Bacharach Comfort Chek 400 User manual

Instruction 1509-9000
Operation Manual
Rev. 4 - June 2013
Product Leadership
•
Training
•
Service
•
Reliability

Comfort Chek
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400 Operation Manual
ii 1509-9000 Rev 4

Comfort Chek
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400 Operation Manual
1509-9000 Rev 1 iii
TABLE OF CONTENTS
Important Note............................................................................................................iv
Warranty Policy ..........................................................................................................iv
Service Policy..............................................................................................................v
Notices ........................................................................................................................v
Disclaimer ..................................................................................................................vi
Revisions....................................................................................................................vi
1. OVERVIEW................................................................................................................ 1
1.1. Welcome ............................................................................................................ 1
1.2. Comfort Chek400 Shipping Checklist............................................................... 2
1.3. Key Features ...................................................................................................... 2
1.4. General CO2Guidelines...................................................................................... 2
2. SPECIFICATIONS ..................................................................................................... 3
3. COMPONENTS.......................................................................................................... 5
3.1. Power Supply ..................................................................................................... 5
3.2. LCD Display........................................................................................................ 5
3.3. Keypad ............................................................................................................... 6
4. OPERATION .............................................................................................................. 7
4.1. Power On/Off...................................................................................................... 7
4.2. Taking Measurements ........................................................................................ 7
4.3. Back Light........................................................................................................... 7
4.4. Data Hold ........................................................................................................... 8
4.5. MIN, MAX, TWA, and STEL................................................................................ 8
4.6. Audible Alarm ..................................................................................................... 9
4.7. Auto Power Off ................................................................................................... 9
4.8. Setup Mode ........................................................................................................ 9
4.9. P1.0 CO2Alarm Level......................................................................................... 9
4.10. P3.0 Temperature Units.................................................................................... 9
4.11. CO2Calibration................................................................................................10
4.12. RH Calibration Overview..................................................................................11
4.13. 33% Calibration ...............................................................................................11
4.14. 75% Calibration ...............................................................................................11
5. TROUBLESHOOTING ............................................................................................. 12
5.1. Cannot Power On ..............................................................................................12
5.2. Fixed (Unchanging) Readings............................................................................12
5.3. Slow Response..................................................................................................12
5.4. Error Codes and Descriptions ............................................................................12
5.5. Service Centers .................................................................................................12
6. CO2LEVELS AND GUIDELINES............................................................................. 13
6.1. Enforceable and/or Regulatory Levels ...............................................................13
6.2. Non-Enforced Guidelines and Reference Levels................................................13
7. NOTES..................................................................................................................... 13

