FLUIDX GasCheck G Series User manual

USER MANUAL
GASCHECK G SERIES

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© 2018 FLUIDX Equipment, Inc.
CONTACT US
PHONE/FAX
Phone: [phone]
Fax: [phone]
ADDRESS
FLUIDX Equipment, Inc.
139 W. 2260 S.
Salt Lake City, UT 84115
www.uidxinc.com
info@uidxinc.com
SMT-07-1015 rev B

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© 2018 FLUIDX Equipment, Inc.
CONTENTS
1. SCOPE .................................................................................... 1
2. SAFETY .................................................................................. 1
3. OVERVIEW ............................................................................ 2
4. BASIC OPERATION ............................................................ 12
5. MAINTENANCE .................................................................. 16

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1. SCOPE
This manual contains safety, operation, and maintenance information
for GasCheck G Series handheld snier leak detector. Our leak detectors
are designed to ensure safety when used properly. It is the responsibility
of the user to follow safety-related warnings, cautions, notes, and other
requirements described in this manual.
Should a question, comment or problem arise, the information below
is provided as a guide. When returning a unit for factory service or
calibration, contact Portable Leak Detectors for a return material
authorization number (RMA). The device should be boxed securely and
contain all contact information, including return shipping information.
If the device is being sent to the factory for service, a written statement
of the problem or symptoms should then be included. The RMA number
must be on the outside of the package or indicated on the shipping label.
2. SAFETY
Please read this manual in full before using the GasCheck G Series
instrument. Portable Leak Detectors takes no responsibility for damage,
injury or death resulting from misuse, misunderstanding or negligence
while using this gas detector. Please contact Portable Leak Detectors for
clarication on any aspect of this manual that is not understood or for
additional information.
2.1 QUALITY ASSURANCE
GasCheck G Series instruments are manufactured in compliance with
ISO9001:2000, which ensures that the equipment supplied to the customer
has been designed and assembled from traceable components, leaving
Portable Leak Detectors calibrated to traceable standards.
2.2 RESPONSIBILITY OF USE
Many gases are hazardous and can cause explosion, poisoning and
corrosion resulting in damage to property and life. It is the responsibility
of the person using this instrument to ensure it is being used in
accordance with this manual and that the instrument is functioning
correctly before use.
The GasCheck G Series handheld leak detectors can detect a large range
of gases but some gases are more dicult to detect. It is the responsibility
of the user to ensure the GasCheck instrument has the sensitivity to detect
the required gas before reaching potentially dangerous levels.

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2.3 DISPOSAL
Disposal of the GasCheck G Series its, components, and any used batteries
shall be in accordance with local and national safety and environmental
requirements.
2.4 CALIBRATION
Calibration service is recommended on a yearly basis. LACO Technologies
has an A2LA Accredited calibration lab which complies to ISO/IEC 17025-
2005 and ANSI/NCSL Z540-1-1994. Also complies with ISO-9001 quality
standard. Call LACO at 801-486-1004 for more information.
3. OVERVIEW
The GasCheck is a portable handheld gas detector instrument
predominantly used for detecting gas leaks and can detect almost all
gases to varying degrees. It is powered by standard AA size batteries and
will accept both Alkaline and Nickel Metal Hydride (rechargeable) types.
The GasCheck uses thermal conductivity as its means of detecting gas
which oers a robust sensor technology that requires practically no
maintenance beyond annual servicing.
All GasCheck G Series models have an easy to use graphical interface with an
intuitive keypad allowing simple function selection and adjustment. It can
be upgraded to add features without the need to be returned to the supplier
and without having to modify the internal rmware. It has an LCD display,
LED indicator and audible sounder than indicates the detected signal.
Table 1: GasCheck Specications
COMPONENT DESCRIPTION
TEMPERATURE 0 to 50° C (32 to 122° F)
STORAGE TEMPERATURE -25 to 70° C -(13 to 158° F)
INSTRUMENT CASE Polyurethane
DIMENSIONS L.390 x W.60 x H.50mm L (15.35” x W2.35” x 2.0”)
WEIGHT 0.5 kg (1.0 lb)
INGRESS RATINGS IP20
LENGTH OF LONG PROBE 300 mm *12”)
DETECTION TYPE Thermal conductivity
DETECTION TIME TO T90 1 sec (short probe) 9 sec (long probe)
CLEAR DOWN TIME 1 sec (short probe) 9 sec (long probe)
BATTERY TYPE Alkaline or NiMH AA (qty 4)
BATTERY LIFE AT 20°C (68°F) 40 hours (20 hours when using the backlight

