Here at ThermoWorks, we sometimes get calls from customers who swear that their old Thermapen seems faster than their new Splash-Proof Thermapen. And yet, we know the new Thermapens are actually faster than the old ones to get within 1 degree of the actual temperature—typically well under 3 seconds. This is due to an improved probe and the way the mini-thermocouples are manufactured.
Similarly, we’ve seen rumors on some forums and discussion boards about a mysterious “speed button” hidden inside the new Thermapen that can improve its performance.
Here’s the rub: The new Thermapens are set to show tenths of a degree whereas the old Thermapens showed only whole numbers. This can make it seem like it takes longer to come to a “stable temperature.” Watch the video below for a classic depiction of this. In the video, both Thermapen displays move from room temperature to within one degree Fahrenheit of the ice point (32°F) in 2 seconds (as you recall, the Thermapen spec calls for it to get within 1°F of the actual temperature within 3 seconds or less). But the display without the tenths settles on 32°F at 3 seconds while the display with the tenths takes an additional second to get to 32.0°F and even then dips a tenth or two momentarily before settling back on 32.0°F—which is not uncommon in an ice bath. In each frame of the video, the actual temperature being displayed is really the same, but the display without the tenths is rounding up or down and showing less information.
Of course, in a food or liquid that is being cooked the temperature is actually in flux and not stable like it is in a properly made ice bath. So the Thermapen displaying tenths of a degree would show even more movement and change in the tenths column as an actual reflection of the changing temperature. Thermapens do not lock in on a temperature like a radar gun or a bathroom scale, they accurately display the temperature at the tip of their probes in real time. Any changes in the display are actual changes in temperature. This is a very important concept. If you are measuring meat, for example, any change in the tenths column after 3 or 4 seconds is showing you the real temperature changing in the meat.
Those who are bothered by the extra digit can easily switch the display to showing whole numbers by changing the #2 mini switch in the battery compartment. Then it will behave like the old Thermapen, rounding off to the nearest degree. Some people prefer the rounding but it is no “speed button,” and many Thermapen owners prefer the additional information provided by the tenths digit.
Which way do you prefer to display the temperature on your Thermapen: with more information or with rounding to the nearest tenth? Be sure to comment below after watching the video a few times through (keep your eyes focused on the lower reading [without the tenths] while keeping aware of the upper reading to get the full effect—it goes by quickly!).