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IMPORTANT NOTE
READ AND UNDERSTAND THIS MANUAL PRIOR TO USING THIS INSTRUMENT.
CAREFULLY READ THE WARRANTY POLICY, SERVICE POLICY, NOTICES,
DISCLAIMERS AND REVISIONS ON THE FOLLOWING PAGES.
THIS INSTRUMENT SHOULD BE INSPECTED AND CALIBRATED REGULARLY BY
A QUALIFIED AND TRAINED TECHNICIAN.
THIS INSTRUMENT HAS NOT BEEN DESIGNED TO BE INTRINSICALLY SAFE IN
HAZARDOUS OR EXPLOSION-RATED ENVIRONMENTS. FOR YOUR SAFETY,
DO NOT USE IT IN AREAS CLASSIFIED AS HAZARDOUS AREAS (E.G.,
EXPLOSION-RATED ENVIRONMENTS).
INSTRUMENT SERIAL NUMBER:
PURCHASE DATE:
PURCHASED FROM:
WARRANTY POLICY
BACHARACH, INC. WARRANTS THIS INSTRUMENT, EXCLUDING SENSORS, TO BE
FREE FROM DEFECTS IN MATERIALS AND WORKMANSHIP FOR A PERIOD OF TWO
YEARS FROM THE DATE OF PURCHASE BY THE ORIGINAL OWNER. THE SENSORS
HAVE A WARRANTY PERIOD OF ONE YEAR FROM THE DATE OF PURCHASE. IF
THE PRODUCT SHOULD BECOME DEFECTIVE WITHIN THIS WARRANTY PERIOD,
WE WILL REPAIR OR REPLACE IT AT OUR DISCRETION.
BATTERIES ARE NOT COVERED UNDER WARRANTY. WARRANTY DOES NOT
COVER DAMAGE FROM MISUSE.
THE WARRANTY STATUS MAY BE AFFECTED IF THE INSTRUMENT HAS NOT BEEN
USED AND MAINTAINED PER THE INSTRUCTIONS IN THIS MANUAL OR HAS BEEN
ABUSED, DAMAGED, OR MODIFIED IN ANY WAY. THIS INSTRUMENT IS ONLY TO BE
USED FOR PURPOSES STATED HEREIN. THE MANUFACTURER IS NOT LIABLE FOR
AUXILIARY INTERFACED EQUIPMENT OR CONSEQUENTIAL DAMAGE.
DUE TO ONGOING RESEARCH, DEVELOPMENT, AND PRODUCT TESTING, THE
MANUFACTURER RESERVES THE RIGHT TO CHANGE SPECIFICATIONS WITHOUT
NOTICE. THE INFORMATION CONTAINED HEREIN IS BASED ON DATA CONSIDERED
ACCURATE. HOWEVER, NO WARRANTY IS EXPRESSED OR IMPLIED REGARDING
THE ACCURACY OF THIS DATA.
ALL GOODS MUST BE SHIPPED TO THE MANUFACTURER BY PREPAID FREIGHT.
ALL RETURNED GOODS MUST BE PRE-AUTHORIZED BY OBTAINING A RETURN
MERCHANDISE AUTHORIZATION (RMA) NUMBER. CONTACT THE MANUFACTURER
FOR A NUMBER AND PROCEDURES REQUIRED FOR PRODUCT TRANSPORT.

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SERVICE POLICY
BACHARACH, INC. MAINTAINS AN INSTRUMENT SERVICE FACILITY AT THE
FACTORY. SOME BACHARACH DISTRIBUTORS/AGENTS MAY ALSO HAVE
REPAIR FACILITIES, HOWEVER, BACHARACH ASSUMES NO LIABILITY FOR
SERVICE PERFORMED BY ANYONE OTHER THAN BACHARACH PERSONNEL.
REPAIRS ARE WARRANTED FOR 90 DAYS AFTER DATE OF SHIPMENT
(SENSORS, PUMPS, FILTERS AND BATTERIES HAVE INDIVIDUAL
WARRANTIES). SHOULD YOUR INSTRUMENT REQUIRE NON-WARRANTY
REPAIR, YOU MAY CONTACT THE DISTRIBUTOR FROM WHOM IT WAS
PURCHASED OR YOU MAY CONTACT BACHARACH DIRECTLY.
IF BACHARACH IS TO DO THE REPAIR WORK, SEND THE INSTRUMENT,
PREPAID, TO BACHARACH, INC. AT THE FOLLOWING ADDRESS.
BACHARACH, INC.
621 HUNT VALLEY CIRCLE
NEW KENSINGTON, PA 15068
ATTENTION: SERVICE DEPARTMENT
ALWAYS INCLUDE YOUR RMA #, ADDRESS, TELEPHONE NUMBER, CONTACT
NAME, SHIPPING/BILLING INFORMATION AND A DESCRIPTION OF THE
DEFECT AS YOU PERCEIVE IT. YOU WILL BE CONTACTED WITH A COST
ESTIMATE FOR EXPECTED REPAIRS PRIOR TO THE PERFORMANCE OF ANY
SERVICE WORK. FOR LIABILITY REASONS, BACHARACH HAS A POLICY OF
PERFORMING ALL NEEDED REPAIRS TO RESTORE THE INSTRUMENT TO
FULL OPERATING CONDITION.
PRIOR TO SHIPPING EQUIPMENT TO BACHARACH, CONTACT OUR OFFICE
FOR AN RMA # (RETURNED MERCHANDISE AUTHORIZATION). ALL RETURNED
GOODS MUST BE ACCOMPANIED WITH AN RMA NUMBER.
PACK THE EQUIPMENT WELL (IN ITS ORIGINAL PACKING IF POSSIBLE), AS
BACHARACH CANNOT BE HELD RESPONSIBLE FOR ANY DAMAGE INCURRED
DURING SHIPPING TO OUR FACILITY.
NOTICES
COPYRIGHTS: THIS MANUAL IS SUBJECT TO COPYRIGHT PROTECTION; ALL
RIGHTS ARE RESERVED UNDER INTERNATIONAL AND DOMESTIC
COPYRIGHT LAWS. THIS MANUAL MAY NOT BE COPIED OR TRANSLATED, IN
WHOLE OR IN PART, IN ANY MANNER OR FORMAT, WITHOUT THE WRITTEN
PERMISSION OF BACHARACH, INC.
ALL SOFTWARE WHICH BACHARACH UTILIZES AND/OR DISTRIBUTES, HOLDS
A PROPRIETARY INTEREST AND IS ALSO SUBJECT TO COPYRIGHT
PROTECTION AND ALL RIGHTS ARE RESERVED. NO PARTY MAY USE OR
COPY SUCH SOFTWARE IN ANY MANNER OR FORMAT, EXCEPT TO THE
EXTENT THAT BACHARACH GRANTS THEM A LICENSE TO DO SO. IF THIS
SOFTWARE IS BEING LOADED ONTO MORE THAN ONE COMPUTER, EXTRA
SOFTWARE LICENSES MUST BE PURCHASED.

