Hi, my name is Mike and I have been in the home improvement and repair field for 20 years. I will be very glad to help you today. To convert Fahrenheit (°F) to Celsius (°C) turn the unit off then back on. Within the first minute after turning the unit ON, press and hold the ALARM key and the POWER key simultaneously for five (5) seconds, then release. A “c“ will appear in the upper right of the temperature readings on the LCD.
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