Instructions

TROUBLESHOOTING
Problem: The board is plugged into my Pi 400 but the power LED is not lit.
Solution: Check that the GPIO pins are lined up correctly with the socket. See
page 4.
Problem: The board is plugged into my Pi 400 but the power LED is flashing
rapidly.
Solution: This indicates a problem with the sensor. Sometimes, all it needs is for
the power to be reset by turning your Raspberry Pi off and on again. If you do this
and the flashing continues, you probably have a faulty board, so please contact
[e-mail]
Problem: I've just connected everything up, but the eCO2 readings seem wrong.
Solution: The type of sensor used in the MonkMakes Air Quality Sensor, will start
producing readings from the first time you connect it. However, the readings will
become more accurate with time. The datasheet for the sensor IC suggests the
readings will only start to become accurate after 20 minutes of running time.
Problem: I get error messages when I try to run the example programs.
Solution: Note: You may not have GUIZero installed. Please follow the instructions
here: https://lawsie.github.io/guizero/#raspberry-pi
Problem: I'm comparing the readings from this sensor with a true CO2 meter and
the readings are different.
Solution: That's to be expected. The Air Quality Sensor estimates the CO2
concentration (that's what the 'e' is for in eCO2) by measuring the level of volatile
organic compounds (VOCs). True CO2 sensors are much more expensive.
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