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DISCLAIMER
UNDER NO CIRCUMSTANCES WILL BACHARACH, INC. BE LIABLE FOR ANY
CLAIMS, LOSSES, OR DAMAGES RESULTING FROM OR ARISING OUT OF THE
REPAIR OR MODIFICATION OF THIS EQUIPMENT BY A PARTY OTHER THAN
BACHARACH SERVICE TECHNICIANS, OR BY OPERATION OR USE OF THE
EQUIPMENT OTHER THAN IN ACCORDANCE WITH THE PRINTED
INSTRUCTIONS CONTAINED WITHIN THIS MANUAL OR IF THE EQUIPMENT
HAS BEEN IMPROPERLY MAINTAINED OR SUBJECTED TO NEGLECT OR
ACCIDENT. ANY OF THE FORGOING WILL VOID THE WARRANTY.
REVISIONS
BACHARACH, INC. MAKES NO WARRANTY OR REPRESENTATION,
EXPRESSED OR IMPLIED INCLUDING ANY WARRANTY OF MERCHANTABILITY
OR FITNESS FOR PURPOSE, WITH RESPECT TO THIS MANUAL. ALL
INFORMATION CONTAINED IN THIS MANUAL IS BELIEVED TO BE TRUE AND
ACCURATE AT THE TIME OF PRINTING. HOWEVER, BACHARACH RESERVES
THE RIGHT TO MAKE CHANGES AT ANY TIME WITHOUT NOTICE. REVISED
COPIES OF THIS MANUAL CAN BE OBTAINED BY CONTACTING BACHARACH,
INC. OR DOWNLOADING IT FROM OUR WEB SITE WWW.MYBACHARACH.COM
SHOULD YOU DETECT ANY ERRORS OR OMISSIONS IN THIS MANUAL,
PLEASE CONTACT THE COMPANY AT THE FOLLOWING ADDRESS.
BACHARACH, INC.
621 HUNT VALLEY CIRCLE
NEW KENSINGTON, PA 15068-7074
USA
TOLL FREE: 1-800-736-4666
FAX: [phone]
E-MAIL: [e-mail]
WEBSITE: www.MyBacharach.com
IN NO EVENT WILL BACHARACH, INC., OR ITS OFFICERS OR EMPLOYEES BE
LIABLE FOR ANY DIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
DAMAGES RESULTING FROM ANY DEFECT IN ANY MANUAL, EVEN IF ADVISED
OF THE POSSIBILITY OF SUCH DAMAGES.