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Table 2: GasCheck Replacement Parts
PART NUMBER DESCRIPTION
A-08045 Long probe
A-08043 Short probe
1/BH-01 Replacement battery holder
08024CPC8 Nozzle
A-08029 Box Wrench
CM515.0-4101FAG/1 Leak Standard with Rellable Helium Reservoir,
5x10-4 cc/sec
CM515.0-410SFA0/1 Open Style Leak Standard for use with helium
regulator and tank, 5x10^-4 cc/sec
3.1 APPLICATIONS
Common applications include:
• Quality assurance: Testing seal integrity after product manufacture
• Laboratory applications: Detection of leaks from mass spectrometers
and chromatograph equipment
• Industrial: Leaks from gas cylinders, pipe work and process equipment
• Medical: Testing of membrane materials and sealing of glove boxes
• Pneumatic: Valve seal testing.
3.2 UNITS OF MEASUREMENT
The GasCheck is calibrated against a 5 E-4/cc/s helium leak to allow
volumetric readings and also a 5000ppm helium to allow measurement of
concentrations.
Table 3: Selectable Units of Measurement
UNIT DESCRIPTION
cc/sec Cubic Centimeters per Second oers a reading that indicates
the volume of gas escaping into atmosphere from a single
point, i.e., leakage from a hold in a gas lled vessel or pipe.
ppm Parts Per Million is a concentration reading. The GasCheck G
will display the concentration being detected. However, it is
more dicult to gauge the quantity of leakage.
mg/m3 Milligrams per meter cubed is also a unit that measures
concentration. (See ppm above)
g/yr Grams per Year is an alternative measure leak rate.

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3.3 IMPORTANT NOTES
The GasCheck G Series range is NOT intrinsically safe, so it should not be
used in potentially explosive environment. Intrinsically safe GasCheck
instruments are available; please contact Portable Leak Detectors for more
information.
• Ambient air pressure, heat, and humidity can also aect readings.
• The GasCheck G range is NOT “gas specic”, i.e., it cannot dierentiate
between gases.
3.4 PACKING LIST
Please remove all packing material and then check the content of the
carry case against the list below before use. Should the instrument or any
accessory appear damaged or missing, contact the instrument supplier for
advise before use.
Table 4: Packing List
ITEM QTY DESCRIPTION CHECK
1 1 GasCheck G instrument w/short probe and nozzle tted
2 1 Long Probe
3 1 Box wrench to change probe
4 1 Spare battery clip
5 1 User manual
6 1 Calibration certicate
7 1 CD containing additional product information

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3.5 THERMAL CONDUCTIVITY
All gases conduct heat by varying amounts. If an object is heated and
the source of the heat is then removed, the object will eventually cool
down to match the ambient air temperature. This action occurs because
the ambient air surrounding the object carries the access heat into the
surrounding atmosphere. This principal is also the same for objects that
are cooler than the surrounding ambient air. Dissipation of heat into an air
atmosphere is known and is a predictable rate. However, if the ambient air
is replaced with an alternative gas like helium, the rate at which an object
cools down changes.
If the object mentioned above had its environment replaced with pure
helium it would cool down to the environment temperature about 6
times faster.

