Extech Instruments CO220 User manual

USER MANUAL
CO2Monitor and Datalogger
Model CO220
Additional User Manual Translations available
at www.extech.com

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Introduction
Congratulations on your purchase of the Model CO220 Carbon Dioxide
Meter. This meter measures CO2 concentration, air temperature, and
relative humidity. The CO200 includes a 99 Memory Datalogger for
storing and retrieving readings with date and time stamping.
The audible alarms make this is an ideal instrument for indoor air
quality (IAQ) diagnostics. Carbon dioxide (CO2) is a gaseous
component of the earth’s atmosphere. The concentration of CO2in
natural ambient air is approximately 0.04% or 400ppm.
This meter is shipped fully tested and calibrated and, with proper use,
will provide years of reliable service. Please visit our website
(www.extech.com) to check for the latest version of this User Guide,
Product Updates, and Customer Support.
FEATURES
Extra Large LCD simultaneously displays CO2Level, Air
Temperature, & Relative Humidity
Displayed Calendar Clock.
Six (6) icons indicate indoor air quality levels (350 / 450 / 700 /
1000 / 1250 / 5000ppm)
Stable NDIR sensor for CO2detection
Automatic Baseline Calibration (ABC) function
Audible high CO2concentration alarm with selectable high alarm
threshold
Dew Point and Wet Bulb temperature measurements

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Descriptions
METER
1. CO2reading
2. Relative Humidity Reading
3. Air Temperature Reading
4. Time/Date Display
5. SET button
6. ESC –MEM button
7. SELECT –RECALL button
8. C/F - %RH button
9. CO2button
10. AC adaptor jack
NOTE: CO2, Temperature and RH sensors on rear of instrument

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DISPLAY SYMBOL DESCRIPTIONS
ppm CO2concentration unit of measure
350ppm to 450ppm
450ppm to 700ppm
700ppm to 1000ppm
1000ppm to 2500 ppm
2500ppm to 5000ppm
5000ppm and above
Air Temp Air Temperature
TWA Time Weighted Average (8 hrs)
STEL Short-Term Exposure Limit (15 minute weighted
average)
IPS% Liters per second per person
cfm/p Cubic feet per minute per person
WB Wet Bulb temperature
DP Dew Point temperature
MAX/MIN Maximum or Minimum reading

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PUSH-BUTTON DESCRIPTION
SET Enter setup mode
Save and confirm settings
ESC - MEM Exit setup and programming pages
End a calibration session
Memory Datalogger (99 points)
SELECT/RECALL Select/Recall and Clear Datalogger
Memory Readings
oC/oF - %RH Temperature/Relative Humidity
Modes/Temperature Unit changing
CO2CO2mode page stepping
Operation
POWERING THE INSTRUMENT
Power the unit by plugging the AC
adaptor into the meter and into an AC
source. The meter will switch ON with a
short beep.
Please use an appropriate power source:
100 to 240VAC (50-60Hz). The AC
adaptor’s output voltage is 7.5 to 9.0V
and its output current is 0.5A. Use of 3rd
party AC adaptor can damage the meter.
The LCD will display the current CO2
concentration , air temperature, relative
humidity, date, and time (date and time
toggle every 10 seconds). Six facial icons indicate the indoor air
quality level and appear on the top-tier display area (see figure at
right and the section titled Display Symbols earlier in this guide
for additional details).

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CO2MEASUREMENT CONSIDERATIONS
The meter starts measuring when powered ON and updates readings
every 6 seconds.
Response time is 10 seconds for CO2and 2 seconds for Relative
Humidity.
If the environmental conditions change (for example, a low to high
temperature swing) please allow 30 seconds for CO2readings and 30
minutes for Relative Humidity readings to stabilize.
NOTE: Do not hold the meter close to the mouth or any other source
of CO2.
CHANGE THE TEMPERATURE UNITS (oC/oF)
The change the displayed temperature units of measure:
1. Press and hold the SET button
2. While holding the SET button, press the oC/oF button
3. Repeat these steps to change the units again

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CO2DISPLAY PAGES
Press the CO2button to change the CO2display page on the top-tier
LCD area. The pages are shown below for CO2, Max-Min, TWA, STEL,
IPS% and cfm/p.
TIME WEIGHTED AVERAGE (TWA)
TWA is Time Weighted Average (8 hours); the meter updates the
reading every 60 seconds. If the meter has been powered on for less
than 8 hours, the TWA value will be the weighted average of readings
taken since the unit was powered ON.