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1. OVERVIEW
1.1. Welcome
Thank you for purchasing the Comfort
Chek400
indoor environmental quality
monitor. The Comfort Chek400 is an easy-
to-use, portable device for monitoring indoor
air quality. It utilizes an infrared CO2sensor
plus temperature and relative humidity (RH)
sensors.
The Comfort Chek400 is a rugged, hand-
held, battery-
powered IAQ instrument for
measuring and displaying carbon dioxide
(CO2
), Temperature and RH indoors. It
operates from internal alkaline batteries or
wall adapter.
The Comfort Chek400 is equipped with
integral CO2, temperature and RH sensors to
aid in verifying readings providing an
indication of air quality.
NOTE: Calibration and repair are available at
our manufacturing facility and through some
of our authorized and trained distributors.
If after reading the manual you have any
questions, please contact our customer
service department for technical support.
Figure 1-1. Comfort Chek

400
Figure 1-2. Comfort Chek400 Kit

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1.2. Comfort Chek400 Shipping Checklist
This checklist ensures that you have received everything required to run your
Comfort Chek400. If you do not receive any of the items listed below, contact the
factory immediately.
•Comfort Chek400 instrument
•4 x “AA” alkaline batteries
•AC wall adapter (with North American plug)
•Operation manual
•Black plastic carrying/storage case
1.3. Key Features
Features of the Comfort Chek400 include the following.
•Displays CO2, temperature and RH simultaneously
•Stable NDIR sensor for CO2detection
•Statistics for STEL and TWA
•Backlit LCD display for dark areas
•Audible alarm for CO2readings
•Battery (operates up to 10 hours) or continuously with wall adapter power supply
•Easy user calibration for CO2
1.4. General CO2Guidelines
General CO2indoor air quality guidelines are summarized in the chart below. Aside
from the OSHA level of 5000 ppm for unsafe CO2levels, the other guidelines of
normal (300-400 ppm) and poorly ventilated (1000-1100 ppm) are generally accepted
standards for indoor air quality. Your guidelines may vary based on local practices
and personal preferences. Refer to Section 7 for additional information.
Figure 1-3. General CO2Guidelines

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2. SPECIFICATIONS
Categories/Subcategories Descriptions
Enclosure Dimensions H x W x D
6.63” x 2.75” x1.25” (17 cm x 7 cm x 3 cm)
Weight 7.1 ounces (200 grams) including batteries
Power
Battery Four alkaline batteries (4 x “AA”)
External
9 VDC from external AC adapter which is included in
kit (North American wall configuration only).
The end of the wall adapter that plugs into the
instrument is 1.3 mm diameter, center positive.
CAUTION: DO NOT use rechargeable batteries in
the Comfort Chek400 and DO NOT try to use the
wall adapter to charge them.
User
Interface
Display Three parameters, backlit, numerical LCD display
Audio
Alarms will sound at 1000 PPM, the ASHRAE limit.
The alarm level can be modified and the alarm sound
can be turned off through the instrument menu.
Warm-up 30 seconds
Environ-
mental
Temperature Operating: 0° to 50° C (32° to 122° F)
Storage: -20° to 700° C (-4° to 158° F)
Relative
Humidity Operating: 0 to 95% RH non-condensing
Standards Certifications CE
Sensors
Method Diffusion
Range 0 - 5000 ppm
Resolution 1 ppm
Accuracy ±30 ppm ±5% of reading (0 - 5000 ppm)
Pressure Dependence: +1.6% reading per kPa deviation from
normal pressure, 100 kPa
Temperature
Range: -10.0°
C to 60.0°
C (14°
F to 140°
F)
Resolution: 0.1°C (0.1°F)
Accuracy: ±0.6°C (±0.9°F)
Humidity
Range: 0.0% to 99.9%
Resolution: 0.1%
Accuracy: ±3% (10% to 90% range),
±5% (other ranges)

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Figure 2-1. Comfort Chek400 Dimensions

