PureAire Air Check O2 User manual

Air Check
O2Deficiency Monitor 0-25%
Instruction Manual
For model D Part number 99018
1140 Ensell Road
Lake Zurich, Illinois 60047
Phone: [phone]
Fax: [phone]
Toll-Free: 888-788-8050
pureairemonitoring.com
Rev 4.09 September 2022

Welcome to PureAire Monitoring Systems
I’d like to thank you for investing in our continuous life safety and process control toxic gas
monitoring systems.
PureAire offers an unbeatable combination of experience and innovation in solving the
safety and environmental needs of our customers. We can provide small systems of a few
points to a total multi-point turnkey computerized package.
PureAire’s proprietary sensor cell technology and state-of-the-art electronics are designed
to interface with the latest distributive or PLC based control systems. We believe that our
experience, innovative products, and commitment to service will satisfy your specific
monitoring needs now and in the future.
Our growth is a result of our total commitment to supporting our customers. We are
available 24 hours a day, 7 days a week to help you when you need us. Our 24-hour
Emergency phone number is 1-847-420-3814. We can provide field service, preventative
maintenance programs and training to your technicians in the operation of our equipment.
Our goal is to provide the best after sale service and support in the industry. That is just
one way PureAire takes that extra step to ensure your complete satisfaction.
Thank you again for investing in PureAire Monitoring Systems for your monitoring needs
and I’m proud to welcome you to our family of valued and satisfied customers.
Sincerely,
Albert A. Carrino
President

Please Read Before Installation
The following will damage the Air Check Oxygen monitor.
1. The Air Check O2monitor requires 24 VDC regulated power.
Please Do Not connect the monitor to any voltage that exceeds
24 Volts DC, or ANY AC Voltage.
2. Do not power the Air Check Oxygen monitor with the oxygen sensor
unplugged from the main PC board. Do Not Connect the O2sensor to
the PC board while the monitor is powered. This Will Damage the O2
sensor.
3. The oxygen sensor cell is matched to the electronics. Never exchange
the electronics with an oxygen sensor from a different monitor.
4. When calibrating or challenging the Air check O2Ex monitors,
a. Do not expose the monitor to flow rates that exceed ½ liter per
minute, (500 cc per minute) flow.
b. Expose the monitor to span gas blends that consist of
Oxygen and Nitrogen only. Do Not expose the monitor to
any combustible gas, i.e., Methane, Hydrogen, etc. Exposure
to combustible span gases can damage the oxygen zirconium
sensor cell.
5. Do not expose the Oxygen monitor to silicone, Freon, or corrosive
compounds. They can cause a loss of sensitivity and damage the
sensor.
6. Do not expose the monitor to high flow air or install it directly in front of
fans. The high air flow can cool the oxygen sensor and cause an
inaccurate reading.
7. When using the Air Check O2monitor, Do not expose the oxygen
sensor directly to a water stream. In areas requiring wash downs, cover
and protect the monitor and power supply. Contact PureAire for details on
a waterproof enclosure.
8. The Factory Password for entering the menus is 557

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Table of Contents
1: Introduction .....................................................................................................................2
1.1 Key Features ........................................................................2
1.2 Component identification ....................................................3
2: Specifications...................................................................................................................7
2.1 Performance Specifications .................................................7
2.2 Gas Detection System..........................................................7
2.3 Signal Outputs .....................................................................7
2.4 Electrical Requirements.......................................................7
2.5 Physical Characteristics .......................................................7
2.6 System Default Factory Settings .........................................8
3: Installation .......................................................................................................................9
3.1 Site Requirements................................................................9
3.2 Mounting..............................................................................9
3.3 Wiring ................................................................................10
3.4 Initial Startup .....................................................................10
4: Normal Operation..........................................................................................................11
4.1 Signal Outputs ...................................................................11
4.2 Instrument Faults ...............................................................12
4.3 Routine Maintenance Schedule .........................................12
4.4 Loss of Power Indicator.....................................................12
4.5 Alarm Reset .......................................................................12
5: Air Check O2Monitor Programming ............................................................................13
5.1 Joystick Operation .............................................................13
5.2 Program Flowchart ............................................................14
5.3 Entering the Password .......................................................18
5.4 Changing the User Password .............................................19
5.5 Entering the Menus............................................................22
5.5.1 Set 4-20mA Loop .....................................................22
5.5.2 Set Formats ...............................................................24
5.5.3 Set Alarm Threshold Polarity ...................................26
5.5.4 Set Latching ..............................................................28
5.5.5 Resetting a Latching Alarm ......................................31
5.5.6 Set Alarm Delay .......................................................31
5.5.7 Set Zero Suppression ................................................31
5.5.8 Set Alarm Thresholds ...............................................32
5.5.9 Set Alarm Hysteresis ................................................34
5.5.10 Set Sensor Adjust....................................................35
5.5.11 Main Operation Mode.............................................36
6: Maintenance & Cell Verification ..................................................................................37
6.1 Sensor Verification ............................................................37
6.2 Sensor Verification Procedure...........................................38
7: Appendix .......................................................................................................................41