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The GasCheck G Series contains a heated thermistor bead that transmits
heat to a block of material that remains at a constant temperature. As air
passes through the detector chamber a constant amount of heat passes
from the bead to the block. Gases that are dierent to air will aect the
rate at which heat transmits from the bead to the block. These rates of
change are measured and displayed as leak rates.
The diagram below shows the basic functionality of the GasCheck Thermal
Conductivity sensor. A fan draws a small ow of gas through the probe and
into the sensing chamber. The thermistor bead heats up when electrical
power is applied. As air passes through the cell a constant level of heat is
transmitted to a Temperature Stable block through the air. This rate of heat
transmission is used to Zero the instrument.
When gases with dierent thermal qualities pass through the chamber,
the amount of heat being transmitted to the Temperature Stable block
changes. These changes are measured, calculated and displayed on the
GasCheck as leak rates or gas concentrations.
NOTE Some gases have similar thermal properties to that of
the air, therefore the GasCheck can only detect larger
concentrations of these gases.
NOTE Some gases have positive and other gases have negative
signals. To simplify the instruments function, the GasCheck
only display changes as positive readings.
NOTE The GasCheck G2 cannot dierentiate between gases.
Selecting a specic gas on the GasCheck G Series allows
the instrument to calculate concentrations of that gas only
if that gas is being detected.

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3.6 INSTRUMENT MAIN MENU
Once the GasCheck has run through its START UP routine it will display its
normal RUNNING SCREEN used when locating gas leaks. Before using the
instrument, the various settings should be adjusted to suit the application.
Pressing the ESC key while viewing this RUNNING SCREEN will access the
instrument’s MAIN MENU. Repeated pressing of the ESC returns the user
back to the RUNNING SCREEN.
Figure 1: Running Screen
NOTE The amount of functionality varies between models. See
Table 1: GasCheck Specicationsto nd which functions
relate to which model.

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3.7 RUNNING SCREEN
The GasCheck displays the RUNNING SCREEN whenever the instrument
is being used to detect leaking gas. The illustration below outlines the
various information and icons.
Table 5: Running Screen Display
FUNCTION DESCRIPTION
GAS SELECTION The GasCheck G2 and G3 display the gas being measured in
the top left of the RUNNING SCREEN. The GasCheck G2 will
display the gas selected at the factory only. The G3 model
has a range of gases that can be selected via an internal gas
table.
SENSITIVITY The GasCheck G has three sensitivity levels:
• X100 (times one hundred) — the most sensitive
• X10 (times ten) — mid range
• X1 (times one) — least sensitive
BATTERY STATUS When the battery symbol is lled in, the battery is full. When
the battery symbol is outlined, the battery is exhausted.
BACKLIGHT
INDICATOR
The backlight symbol shows the status of the backlight, even
in bright daylight.
GAS
MEASUREMENT
The GasCheck G2 and G2 measure the leak rate of gas
leakage in whichever units are selected.
SOUND
INDICATOR
The symbol shows if the sounder is on or o. If the semicircle
on the right of the symbol is present, then the sound is
switched on. If not, the sounder is switched o. The beep
that occurs with each key press can not be switched o.
BAR GRAPH The bar graph increases as gas is detected. This graph is not
scaled and should be used for indication only. The GasCheck
G1 has no measured units, so it relies on this bar graph to
indicate leakage. When gas is detected and the bar graph
has reached its maximum level, a dierent sensitivity level
can be selected to give a wider detection range.
PEAK HOLD
INDICATOR
When selected, peak hold displays the maximum
measurement on the display. Pressing the ENTER key resets
the reading but also logs the peak reading in memory.

