7
Troubleshooting
Unable to power on
Press the On/Off/Set key for more than 0.3 seconds and try
again. Check whether the batteries have good contact and
the correct polarity.
Readings do not change
Check whether data hold function was activated (HOLD icon
at the left top).
Slow sensor response
Check whether the air flow channels on the back of the meter
are blocked.
Error messages
E01: CO
2
sensor damaged.
E02: The value is under range.
E03: The value is over range.
E04: Error code for dew point or wet bulb accompanying a
primary sensor failure code.
E07: Too low voltage to measure CO
2
.
Replace batteries.
E11: Retry humidity calibration.
E17: Retry CO
2
calibration.
E31: Temperature sensor damaged.
E34: Humidity sensor damaged.