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1: Introduction
The Air Check O2Deficiency Monitor is a compact gas monitoring system that is ideal for the
continuous monitoring of inert gas storage areas, confined spaces, and other locations where low
oxygen levels may pose a hazard to personnel. Unlike electrochemical sensor cells the Air Check O2
zirconium cell provides stable oxygen readings even in areas where temperature and humidity levels
are changing. The PureAire Air Check O2Deficiency Monitor is suitable for either indoor or outdoor
use*. Factory calibrated against a NIST traceable reference standard and UL, CUL and Ce approved.
The heart of the monitoring system is a long-lasting zirconium sensor, which responds to low oxygen
conditions within seconds and provides accurate measurements over a wide temperature and humidity
range. The zirconium O2sensor cell will operate continuously for 10 or more years and requires an
absolute minimum of maintenance. There are no zero or span calibration pots to adjust and when
compared to disposable type sensors, our long-life zirconium O2sensor can save up to hundreds of
dollars in annual maintenance.
Ideal for continuously monitoring oxygen levels in confined spaces or areas where inert gases are used,
the Air Check O2Deficiency Monitor does not drift or loose sensitivity when the weather or
temperature changes.
Each system consists of a long-life zirconium oxide sensor cell and three-wire transmitter. The Air
Check O2monitor may be used as a stand-alone gas detector, linked to optional PureAire single and
multipoint controllers, or connected to your own centralized control and surveillance system. This
manual covers the installation, operation, and maintenance of the Air Check O2deficiency monitor.
1.1 Key Features
The Air Check O2monitor incorporates several user-friendly features designed to simplify
installation, operation, and maintenance.
1.1.1 Long Life Zirconium Oxide O2Sensor
The system’s O2sensor cell has a life of well over 10 years of continuous operation. Unlike
concentration O2cells, PureAire’s exclusive zirconium oxide sensor cell does not need an oxygen
reference gas for proper operation. The Air Check O2monitor can detect low oxygen levels in
confined spaces and process tools without the need of a reference gas.
1.1.2 Smart Electronics
The Air Check O2monitor incorporates a special electronic circuit that continuously monitors sensor
operation. Cell degradation or complete failure will immediately be detected. This smart circuitry
alerts the user to sensor faults and other electrical problems that may interrupt surveillance through the
standard mA signal output signal or through the optional fault relay.
* For washdown areas use p/n 99118

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1.1.3 Calibration
The Air Check O2monitor incorporates a stable zirconium oxide sensor that rarely requires
calibration. Changing barometric pressure changes or changes in temperature and humidity do not
affect the zirconium oxide oxygen cell. The earth is a wonderful source of calibrated oxygen at 20.9%,
therefore under ambient conditions visual verification of the Air Check O2monitor to 20.9% oxygen
is easily performed. There are no zero or span pots to adjust. The O2monitor only requires periodic
testing with nitrogen to verify the cells response to low oxygen levels. See Section 6.2 for
the testing procedure to nitrogen.
1.2 Component Identification
1.2.1 Front View Exterior
1. Digital Display — 3-digit backlit LCD digital display for showing the
oxygen levels in percent.
2. Joystick — Used for selecting and adjusting the built-in menus. The Air
Check O2monitor is available with optional dual level user selectable
relays. The joystick is also used to select alarm levels, relay settings and
resetting any latching visual and audio alarms.
3. Cable Port — This is the opening in the transmitter housing for connecting
the 4-20 mA output and 24 VDC power cable.
4. Sensor Protector—The O2sensor is heated, and the sensor protector shields
the cell as well as provides airflow to the cell. It also has a ¼ “ diameter tube
fitting to permit connecting a nitrogen cylinder for testing the O2cell
response. NOTE: The sensor protector will feel HOT to the touch. This
is normal.
5. Oxygen Sensor — A zirconium oxide sensor, which detects and measures
the level of oxygen. When exposed to oxygen, the sensor outputs an
electrical signal proportional to the actual concentration of oxygen.
6. Mounting Feet — There are 4 feet used to mount the oxygen monitor to a
wall or other flat surface.
6
8
1
8
6
4 & 5
8
2
7
3