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SHORT-TERM EXPOSURE LIMIT (STEL)
STEL is the Short-Term Exposure Limit (15 minutes weighted average);
the meter updates readings every 60 seconds. If the meter has been
powered on for less than 15 minutes, the STEL value shows the
weighted average of reading taken since the unit was powered ON.
LPS%
LPS% represents Liters per second per person.
CFM/P
CFM/P represents Cubic Feet per Minute per person.
VENT.R (CO2-based demand-controlled ventilation)
CO2-based demand-controlled ventilation refers to the practice of
using carbon dioxide concentrations as an indicator for a per-person
ventilation rate. In this context, CO2is monitored as a byproduct of
respiration rather than as an indoor contaminant. The rate at which
people produce CO2varies with diet and health, as well as with the
duration and intensity of physical activity. The more exertion an
activity entails, the more carbon dioxide is produced.
CHANGING THE 2ND TIER DISPLAY COMBINATION
Repeated presses of the C/F-RH% button step through the following
combinations of parameters:
Humidity + Air Temperature
Humidity + Web Bulb Temperature
Humidity + Dew Point Temperature

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MAX/MIN MEMORY
The meter automatically records Maximum and Minimum readings
when the meter is switched ON. In the normal mode, press the CO2
button to see the maximum and minimum levels of CO2. While
viewing the Max or Min reading, press and hold the SELECT/RECALL
button to reset the MAX or MIN memory. The “Clr”icon will appear
for 2 seconds and the display will begin tracking new MAX and MIN
readings.
DATALOGGER MEMORY 99 READINGS
The user can store up to 99 CO2
readings in memory for later recall.
Press the ESC-MEM button
momentarily to save the current CO2
reading with date/time stamp. The
meter will emit a short beep and the
memory location number will replace
the RH reading for 2 seconds before
returning to the RH reading.
Once the memory is full, the meter will
overwrite the first data point stored
and continue to overwrite existing
readings as new readings are stored.
To recall the data use the
SELECT/RECALL button. The middle tier
display will show the memory location number and the top tier
display will show the stored reading in ppm. The bottom tier
display shows the date/time stamp for the displayed reading.
Press the oC/oF-RH% button momentarily to return to the normal
operating mode.
Press and hold the SELECT/RECALL button to reset the 99 point memory
bank, the “Clr”icon will appear for 2 seconds before returning to the
normal display mode.

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Setup Mode
Press and hold the SET button for 2 seconds from the normal mode of
operation to access the SETUP mode.
Setting Year
When the two-digit year number appears, use the SELECT button to
increase the year value. Press SET to move to the next setting
Setting Month
When the two-digit month appears on the LCD press SELECT to
increase the month. Press SET to save and move to the next setting.
Setting Date
When the two-digit date appears on LCD press SELECT to increase the
date. Press SET button to save and move to the next setting.
Setting Hours
When the two-digit hour appears on the LCD press SELECT to increase
the hour. Press SET to move to the next setting.
Setting Minutes
When the two-digit minutes value appears on the LCD press SELECT to
increase the minutes. Press SET to move to the next setting.
High CO2Alarm
In the SETUP mode, after the date and time are set (as detailed above)
the A-on icon will be displayed in the upper display. Press the SELECT
button to switch the alarm ON or OFF. See diagram below.

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When the alarm is ON, press the SET button to save the setting and
move to CO2alarm setting.
The meter shows CO21000 ppm as the default alarm. To change the
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 CO2reading detected during 7.5 days
continuous monitoring (with power on). It assumes that the area being
tested receives fresh air with a CO2level of approximately 400ppm at
some period of time during the seven days. It is not suitable to use
desktop CO2in closed areas with consistently high CO2levels 24 hours
a day.
NOTE: After the meter has been powered for one day, press the CO2
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.