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3.8 FUNCTIONS
The GasCheck instruments have a variation of functionality. Each of the
functions listed below has a number to the right of the heading. This
number indicates which function is included with each model.
Table 6: GasCheck Function Comparison
FUNCTION DESCRIPTION MODEL
CONTRAST Use this function to adjust the contrast of the GasCheck LCD (liquid crystal display).
Signicant variations in ambient temperature conditions can cause the display to
appear too dark or too light.
When this function is selected, a number will appear to the right of the Contrast
symbol as a percentage. Use the UP and DOWN keys to adjust the display the contrast
to the desired level. When satised with the contrast level, press the ESC key to exit to
the MAIN MENU.
G1, G2, G3
BACKLIGHT The user can select either BACKLIGHT ON or BACKLIGHT OFF. In daylight, the user may
not be able to determine if the backlight is ON or OFF. A symbol on the main RUNNING
SCREEN shows the status.
When the backlight is ON, it signicantly reduces battery life.
Backlight O=40 hours of use
Backlight On=20 hours of use
G1, G2, G3
SOUND The GasCheck has an audible sounder that increases frequency as detected gas levels
increase. This sounder can be switched ON and OFF. Use the UP or DOWN key to move
the “tick” to the desired position and then press the ESC key to return to the MAIN
MENU.
An audible beep can also be heard whenever the key pad is
pressed. This beep cannot be switched o.
G1, G2, G3
PEAK HOLD When selected, this function holds the highest detected
reading on the display until the ENTER key is pressed.
Select Peak ON or OFF using the UP or DOWN key and then
press the ESC key to exit to the MAIN MENU.
When using the GasCheck G, press the ENTER key to clear the held reading. The
reading held on screen will be logged when the ENTER key is pressed.
WARNING: ZEROing the instrument in a contaminated environment will result in false
readings.
G2, G3
CALIBRATION There are two Calibration settings that can be selected:
FACTORY and CUSTOM. Factory calibration is carried out shortly
after manufacture and cannot be adjusted. However, custom
calibration oers the ability to calibrate the instrument between
annual Factory calibrations. The GasCheck G ZEROs its reading
at switch ON. Therefore, the Custom calibration routine has only
one stage. For more information, see 5.1 CALIBRATION..
BATTERY
SELECTION
The GasCheck will operate using AA size batteries in either
Alkaline (non rechargeable) or Nickel Metal Hydride
(rechargeable).
Select the battery type using the UP or DOWN key and then
ress the ESC key to exit to the MAIN MENU.
Failing to select the correct battery type will not damage the instrument or aect its
ability to detect gas. However, it will cause the battery indicator to read incorrectly.

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FUNCTION DESCRIPTION MODEL
VIEW DATA The GasCheck instrument has the ability to data log 10 readings within its internal
memory. To tore a reading, press the ENTER key while on the main RUNNING SCREEN.
When readings are stored in memory, a symbol will appear on the main viewing screen.
When the memory is full, the Data symbol will ash. The stored data can be viewed by
scrolling through the logged readings using the UP and DOWN keys.
To delete the stored data:
1. Press and hold the ENTER key.
2. The TRASH CAN symbol will ash.
3. Continue to hold the ENTER key until the data is deleted.
4. Press the ESC key to exit to the MAIN MENU.
G2, G3
UNITS GasCheck instruments have the capability of displaying detected readings in a
variation of units: ppm, cc/s, mgm3, and g/yr.
Use the UP and DOWN keys to select the desired unit, and then press the ESC key to
exit to the MAIN MENU.
NOTE: the Custom Calibration routine automatically selects the type a calibration
depending on his setting. See 5.1 CALIBRATION.
• CC/SEC = cubic centimeters per second oers a volumetric leak rate that directly
measures the volume of a gas escaping from a given point. It is also known as ml/
sec (milliliters per second). The GasCheck can typically detect helium leaks down to
0.0005 of a cubic centimeter per second.
• PPM = Parts per million. This unit indicates a concentration but can’t be used to
quantify a volume of gas leakage.
• MG/M3 = Milligrams per meter cubed. Like ppm, this unit is also a concentration, so
it can’t be used to quantify a volume of gas leakage.
• G/YR = Grams per year oers an alternative volumetric leak rate that directly
measures the volume of a gas escaping from a given point.
G3
DISPLAY The GasCheck has the capability of displaying a cc/sec and g/yr reading in either
decimal or exponent form. (Readings in ppm and mg/m3 can only be displayed in
decimal form.)
To change the display:
1. Use the UP and DOWN keys to select the desired unit.
2. Press the ENTER key to display the next screen.
3. Use the UP and DOWN keys to select the desired display and then press the ESC key
twice to exit to the MAIN MENU.
G3
UPGRADE The GasCheck instrument can be upgraded using a simple upgrade code. This facility
allows the GasCheck to be upgraded instantly by the user in the eld. See Table 7:
GasCheck Feature Comparison to compare the various features within each model.
To upgrade a GasCheck, simply purchase an upgrade code from Portable Leak
Detectors, enter the 12-digit number on the upgrade screen using the UP, DOWN,
ENTER, and ESC keys. Once all 12 digits are entered correctly the instrument will
automatically switch o.
When the instrument is switched on, the new instrument model number will be
displayed.
G1, G2