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7. Transmitter Cover — A removable cover that protects the interior of the
transmitter.
8. Transmitter Cover Fasteners — There are 4 captive screws secure the
transmitter cover in place.
9. Electronics Fasteners — These captive screws secure the electronics to the
enclosure
1.2.2 Front View Exterior
6
2
9
6
3
1
9
4 & 5

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1.2.5 Transmitter Interior
1. Main Power Terminal Block — This terminal block is where the main
power and 4-20mA analog output connection is made.
2. Sensor Cell Connector —This connector is where the Oxygen sensor
cell is connected. NOTE: Never connect the oxygen sensor to this
connector while the monitor is powered. This will damage the
oxygen sensor
3. PTC Resettable Fuse — The PCB is protected with a PTC Fuse that is
resettable and Never needs to be replaced. If it trips, you will need to
turn power off to the monitor. When power resumes the fuse will reset.
1.2.8 Enclosure Mounting Feet
1. Power and
analog output
Terminal
PTC Resettable
Fuse
Common
Common
mA output
+ 24 VDC
+ 24 VDC
Identification legend
Mounting Feet
Can be oriented
in any direction
Feet can also be
removed for
mounting the O2
monitor flush
with a wall or
other surface
2. Sensor cell
connector

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2: Specifications
NOTE: For our continual product improvement, all specifications are subject to change without notice.
2.1 Performance Specifications
Sensor Type: Long Life Zirconium Oxide Sensor Cell 0-25%
Response Time: Within 1 second of any change in O2.
Accuracy: ± 1% of full scale
Fault Indicators: Loss of VDC power (analog signal drops to 0 mA).
Sensor cell failure:
Operating Temp: -40° to 134°F (-40° to +55°C); consult PureAire for lower or higher operating
temperatures.
Humidity: 0 to 95% RH; consult PureAire for sensors which can operate in 100%
condensing RH environments.
UL / CUL listing: Measuring Equipment E363306
Ce EN 61000-3-2:2006 EMC, EN 61000-3-3:2008 EMC, EN61010-1-3-2013 LVD
2.2 Gas Detection System
Type: Long Life Zirconium Oxide Sensor Cell, Range 0-25%
Sensor Life: 8 to 10+ years under normal conditions.
Transmitter: Microprocessor electronics with built-in 3-digit backlit LCD display
Joystick operated menus
2.3 Signal Outputs
Local Display: Digital display calibrated for Oxygen. The range is stated on the model label
and can also be accessed via the joystick on the front panel. In the measurement
mode pushing the joystick down will scroll the gas and range on the display.
Push the joystick down again to stop the scrolling and display the gas again.
Standard Analog Output: DC 4-20 mA
2.4 Electrical Requirements
Power: 24VDC from external power source.
Consumption: Approximately 250mA
2.5 Physical Characteristics
Dimensions: 5.125 (W) x 3.15 (H) x 3.00 (D) inches; 130 x 80 x 76 mm (Max with feet)
Weight: 1.1 pounds (0.5 kg)
Enclosure Type: General purpose, Nema 2; not intended for explosive atmospheres.