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Specifications
Function
Range
Resolution
Accuracy
CO2
0 to
9999ppm
1ppm
± (5%rdg +50ppm)
from 0 to 2000ppm
Temperature
14 to
140°F
(-10 to
60°C)
0.1°
1.0°F (±0.6°C)
Relative
Humidity
0.1 to
99.9%
0.1%
± 3% (10 to 90%)
± 5% (< 10% or >
90%)
@25°C
Display 3-tier Multi-function LCD
Sensor Type CO2: NDIR (non-dispersive infrared)
technology
Humidity: Capacitance sensor;
Temperature (air): Thermistor
Datalogging 99 points
Operating Conditions 32 to 122°F (0 to 50°C); 5 to 80% RH
Storage Conditions -4 to 122°F (-20 to 50°C); 5 to 90% RH
Power Supply 9VDC universal plug adapter
Dimensions 6.1 x 3.4 x 3.2” (155 x 87 x 81.5mm)
Weight 6.2 oz. (178g)

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Troubleshooting
Meter won’t power
ON
Check to see that the adaptor is properly
plugged in.
Slow response
Check that the air flow channels on the
rear of the meter have clearance.
Error Codes:
E-1
CO2sensor is
damaged
Return for repair
E-2
Humidity sensor is
damaged
Return for repair
E-3
Temperature sensor
is damaged
Return for repair
E-4
Operating
temperature is too
high
Put the meter in typical room
temperature for 30 minutes,
if problem persists, return
for repair
E-5
Operating
temperature is too
low
Put the meter in typical room
temperature for 30 minutes,
if problem persists, return
for repair
E-6
Hardware failed
Return for repair

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CO2Levels and Guidelines
IMPORTANT LIABILITY NOTE
The CO2guideline data provided here is meant for informational
purposes only and is not intended as a direct recommendation
from Extech Instruments or FLIR Systems. The user must take full
responsibility when determining how this information is to be
used.
Non-Enforced Reference levels
250 - 350 ppm –background (normal) outdoor air level
350- 1,000 ppm - typical level found in occupied spaces with good
air exchange.
1,000 –2,000 ppm - level associated with complaints of
drowsiness and poor air.
2,000 –5,000 ppm –level associated with headaches, sleepiness,
and stagnant, stale, stuffy air. Poor concentration, loss of
attention, increased heart rate and slight nausea may also be
present.
>5,000 ppm –Exposure may lead to serious oxygen deprivation
resulting in permanent brain damage, coma and even death.
Regulatory exposure limits
ASHRAE Standard 62-1989: 1000ppm: CO2concentration in
occupied building should not exceed 1000ppm.
OSHA: 5000ppm: Time weighted average over five 8-hour work
days should not exceed 5000ppm
Building bulletin 101 (Bb101): 1500ppm. UK standards for
schools say that CO2averaged over the entire day (i.e. 9am to
3.30 pm) should not exceed 1500ppm.
Germany, Japan, Australia, UK: 5000ppm, 8 hours weighted
average occupational exposure limit is 5000ppm.

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Two-year Warranty
FLIR Systems, Inc. warrants this Extech brand instrument
to be free of defects in parts and workmanship for two
years from date of shipment (a six-month limited warranty
applies to sensors and cables). To view the full warranty
text please visit:
http://www.extech.com/support/warranties.
Calibration and Repair Services
FLIR Systems, Inc. offers calibration and repair services for the Extech
brand products we sell. We offer NIST traceable calibration for most of
our products. Contact us for information on calibration and repair
availability, refer to the contact information below. Annual calibrations
should be performed to verify meter performance and accuracy. Product
specifications are subject to change without notice. Please visit our
website for the most up-to-date product information: www.extech.com.
Contact Customer Support
Customer Support Telephone List: https://support.flir.com/contact
Calibration, Repair, and Returns: [email protected]
Technical Support: https://support.flir.com
Copyright ©2013-2020 FLIR Systems, Inc.
All rights reserved including the right of reproduction in whole or in part in any form
www.extech.com