Thermometer question

[Riggs1]

I got my new 10 gal Bayou Classic kettle this week and getting things ready for my first BIAB this weekend. What is the best way to calibrate the thermometer. It only goes down to 60 so I can't go with the ice/water. I already boiled some water and calibrated it to my digital thermometer. The directions say to calibrate it to the room temperature. Looking at it now after setting it to the digital, the room temp shows 87 degrees. So, which is the correct or best way to calibrate it?

 

[poislb]

You have to boil in distilled water to calibrate it correctly.

 

[Riggs1]

Even with the elevation issue, why would the thermometer not stay calibrated? I have emailed Bayou Classic several time and have not gotten a response from them. Kind of sorry now I bought their product.