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2.6 AirCheck O2System Default Factory settings
The Air Check O2Deficiency Monitor is shipped with factory defaults for the alarm relay settings.
The following are the factory defaults:
Menu Function
Factory Default
Menu Defined
Set 4-20mA loop
The mA output is set at
the factory using a
calibrated Fluke meter.
Use this function to adjust the
Oxygen monitors 4mA, (Zero) and
20mA, (Span) to your PLC or
distributive control system.
Sensor Adjustment
No factory default
For use when dynamically gas
calibrating the Oxygen monitor to
a known span gas.
See Section 6.2
Manage Passwords
Factory default is 557
For use when changing the
password from factory default to a
new password of your choice.
The following
Formats only used for
O2Monitors with Alarm Relays
Set Formats
LED and alarm relay
State **
Alarm 1 = Normal
Alarm 2 = Normal
Fault = Normal
Do you want the relays to
energize, (normal) or de-energize,
(fail safe) when the alarm
activates?
Set Alarm Threshold
Polarity
Alarm 1 = Inverted
Alarm 2 = Inverted
Audio = NA
Do you want to alarm at a level
higher, (normal) or lower,
(inverted) than the alarm
threshold?
Set Latching
Alarm 1 = Non-latching
Alarm 2 = Non-latching
Audio = NA
Do you want the alarm to
automatically reset? (non-latching)
or do you want to manually reset
the alarm? (latching)
Alarm Delay
Alarm = 5 seconds
How long do you want to wait
until the alarms activate?
Zero Suppression
000 = 0.00%
Refer to section 4.5.6
This function is Not Enabled on
the Oxygen monitor.
Set Alarm
Thresholds
Alarm 1 = 19.5 %
Alarm 2 = 18.0 %
Audio = NA
At what level do you want to
alarm?
Set Alarm Hysteresis
Alarm 1 = 0.0 %
Alarm 2 = 0.0 %
Audio = NA
For use when using the O
2
monitor
for control of valves and process.
See Section 5.5.9

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3: Installation
3.1 Site Requirements
The Air Check O2monitor enclosure should be mounted in an area free of vibration and electrical
noise or interference. If possible, avoid areas with high temperatures or condensing humidity.
The oxygen monitor covers an area of approximately 692 square feet when mounted on a wall and
should be placed no more than 21 feet from potential leak sources such as gas lines, gas cylinders, or
any areas where a gas leak might be expected to occur. To ensure safety, the maximum distance
between two monitors mounted to the same wall, should not exceed 30 feet.
WARNING: The Air Check  O2monitor is not designed for installation in
hazardous areas. Consult PureAire for information on enclosures for use in
hazardous environments.
3.2 Mounting
3.2.1 Transmitter Enclosure
The Air Check O2monitor is designed primarily for wall mounting and should be installed at a
height convenient for operation, maintenance, and viewing of the instrument display. The following is
a drawing of the mounting dimensions.
3.2.2 Air Check O2monitor
The transmitter and sensor should be installed in a location where gas leaks are likely to occur or
where released gases may accumulate. It should be mounted no closer than 12 inches above floor level.
Airflow within the monitored area, the characteristics of the gas (lighter or heavier than air), and the
position of workstations and personnel should all be considered in determining the most suitable
installation location.
5.50”
5.125”

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3.3 Wiring
The Air Check O2monitor requires a single, 3-wire shielded cable for analog output
and 24 VDC power input. A three-wire shielded cable; 3-conductor, 18 AWG stranded
General Cable E2203S.30.860, or equivalent is recommended for the connection. The
analog out and VDC power in connections are made on the terminal block inside the
transmitter housing.
These connections are made as follows:
* Caution: DO NOT connect to a powered current loop receiver. The Air Check
Oxygen monitor supplies the current loop power.
3.4 Initial Startup
Once installation of the gas detector has been completed, it is ready for startup. The following
procedures should be performed before putting the instrument into operation:
1. Check the integrity of all wiring.
2. Apply VDC power.
The instrument should now be powered up. Upon power up, the Air Check O2monitor LCD
displays the PureAire logo and then starts a 4-minute, (240 second) count down as the current to the
zirconium oxide O2sensor stabilizes. The monitor will output a 4-mA signal during the entire warm-
up period. After the countdown, the oxygen sensor will continue to reach its operating temperature for
approximately 30 minutes and the reading displayed will slowly increase to ambient. Do not make
any adjustments to the reading until after the monitor has been powered for at least an hour.
NOTE: The Air Check O2monitor’s reading may be adjusted to the ambient oxygen level.
See section 6.1 for instructions on adjusting.
Oxygen
239 WARM
-Common
-Common
mA* 4-20mA signal
output to PLC
+24VDC Power
+24VDC Power
Identification Legend
PureAire provides
the plug-in power
supply