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FUNCTION DESCRIPTION MODEL
GAS SELECTION The GasCheck is calibrated using helium gas at manufacture, however other gases
can be detected and measured using a gas table within the instrument. Although
GasCheck can’t dierentiate between gases, it can quantify other gases using
response factors stored in its internal gas table. Gas groups 0, 1, 2, 3, and 4 oer a
generic sensitivity.
See Table 8: Gas Sensitivity to compare response factors for specic gases. For advice
on gases not listed, please contact Portable Leak Detectors.
To select an alternative gas:
1. Use the UP and DOWN keys to select the desired gas
2. Press the ENTER key to conrm the selection.
3. A “tick” will appear.
4. Press the ENTER or esc to exit to the MAIN MENU.
If the gas to be detected does not appear in the instrument’s internal gas table,
then one of the ve Gas Groups can be selected. Gas Groups have a variation of
sensitivities. Group 1 is high sensitivity and Group 5 is low sensitivity. Gas groups allow
the instrument to calculate leak rates with reasonable accuracy.
Table 7: GasCheck Feature Comparison
FEATURE G1 G2 G3
CONTRAST X X X
BACKLIGHT X X X
SOUND X X X
PEAK HOLD X X
CUSTOM CALIBRATION X X
BATTERY TYPE X
DATA LOG X
UNITS OF MEASUREMENT X
GAS TABLE X
UPGRADE X X
Table 8: Gas Sensitivity
NAME ABBREV. MAX. SENS. CC/SEC MIN. SENS. CC/SEC
Hydrogen H27.7 E-6
Helium He 1.0 E-5
Refrigerant R12 R12 2.7 E-5 0.000027
Refrigerant R1301 R1301 2.4 E-5 0.000024
Refrigerant R134a R134a 5.8 E-5 0.000028
Refrigerant R22 R22 2.6 E-5 0.000260
Refrigerant R11 R11 3.2 E-5 0.000032

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NAME ABBREV. MAX. SENS. CC/SEC MIN. SENS. CC/SEC
Sulphur
Hexauoride
SF62.2 E-5 0.000022
Carbon Dioxide C024.0 E-5 0.000040
Methane CH42.9 E-5 0.000029
Argon Ar 3.5 E-5 0 .000035
Oxygen 022.9 E-5 0.000029
Refrigerant R502 R502 3.0 E-5 0.000030
Refrigerant R404a R404a 3.2 E-5 0.000032
Refrigerant R407c R407c 3.3 E-5 0.000033
Refrigerant R410a R410a 3.2 E-5 0.000032
Refrigerant R507 R507 3.8 E-5 0.000038
4. BASIC
OPERATION
All GasCheck G Series models have the same keypads. The following
section explains the general functionality of each key.

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4.1 STARTUP ROUTINE
1. When the GasCheck rst switches on, it will display its model number
and the gas that it has been calibrated with.
2. A second screen then displays the instrument’s serial number, the
instrument’s rmware version and web address.
3. A third screen appears to indicate the GasCheck is Zeroing it’s signal.
4. Once the Zero routine is complete, the instrument displays its running
screen and is ready for use.
4.2 USING THE GASCHECK G SERIES
WARNING: Before switching on the GasCheck, ensure the ambient air
is clean. The instrument automatically Zeros the sensor at
switch on. After the instrument has run through the start
up routine, adjust the instrument settings to the desired
levels. Check the instruments sensitivity using a CalCheck
or calibration kit.
1. Switch the GasCheck on by pressing the ON/OFF key. After the instru-
ment has completed its Zero routine, it will show its normal running
screen.
Ensure the instrument is on the X100 (times one hundred) range.
While on the main running screen, use the UP and DOWN key to adjust
between sensitivity ranges. X100 is the most sensitive, X1 is the least
sensitive.
2. Gas leaks tend to occur at pneumatic joints or welded seams. To
test for a leak, hold the GasCheck at a 45-degree angle to the object
being tested and drag the probe along the seam or joint at a rate of
approximately 25mm per second.
3. When a leak is detected, the bar graph will start to ll and the
frequency of the audio output will increase but will reduce as the
probe moves away from the leak. Return the probe to the suspected
leaking area and move slowly along the same area until the leak is
located. Once located, the probe should be held at the leak until the
numeric reading stabilizes.
4. The bar graph oers a graphical indication only and should not be
used to measure a leak. You many nd that the numeric reading will
continue to increases after the graph has completely lled. Should the
instrument detect a leak that is too large for the range selected, the
numerical screen will ash and display“9999”. Use the UP or DOWN
keys to adjust the instrument sensitivity.

