Changing the temperature scale varies by model. Please refer to your specific thermometer below for instructions:
ThermoScan® 7 IRT6520:
With the thermometer off, press and hold the power button.
After 3 seconds, the screen will rotate between C / SET / F / SET.
Release the power button when the desired temperature scale is displayed. It will beep to select the temperature scale and turn off.
ThermoScan® 5 IRT6500 & IRT6020:
Press and hold the start button.
The Thermometer will turn on and show the start screen, where you will see all of the symbols on the display.
Continue holding the button down, it will show C or F for one second and then change to say SET for one second.
The pattern will continue as you hold down the start button. F → SET → C → SET
To select the option you want, release the activation/start button when the setting you want appears on the screen.
ThermoScan® 3 IRT3030:
With the thermometer off, press and hold the Start button.
After about 3 seconds you should see an F or a C appear on the screen.
If you continue holding down the start button it will toggle between the two options.
Release the button when the setting you desire is showing on the screen.
BNT400 3-in-1 No Touch:
You’ll find a switch in the battery compartment that allows you to change the temperature scales.
BFH175 & NTF3000US The No Touch + Forehead thermometer:
Please remove the battery cover as if you were going to change the batteries.
Toggle the switch that is located between the batteries.
Select “C” for Celsius and “F” for Fahrenheit.