How to Recalibrate a Thermometer

Two common types of instant-read thermometers are digital (l.) and dial face (r.)

It's a good practice to recalibrate--or reset--your thermometer from time to time. Doing so will prevent inaccurate temperature readings. It's a great action to take in order to avoid improperly cooked foods. Proper calibrations can help you stay clear of food safety issues. Keeping your thermometer in top form can contribute to many advantages in your life, and it can even help you obtain a winning score from the health department if it is one that's used in a restaurant environment.

Things You'll Need

• Thermometer
• Deep pan
• Boiling water
• Large cup
• Crushed ice
• Water

Instructions

Boiling Point Method

1. Bring a deep pan of water to a rolling boil.

2. Remove the thermometer from its sheath. Slide the thermometer stem through the metal loop at the top of the sheath clip. This will protect your hand from the boiling water while you test and recalibrate your thermometer.

3. Insert the thermometer stem into the boiling water while holding the other end of the sheath. Keep the thermometer upright. The thermometer should register 212 degrees Fahrenheit--the boiling point of water at sea level. (The boiling point drops about one degree for every 500 feet of altitude, so compensate accordingly).

4. You can easily recalibrate the thermometer if you get an inaccurate reading while it is still in the water. Some digital models have a reset button that needs to be pushed to recalibrate the setting. Others require holding the on/off button for several seconds to activate the recalibration mode. If you're unsure, check the manufacturer's instructions.

Ice Water Method

1. Create an ice water bath in a large bowl. Use half water and half crushed ice to create the bath. Let ice water mixture sit for one minute.

2. Immerse the thermometer stem in the middle of the ice water bath. Make sure that the stem does not touch the side or bottom of the bowl. Let the thermometer sit for 3 minutes to allow the temperature on the display to stabilize.

3. Recalibrate the thermometer if necessary. Do this while it is still immersed in the ice water bath. Either push the reset button or hold the on/off button. This option will vary depending on the model. Simply check with your manufacturer's instructions if you have any doubts.

Tips & Warnings

• Always recalibrate your instant-read thermometer if it's been dropped or if it experiences an extreme temperature change.

• If using a digital instant-read thermometer, change the batteries regularly

Resources

• Safe Food Handling