It is standard practice for the majority of digital thermometers to display a "LO" sign when turning the device on. This means "LOW TEMPERATURE". This is because these types of thermometers are made to measure Body Temperature, so when outside the body, the temperature is usually LOWER. ... This means "LOW TEMPERATURE".

How do I fix the LO on my thermometer?

The 'Lo' or 'Hi' indications on the display mean that the temperature cannot be measured because the temperature is outside the temperature range. Press the on/off button to switch off the thermometer. Check if it is correctly positioned, press the on/off button again to switch it on, and re-start the measurement.

What does Lo mean on a thermostat?

The temperature sensed by the thermostat is lower than the 40 F (4 C) lower limit of the thermostats display range. The display will return to normal after the sensed temperature raises to within the 40 to 99 F (4 to 37 C) display range.