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Variation in temperature, humidity, and background gas may result in a
constant level being detected on the instrument. To reset to Zero, hold
the instrument away from the source of contamination and then press the
ZERO key. The instrument’s display will return to a near Zero reading.
The following things will aect the instrument’s reading:
• CO2and moisture from the breath of the instrument user
• Barometric air pressure and background temperature
• Sources of cold and heat
4.3 PROBE OPTIONS
In some applications the gray probe cover may restrict access to the area
under test. The gray probe cover can be removed by pulling it o the
instrument. When the gray cover is removed, great care should be taken
when using the instrument. Note the following precautions:
• Do not remove the semi-transparent probe sleeve. This sleeve ensures
that the metal inner probe remains 1 mm from the surface of the test
area, avoiding accidental dirt and moisture ingress.
• Do not touch the probe, especially the brass sensor housing. Heat from
ngers can result in signicant changes in signal causing false readings.
• Avoid placing the probe on wet or dirty surfaces. Blockage of the probe
will result in instrument failure.
Figure 2: Changing Probes
Some applications may require a longer probe to gain access to pneumatic
joints and seams to be tested. The GasCheck is also supplied with a 300mm
probe that can be changed by the user.
To change probes, carefully do the following:
1. Switch the instrument to OFF.
2. Remove the outer gray probe cover (see 1).
3. Place the box wrench (supplied with the instrument) over the existing
probe so the spanner ts over the brass nut (see 2), and unscrew the
probe in a counterclockwise direction (see 3).
4. Withdraw the wrench and probe assembly (see 4).
To ret the short or the long probe, follow the steps above but in reverse
order.
CAUTION When using the box wrench to tighten the probe nut,
ensure the nut is rmly tightened. Do not use additional
tools; they may damage the tread.

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Should a probe become blocked, use dry, clean, compressed air to blow
out the blockage from the instrument end of the probe.
WARNING Ensure safety guidelines are adhered to when using
compressed air.
4.4 DETECTING LEAKS
Hold the GasCheck in one hand and draw the instrument probe along
the area to be checked at approximately 25 mm per second. When a
leak is detected, retrace the route of the probe at a slower rate until the
leak is located. Once located, hold the instrument over the leak until the
measurement stabilizes. The reading can be logged by pressing the
ENTER key.
Some readings may be larger than the instrument can detect and the
measurement units will be replaced by“99999” on the display. In this case,
use the UP or DOWN key to adjust the instrument sensitivity.
Figure 3: Detecting Leaks
When detecting very small leaks, probe movement at a rate of 10mm per
second may be required.
The outer gray probe cover can be removed to allow better access to
restricted areas. If the outer probe is removed, please note the following:
• Avoid bending the inner probe. A bent probe will aect accuracy.
• To prevent probe blockage, avoid placing the probe in liquid or dirt.
• Care should be taken to ensure the brass sensor housing component
remains at a constant temperature. Avoid touching the brass sensor
block with ngers.
• The GasCheck can detect changes in humidity and carbon dioxide.
Therefore, avoid breathing on the probe.
• The thin white tube that covers the inner probe should not be removed.
This tube ensures a 1mm gap is maintained between the probe and the
surface being tested.