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4: Normal Operation
The Air Check O2monitor is a single point monitor designed for the continuous detection and
measurement of ambient oxygen concentration levels.
4.1 Signal Outputs
The Air Check O2monitor outputs a continuous 4-20 mA analog signal proportional to the
measured concentration of oxygen. 4 mA represents 0% O2and 20 mA represents 25% O2which is the
full range. In the event of a system fault, a specific factory defined code will be displayed on the local
digital display. This code will indicate the exact nature of the system fault.
CAUTION: DO NOT connect to a powered current loop receiver. The Air Check
Oxygen monitor supplies the current loop power.
4.2 Instrument Faults
The Air Check O2monitor incorporates several self-checking features to
ensure reliable operation. If a fault condition is detected, the analog output
signal is altered: A few common error codes are displayed in the following
table:
Condition Analog Signal
Supply Voltage Out of
Range Fault code 16 Analog output drops to 2 mA
Transmitter cable cut Analog output drops to 0 mA
O2Cell complete failure
Fault Code 128
Analog output drops to 2 mA
Fault Relay activates
(Available with Relay Option Only)
O2 System Warm Up
Analog output drops to 2 mA
Fault Relay activates and turns off when system
is in the Oxygen operation mode
(Available with Relay Option Only)
O2Cell voltage fault
Fault Code 64
Analog output drops to 2 mA
Fault Relay activates
(Available with Relay Option Only)
EEPROM Fault 08 Analog output drops to 2mA
NOTE: If a Fault condition clears itself, the Fault message will continue to scroll until
manually cleared.
To clear the fault message, push the joystick down (- Minus)
NOTE:All system faults are displayed on the front panel. Each fault
has it’own specific code to identify the specific problem. Please
contact PureAire whenever a fault is displayed.

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4.3 Routine Maintenance Schedule
Continuous gas detection systems depended upon to measure and detect hazardous gas leaks in the
workplace requires periodic maintenance to ensure proper operation. The frequency with which this
routine maintenance is required depends on the environment. The following table is intended to serve
as a general guideline for routine maintenance. The conditions in your particular application, as well as
your organization’s maintenance policies, will ultimately determine the best routine maintenance
schedule for your equipment. Routine Visual Checks
Items to check Check for power and proper operation
Condition / status when
operating properly
Unit should be outputting a 17.4 mA signal when
the oxygen level is at 20.9%. The LCD digital
display should also indicate 20.9% 02when the
oxygen is at ambient levels.
4.3.2 Recommended Routine Maintenance Schedule
Routine Visual Checks Every 6 - 12 months
Sensor Verification with nitrogen Every 6 - 12 months**
** The ambient oxygen level is 20.9%; therefore, under ambient conditions visual verification of the
Air Check O2monitor to 20.9% oxygen is constantly being performed. The O2monitor only
requires periodic testing with nitrogen to verify the cells response to low oxygen levels. See Section
5.5.10 for how to make minor adjustments.
4.4 Loss of Power Indicator
In the event the Air Check O2monitor loses 24VDC power, the 4-20 mA analog output signal drops
to 0mA. The LCD display will also display a blank screen.
4.5 Alarm Reset (Only available on monitors with Relay and Alarm PCB)
It the Air Check O2monitor is supplied with the optional alarm relays, whenever the monitors alarms
are activated, the built-in alarm relays, panel mounted LED’s and optional audio horn will also
activate. When the relay settings are non-latching, the alarm relays, LEDs, and horn will automatically
reset. If the relay settings are latching, then a manual reset of the alarms are required. Resetting the
alarms can be performed through use of the joystick or using the remote reset function.
Joystick – You must enter the password to enter the reset function. After the password is entered and
accepted, push the joystick in; (enter) to reset the alarms.
Remote Reset – See section1.2.7. The alarm relay board has a two-pin connector for wiring to a
remote switch. When connected to a switch, this remote reset will bypass the joystick and a password
will not be needed to reset the alarms.
NOTE:The oxygen levels must recover above the alarm thresholds before the horn can be
reset from the remote reset switch or joystick.