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3. COMPONENTS
3.1. Power Supply
The instrument is powered by either 4 “AA” alkaline batteries or a supplied DC wall
adapter (9V/1A output). Install batteries into the battery compartment on the rear of
the instrument and make sure they are in correct polarity and making good contact.
When the wall adapter is used it will cut off the power supply from the batteries. The
wall adapter cannot be used as a battery charger.
When battery voltage gets low, “Lob” will appear on the LCD and the audible alarm
sounds. The CO2infrared sensor cannot operate under low voltage, so the instrument
beeps to indicate failed CO2measurement. The user can press any button to stop the
beeps and at that time the sensor readings will not be displayed. To continue, replace
the alkaline batteries with fresh ones or connect the wall adapter.
Figure 3-1. Sample Low Battery Screen
3.2. LCD Display
Figure 3-2. LCD Components
NOTE: If the AC adapter is plugged
in while the instrument is powered
on, the Comfort CHEK400 will
lose power.
CO
2
concentration in PPM
Relative humidity in %
Air temperature, dew point,
or wet bulb temperature in
degrees C or F.

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LCD Symbol Description
TWA Time Weighted Average (8 hours)
STEL Short-Term Exposure Limit (15 minute weighted average)
HOLD Readings are frozen and remain unchanged
MIN/MAX MINimum/MAXimum readings
Low battery indicator
DP Dew Point temperature
AIR AIR temperature
WBT Wet Bulb Temperature
% Unit of measurement of relative humidity
°T (C/F) Celsius/Fahrenheit temperature unit of measure
3.3. Keypad
Keypad Button Description
Switches instrument on and off
Enters set up mode
Sets as non-sleep mode along with “HOLD”
Exits set up page/mode
Enters CO2calibration along with “MODE”
Enters RH calibration along with “DP/WBT”
Freezes the current readings
Cancels data hold function
Activates or cancels the backlight
Selects unit or increases value in set up
Selects AIR, DP, WBT temps display
Selects unit or decreases value in set up
Activates MIN, MAX, STEL, TWA functions
Saves and finishes settings

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4. OPERATION
4.1. Power On/Off
Press the SET button to switch instrument on. At power up, it emits a short beep and
performs a 30-second countdown while the instrument warms up. It then enters
normal operating mode displaying real time CO2, temperature, and RH readings. To
switch the instrument off, press the SET button.
Figure 4-1. Warm-up Countdown
Figure 4-2. Normal Operating Mode
NOTE: For the purpose of saving battery life, the unit will switch itself off after 20
minutes of operation. For continuous operation, switch the unit on using both SET and
HOLD buttons together.
4.2. Taking Measurements
The instrument starts taking measurements upon power up and updates information
on the LCD every second. When the environment to be monitored changes (example:
from high temperature to low temperature), it takes 30 seconds to update the CO2
reading and 30 minutes to update the RH reading.
NOTE: Do not hold the instrument close to your face because your exhalation will
affect the CO2, temperature and RH readings.
Press DP/WBT (down arrow) button to switch between the three different
temperature units of measure. The lower left portion of the LCD will cycle from air
temperature to dew point temperature to wet bulb temperature.
Figure 4-3. Dew Point Temperature
Figure 4-4. Wet Bulb Temperature
4.3. Back Light
Hold down MODE for more than 1 second to activate or cancel the back light function.

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4.4. Data Hold
Press the HOLD button to freeze the current readings. The HOLD icon is indicated at
the top left corner of the LCD. All current readings remain unchanged, except TWA
and STEL. Press the HOLD button again to cancel this function.
Figure 4-5. HOLD Mode
4.5. MIN, MAX, TWA, and STEL
While in normal operating mode, press MNX/AV to see the minimum, maximum, and
time weighted average readings. Each press of this button displays another readings
in sequence and finally returns to the normal operating mode.
In the MIN/MAX modes, the instrument indicates the minimum and maximum
readings for CO2on the upper half of the LCD, air/DP/WB temperatures in the lower
left corner of the LCD and RH in the lower right corner of the LCD (Figure a).
In STEL and TWA modes, the main part of the LCD indicates the time weighted
average for readings for CO2for the past 15 minutes (STEL) and past 8 hours (TWA).
The lower portions of the LCD are the current AIR, DP/WB temperatures readings and
current RH readings (Figure b).
NOTE: If the instrument is switched on for less than 15 minutes, the STEL value will
be the time weighted average of the readings taken since switch on. The same
calculations apply to the TWA readings indicated prior to 8 hours of operation.
NOTE: It takes at least 5 minutes of recorded readings to calculate the STEL and
TWA. The display indicates “- - - -” (Figure c) during the first 5 minutes of operation
from power on.
NOTE: While all the other readings are held unchanged, the STEL and TWA are
updated every 5 minutes.
(a) (b) (c)
Figure 4-6. Statistics Screens