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5. MAINTENANCE
5.1 CALIBRATION
The GasCheck G Series has two selectable calibration settings: factory
and custom. Factory calibration is carried out at Ion Science during the
instrument’s manufacture. It can be selected and used but cannot be
changed.
The GasCheck is calibrated against a 5000 ppm helium concentration and a
0.0005cc/sec (5 E-4) helium leak rate.
Custom calibration gives the user the ability to calibrate the instrument.
This setting may oer improved accuracy over the factory calibration if
the barometric air pressure diers from that stated on the instrument’s
calibration certicate.
5.1.1 SELECTING FACTORY OR CUSTOM CALIBRATION
To select either FACTORY CAL or CUSTOM CAL, select the calibration screen
and move the up use the up and down keys to move the “tick” under the
desired symbol, then press the ESC key to exit to the main menu.
Custom calibration can only be selected and used after the instrument has
been calibrated by the user. To do this, move the “tick” under the CUSTOM
CAL symbol and press the ENTER key.
The GasCheck requires either 5000 ppm helium concentration or a
0.0005cc/sec (5 E-4 cc/sec) leak rate as a reference. The GasCheck
automatically selects the type of calibration media based on which unit
the instrument has already selected.
If the GasCheck is used to detect leaks measured using “ppm or mg/m3”
units, then the instrument must be calibrated using a 5000 ppm helium
concentration.
If the GasCheck G is used to detect leaks measured using “cc/sec” unites,
the instrument must be calibrated using a 0.005 cc/sec (5 E-4) helium leak.
5.1.2 CALIBRATION PROCEDURE USING PPM UNITS
Please read this entire procedure before proceeding with this calibration
routine.
1. Fill an empty (uncontaminated) sample bag with 5000 ppm helium gas
before starting the calibration procedure. Also remove the outer gray
probe from the GasCheck.
2. Select the CUSTOM CAL symbol from the instrument’s menu. An
option appears allowing the adjustment of the“ppm” value to ensure
the instrument matches the gas concentration being used. Use the up
and down keys to adjust between 4900 and 5100 ppm.

LACO USER MANUAL - GASCHECK G SERIES
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© 2018 FLUIDX Equipment, Inc.
3. Ensure the instrument is in clean air and then press the ENTER key. The
instrument will Zero. This will take a few seconds, but once complete a
READY message will appear.
4. Insert the instrument’s probe fully into the sample bag containing
the gas and press the ENTER key. The instrument will automatically
sequence through the cold and hot stages of calibration but when
nished gives a summary of values.
5. Press the ENTER key to return back to the calibration option screen.
Press the ESC key to start using the instrument or press the ENTER key
to calibrate again.
NOTE To avoid errors in calibration, the following points should
be noted:
• Avoid bending the inner probe as this will aect the GasCheck’s accuracy
• The GasCheck can detect changes in humidity and carbon dioxide. Avoid
breathing on the probe.
• Avoid pressurizing the sample bag. This will cause signicant errors in
reading.
5.1.3 CALIBRATION PROCEDURE USING CC/SEC UNITS
Please read this entire procedure before proceeding with this calibration
routine.
1. Check your LACO CalMaster™ Leak Standard to ensure the pressure
reading matches the leak rate shown on the calibration stick. The
pressure gauge may be installed on your leak standard or for open
style leak standards the pressure gauge is set on helium regulator.
2. Select the CUSTOM CAL symbol from the instrument’s menu.
3. Ensure the instrument is in clean air and then press the ENTER key. The
instrument will Zero. This will take a few seconds but once complete, a
READY message will appear.
4. Insert the instruments probe into the CalMaster™ Leak Standard’s
outlet and press the enter key. The instrument will automatically
sequence through the cold and hot stages of calibration. When
nished, it gives a summary of values.
5. Pressing the ENTER key will return back to the calibration option
screen. Press the ESC key to start using the instrument or press the
ENTER key to recalibrate again.
NOTE The GasCheck can detect changes humidity and carbon
dioxide. Avoid breathing on the probe.