Maintenance - Extech Instruments CO220 User Manual

When the alarm is ON, press the SET button to save the setting and
move to CO
The meter shows CO
High Alarm, press the SELECT button to increase the value (press and
hold the SELECT button to scroll faster). Press SET to save and press
ESC to return to the normal operating mode.
Now when the reading exceeds the programmed limit the meter will
beat once per second. The meter will sound the alarm until the
reading does not exceed the alarm limit, the user changes the alarm
limit value, the alarm is switched off as described above, or the meter
power is removed.
Automatic Baseline (ABC) Calibration
ABC (Automatic Baseline Calibration) establishes a baseline calibration
to eliminate the zero drift of the infrared sensor. The ABC function is
always ON when the meter is ON. ABC is designed to calibrate the
meter at the minimum CO
continuous monitoring (with power on). It assumes that the area being
tested receives fresh air with a CO
some period of time during the seven days. It is not suitable to use
desktop CO
2
a day.
NOTE: After the meter has been powered for one day, press the CO
button to determine if the environment is suitable for the automatic
baseline calibration.

Maintenance

Cleaning and storage
1. The meter should be cleaned with a damp cloth and mild
detergent when necessary. Do not use solvents or abrasives.
2. Store the meter in an area with moderate temperature and
humidity.
alarm setting.
2
1000 ppm as the default alarm. To change the
2
2
in closed areas with consistently high CO
reading detected during 7.5 days
level of approximately 400ppm at
2
11
levels 24 hours
2
CO220-en-US_V1.5 8/20
2