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4.6. Audible Alarm
The instrument has an audible alarm to provide warnings to the user when CO2
concentrations exceed the limit (see P1.0 in setup for setting alarm threshold). It emits
beeps (about 80 dB) when measured CO2concentration exceeds the preset value
and stops when any key (except SET) is pressed or readings fall below the preset
alarm value. It beeps again when the value once again exceeds the preset limit.
Restart the instrument if the beeping cannot be stopped.
4.7. Auto Power Off
The instruments automatically switches off after 20 minutes of inactivity to save on
battery life. To override this function, power on the instrument by holding down the
SET and HOLD buttons for 2 seconds until “n” appears on the LCD.
NOTE: Auto sleep function is disabled during calibration mode.
4.8. Setup Mode
Hold down the “SET” button for more than 1 second while in normal operation mode
to enter the set up mode. To exit set up mode, press the CAL Esc button in P1.0 or
P3.0 and it returns to normal operating mode.
4.9. P1.0 CO2Alarm Level
When entering the set up mode, P1.0 and AL are indicated on the LCD. Press
MNX/AV button to go into P1.1 for setting the CO2alarm threshold. The current set
value will be blinking on the LCD. Press the MODE (up arrow) button or DP/WBT
(down arrow) button to change the set point in intervals of 100 ppm. Press the
MNX/AV button to save changes, or the CAL Esc button to exit without saving.
Figure 4-7. Entering Setup Mode Figure 4-8. Current Set Value (Blinking)
4.10. P3.0 Temperature Units
Press the MODE (up arrow) button or DP/WBT (down arrow) button in P1.0 to access
P3.0 for setting up the temperature scale. Press the MNX/AV button and it enters P3.1
mode with blinking °C or °F current settings on the lower left area of the LCD. To
switch between °C and °F, press the MODE (arrow up) button and DP/WBT (arrow
down) button. Then press the MNX/AV button to save the setting or CAL Esc button to
exit without saving and return to P3.0.

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Figure 4-9. P3.1 Temperature Scale Figure 4-10. Temperature Units
4.11. CO2Calibration
The instrument defaults to be calibrated manually in ambient air where CO2
concentration outdoors is around 400 ppm.
NOTE: Though not required, it is recommended that you calibrate the instrument
prior to each use. It is also recommended that the instrument be calibrated annually
by a trained technician or the factory using calibration gas.
NOTE: Do not calibrate the instrument in air with unknown CO2concentration
otherwise it will be calibrated as 400 ppm by default and the CO2readings displayed
will be inaccurate.
It is suggested to calibrate the instrument in fresh outdoor air that is well ventilated
and it is better in sunny weather. Do not calibrate the instrument in places crowed with
people or close to areas where CO2concentrations may be high such as ventilation
outputs, near exhaust, idling cars, garages, transportation depots, traffic, etc.
Set the instrument in the calibration site, switch it on and hold down the CAL Esc and
MODE (arrow up) buttons simultaneously to enter the CO2calibration mode. CAL and
400 ppm are blinking on the LCD while performing calibration.
Figure 4-11. CO2Calibration Mode
NOTE: Ensure either the wall adapter or fresh batteries are used for the calibration
procedure because the infrared CO2sensor draws a fairly high current. Low battery
voltage may result in an interruption or failed calibration.
Wait about 10 minutes until the blinking stops and the calibration is completed
automatically.The instrument returns to normal operation mode. To abort the
calibration, switch the instrument off at any time.

