Thermapen ONE Trim Adjust Procedure

This procedure describes the method of trimming Thermapen ONE at a single temperature point (32°F/0°C) by using a properly made ice bath. The Thermapen should rarely need adjustment and should only be performed if absolutely necessary.

Materials Required:

• Philips screwdriver to open battery compartment
• Large kitchen cup (preferably 1 quart/1 liter size)
• Crushed ice (enough to fill cup)
• Water

Determining if Your Thermapen Requires Adjustment:

1. Make a proper ice bath:

• Fill a large cup with crushed ice.
• Add just enough water into the cup to fill in the gaps in ice so no ice floats off the bottom of the cup. Too much water will cause errors. Pour off water as necessary.
• Stir gently and wait approximately 1 minute.

2. Set the Thermapen display to read in tenths:

If the display is set to read temperature in whole degrees, change to tenths by following these steps:

• Using a Philips screwdriver, remove the battery compartment.
• Open the probe to turn on the Thermapen.
• Locate the Set and Menu buttons.
• Press the Menu button twice until 1 is displayed.
• Press the Set button to change the display from reading 1 to 0.1.
• To save the changes, press the Menu button until End is displayed.
• Replace the battery cover making sure not to overtighten.

3. Test the Thermapen display using the ice bath:

• Turn the Thermapen on by opening the rotating probe.
• Insert the tip of the metal probe into the ice bath about 2 inches (50mm) maximum.
• Stir gently so the tip does not rest on any ice. While stirring observe the displayed reading after about 15 seconds.
• Once the display is stable and no longer changes, write down the reading. You'll need this if the Thermapen requires adjustment.

4. Determine if an adjustment is necessary:

• If the reading from the ice bath test is within acceptable limits: 31.5°F and 32.5°F (−0.3°C and +0.3°C); then no adjustment is necessary.
• If the reading is outside of acceptable limits proceed to making the trim adjustment.

Making the Thermapen Trim Adjustment:

After determining that your Thermapen requires adjustment by following the above procedure, follow these steps to trim the Thermapen:

1. Turn the Thermapen off by folding the probe away and locking it into the probe retaining slot.
2. Calculate the trim adjustment value by subtracting the reading written down in Step 3 of ‘Determining if Your Thermapen Requires Adjustment' from 32.0°F (or 0.0°C).
   Example: Reading from my Thermapen = 32.9°F. Adjustment Value: 32.0°F - 32.9°F = −0.9°F
3. Using a Philips screwdriver, remove the battery compartment to access the Set and Menu buttons.
4. Open the probe to turn on the Thermapen.
5. Hold down the menu button for 5 seconds until ‘SET TRIM' is displayed. Press the Set button until the target trim adjustment value is displayed. Note the trim adjustment value range is from -3.6°F to +3.6°F (-2°C to +2°C).
6. Press the Menu button to save the trim setting, ‘END' is displayed for 1 second before returning to normal operation.
7. Retest in the ice bath to confirm that the new reading is within the acceptable limits: between 31.5°F and 32.5°F (-0.3°C and +0.3°C). If the reading is still outside of the acceptable limits, redo the trim adjustment by following steps 1 through 7.

For further technical assistance, contact Technical Support @ 801-756-7705 or techsupport@thermoworks.com.