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5: Air Check O2Monitor Programming
The Air Check O2Deficiency Monitor is supplied with user selectable settings to adjust the
alarm settings, 4 and 20mA output and minor sensor adjustments. The settings are arranged in
menus that are accessed by moving the joystick. To access the menus a factory set password is
used.
NOTE: The Air Check O2Deficiency Monitor will continuously monitor oxygen while
accessing the menus. The alarm, fault relays and mA output are all active and online while
making any changes to the menus.
5.1 Joystick Operation
The Air Check O2monitor uses a 4-position joystick with a center pushbutton for selecting
menus and changing values. The joystick is programmed to standard protocol as follows:
NOTE: The joystick has a built-in delay to prevent accidental tampering of the menus.
deliberate entries are required.
CAUTION: Only qualified personnel should perform programming, maintenance, and sensor
verification
+ Plus
-
Minus
Previous
Next
Plus – Pushing the joystick in this direction increases the value
Minus – Pushing the joystick in this direction decreases the value
Next – Pushing the joystick in this direction moves you to the next level of the menu hierarchy.
Previous – Pushing the joystick in this direction takes you out to the last level of menu hierarchy.
Enter – Pushing the joystick directly in the center enters the information into the microprocessor

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5.2 Program Flowchart
PassCode OK
PassCode OK Set 4-20mA
loop
Set 4mA
Zero
126
Set 20mA
Span
076
Oxygen
20.9%
Enter
Password 557
Force loop
Not available
Set Formats
Format
Relay 2
Format
Relay 1
Normal
Invert
Normal
Invert
Format Fault
Relay
Normal
Invert
NOTE: All
numerical values
shown are only
examples and are
not Factory
Defaults
NOTE: The
menus
highlighted in
light gray are
only used for
O2 monitors
with the Alarm
Relay Board
They are
displayed on
the O2monitor
and their
function is
disabled.

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Set Alarm
Threshold
Polarity
Set Alarm 1
Polarity
Normal
Invert
Set Alarm 2
Polarity
Normal
Invert
Alarm Delay
005
Set Audio
Alarm
Polarity
Normal
PassCode OK
Nonlatch
Set Latching
Relay 2
Set Latching Set Latching
Relay 1
Nonlatch
Latch
Nonlatch
Latch
Set Latching
Audio
Invert
Latch
NOTE: The
menus
highlighted in
light gray are
only used for
O2 monitors
with the Alarm
Relay Board
They are
displayed on
the O2monitor
and their
function is
disabled.

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Sensor
Adjustment
Set sensor
zero
Not Available **
Set sensor
span
055
Zero
Suppression
000 *
Set Relay 1
Alarm
19.5%
Set Relay 2
Alarm
18.0%
Set Audio
Alarm
19.5%
Set Alarm
Thresholds
PassCode OK
Set Alarm 1
Hysteresis
0.0%
Set Alarm 2
Hysteresis
0.0%
Set Audio
Alarm
Hysteresis
0.0%
Set Alarm
Hysteresis
NOTE: All
numerical
values shown
are only
examples
and are
Not Factory
Defaults
*
NOTE: Zero
suppression
function is not
available for
Oxygen
NOTE: The
menus
highlighted in
light gray are
only used for
O2 monitors
with the Alarm
Relay Board
They are
displayed on
the O2monitor
and their
function is
disabled.

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PassCode OK
Manage
Passwords
Enter New
User Password
Enter
minimum of 2
characters
Enable User
Password
Enabled
Disabled
Reset User
Password
Reset to
Factory
Default

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5.3 Entering the Password
The Air Check Oxygen monitor is supplied with a factory set password to prevent unauthorized access
to the menus. The Password is 557. The following explains how to enter the password.
1. Push the joystick once to the right. Enter Password will scroll on the first line of the digital
display. The second line will still display the current oxygen level.
2. Push the joystick again once more to the right to enter the input screen. The letter A will
appear and flash.
NOTE: The display has characters that start with A through Z and 0 through 9.
Pushing the joystick up or down will permit you to scroll through the
alphanumeric characters.
3. Push the joystick up or down to enter the first digit. The display is an alphanumeric display and
toggles from A through Z followed by 0 to 9. The character to be entered will flash.
4. Push the joystick again to the right to select the second entry. Push the joystick up or down to
select the second digit. The character being entered will flash and the first character entered
will remain lit.
5. Push the joystick again to the right to select the third entry. Push the joystick up or down to
select the third and final digit. The character being entered will flash and the first and second
characters entered will remain lit. You are now ready to enter the 3-digit password.
6. Push the joystick in the center to enter the password. If you entered it correctly the display will
scroll Password OK.
NOTE: If an incorrect password has been entered, the display will indicate Password
Failed. Push the joystick to the left to access the monitoring mode. From this mode you
can reenter the password again.
...PassCode OK……
20.9%
..Enter password…
20.9 %
A
20.9%
5
20.9%
55
20.9%
557
20.9%