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4.12. RH Calibration Overview
The meter defaults to be calibrated at 33% RH and 75% salt solution. The ambient
condition is recommended to be at 25° C with stable humidity (it’s better to be close to
the calibration value). To abort the calibration, switch the instrument off at any time.
CAUTION: Do not calibrate the humidity without the default calibration salt solution
as it will cause permanent damage to the RH sensor.
4.13. 33% Calibration
Plug the sensor probe into a 33% salt solution bottle. Hold down the CAL Esc button
and DP/WBT button while in normal operating mode to enter the 33% calibrating
mode. CAL and calibration value (32.7% if at 25°C) are blinking on the LCD with
current temperature displayed on the lower left side.
The instrument is now calibrating and will finish in approximately 60 minutes when
CAL and humidity stop blinking.
Figure 4-12. 33% Cal Mode Figure 4-13. Cal Mode Finished
4.14. 75% Calibration
After 33% calibration, plug the sensor probe into a 75% salt solution bottle, then press
MNX/AV to enter 75% calibration.
CAL and calibrating value (75.2% if at 25°C) are blinking on the LCD with current
temperature indicated at the lower left corner. The instrument is now calibrating and
will finish in approximately 60 minutes when CAL and humidity stop blinking and the
instrument returns to normal operating mode.
NOTE: To calibrate 33% only, press CAL Esc and exit when 33% calibration is
complete. To calibrate 75% only, press MODE (arrow up) or DP/WBT (arrow down)
within 5 minutes of initializing 33% calibration.

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Figure 4-14. 75% Cal Mode
5. TROUBLESHOOTING
5.1. Cannot Power On
Press the SET button for more than 1 second and try again. In using batteries, ensure
that the batteries are making good contact and that they are installed with the correct
polarity. Otherwise, ensure that the wall adapter is connected and plugged in.
5.2. Fixed (Unchanging) Readings
Verify that the data hold function is not activated. In data hold mode, the HOLD icon
is displayed at top left corner of LCD.
5.3. Slow Response
Ensure that the air flow vents on the rear of the instrument are not blocked.
5.4. Error Codes and Descriptions
Error Code Description
E01 CO2sensor damage
E02 The value is under range
E03 The value is over range
E04 The original data error result in this error (DP, WB)
E07 Battery voltage too low to measure CO2. Replace batteries or use
wall adapter.
E11 Retry humidity calibration
E17 Retry CO2calibration
E31 Temperature sensor damaged
E34 Humidity sensor damaged
5.5. Service Centers
United States
Bacharach, Inc.
621 Hunt Valley Circle
New Kensington, PA 15068
USA
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Canada
Bacharach of Canada, Inc.
20 Amber St. Unit# 7
Markham, Ontario L3R SP4
Canada
Phone: [phone]
Fax: [phone]
Email: [e-mail]

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6. CO2LEVELS AND GUIDELINES
The following are excerpts from ANSI/ASHRAE addendum standard 62.1 – 2004.
Refer to section 1.4 for general CO2guidelines.
6.1. Enforceable and/or Regulatory Levels
•OSHA: 5000 ppm (The Occupational Safety and Health Administration)
•MAK: 5000 ppm or 10,000 ppm (1 hour) (German Institution)
6.2. Non-Enforced Guidelines and Reference Levels
•Canadian: 3500 ppm (long term)
•NIOSH: 5000 ppm or 30,000 ppm (15 minutes) (The US National Institutes of
Health)
•ACGIH: 5000 ppm or 30,000 ppm (15 minutes) (The American Conference of
Governmental Industrial Hygienists)
7. NOTES
•TWA (Time Weighted Average) value represents the average carbon dioxide
level exposure during 8 hours (working day).
•STEL (Short Term Exposure Limit) value shows the last 15 minutes’ CO2.
•ASHRAE: Standard 62-1989, Sec.6.1.3: Comfort (odor) criteria are likely to be
satisfied if the ventilation rate is set so that 1000 ppm of CO2is not exceeded.

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World Headquarters
621 Hunt Valley Circle, New Kensington, Pennsylvania 15068
Phone: [phone] •Toll Free: 1-800-736-4666 •Fax: [phone]
Website: www.MyBacharach.com • E-mail: [e-mail]