wynne-R said:

-anonymous chemist

Are you sure you did the ice bath correctly? There’s a big difference between ‘ice-water’ and ice bath. http://thermoworks.com/learning/thermapen101_creating_an_icebath.html

Important points, ice above liquid, and stir.

Mash temps are hard to measure, because the mash is so chunky (read; non - heterogeneous). I depend on getting the strike temp right.

Click to expand...

Iidit wrong. I'll do it again. Thanks for all the great input so far!!!

The only thermometer I "trust" is a NIST traceable mercury thermometer. If you like the speed of your ThermaPen, calibrate it against a mercury thermometer before each brew.

Gizmos fail, when you need them most.

I hate thermometers. - HBT thread from 04/22/2012

I've had a Splash-Proof in Screamin' Yellow for a couple of years, use it for everything around the kitchen, barbecue, smoker and brewery. Fast, precise, and has never failed me yet.

If it tests off with fresh batteries it can be adjusted, but there is no manufacturer recommendation to perform periodic recalibration. Don't know where that came from...

Cheers!