Gow-Mac 21-080 User manual

Operating Manual
Read instructions before operating
Model 21-080
Mini Gas Leak Detector
Model 21-080: 100 - 240 VAC, 50/60 Hz
June 2023
Rev. 0
ALLOW UP TO 7 HOURS FOR FULL CHARGE.
FULL RUNTIME WILL RETURN AFTER
SEVERAL CHARGE/DISCHARGE CYCLES.
277 Brodhead Road, Bethlehem, PA 18017-8600 U.S.A. Tel: [phone]
!
IMPORTANT
For new instrument right out of the box or one
that has not been used for quite some time:

GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
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GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
Contents
1-0 Model 21-080 Mini Gas Leak Detector .................................................................... 5
2-0 Specications ........................................................................................................... 5
3-0 Instrument Operation ............................................................................................... 6
3-1 User Interface Display and Controls .............................................................. 6
3-2 Operation .......................................................................................................... 8
4-0 Leak Checking Procedure........................................................................................ 9
5-0 21-080 Parameter Descriptions ............................................................................. 10
6-0 Troubleshooting...................................................................................................... 13
7-0 Charging the Cell / AC Operation.......................................................................... 14
8-0 Sensitivity................................................................................................................ 14
9-0 Replacement Parts List.......................................................................................... 15
NOTICE The information in this document is subject to change without notice.
GOW-MAC®INSTRUMENT CO. MAKES NO WARRANTY OF ANY KIND WITH REGARD TO THIS MATERIAL,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE. GOW-MAC®Instrument Co. shall not be liable for errors contained herein or
for incidental consequential damages in connection with the furnishing, performance, or use of this material.
This document contains proprietary information which is protected by copyright. All rights are reserved. No
part of the document may be photographed, reproduced, or translated into another language without the prior
written consent of GOW-MAC®Instrument Co.
The warranties made by GOW-MAC®Instrument Co. with respect to the product are voided if the product is
not used and serviced in accordance with the instructions in this manual.
Please protect yourself and your employees by following these operating instructions. We encourage our
customers to write or call for any additional information relative to the use or repair of this instrument.
Copyright© 2005-2023 by GOW-MAC®Instrument Co.
®GOW-MAC is a registered trademark of GOW-MAC Instrument Co., USA

GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
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GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
1-0 Model 21-080 Mini Gas Leak Detector
1-1 The GOW-MAC®Model 21-080 Gas Leak Detector is supplied with a
3.5 ft. sampling probe and a power supply with 5 ft. cord.
1-2 The instrument contains a thermistor-type thermal conductivity detector (TCD),
diaphragm pump, and a printed circuit board containing all microelectronic devices.
1-3 The Model 21-080 operates on 100-240 VAC, 50/60 Hz and three (3) internal
rechargeable Ni-MH cells. An audible tone generator is incorporated with a speaker
output. The audio signal permits the technician to test for leaks without visually
scanning the meter.
2-0 Specications
Detector Thermal Conductivity Cell with Thermistors
Visual Readout LCD display featuring adjustable brightness
Peak hold with adjustable duration
Pump Diaphragm type
Line Voltage 100-240 VAC, 50/60 Hz
Cell Three (3) Rechargeable Ni-MH – 1.2 V, 1900 mAh, 1.9 Ah
Cell Life Approximately 20 hours; Recharged to 90% of capacity in 5
hrs.; Low battery indicator; Very low battery shutdown
Ranges Low: x1 High: x10
Adjustable sensitivity for low and high ranges
Response time 3 seconds
Zero Auto zero with drift elimination and manual override
Audio Signal Audible Alarm with adjustable setpoint and volume
Dimensions 7.5” L x 4.1" W x 3.0" H
(19.0 cm x 10.4 cm x 7.6 cm)
Weight Instrument: 1.2 lbs (0.52 kg)
Charger: 0.6 lbs (0.28 kg)
Features Flash memory for saving settings
Microprocessor controlled
Operating Temp. Range 70 °F ± 20 °F (21 °C ± 11 °C)
Accessories Testing to a NIST-traceable standard

GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
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CAUTION
THE GOW-MAC GAS LEAK DETECTOR IS NOT
DESIGNED TO BE USED TO DETERMINE LEAKS
OF COMBUSTIBLE GASES. IT IS DESIGNED TO
DETERMINE LOW LEVEL LEAKS OF ANY GAS
HAVING A DIFFERENT THERMAL CONDUCTIVITY
THAN AIR. UTILIZING THIS PROPERTY, IT IS
THEREFORE NOT SPECIFIC TO ANY GAS OR
VAPOR. A COMBUSTIBLE GAS LEAK DETECTOR
SHOULD BE USED FOR THE DETERMINATION
OF COMBUSTIBLE GAS LEAKS IN POSSIBLE
HAZARDOUS CONDITIONS.
3-0 Instrument Operation
3-1 User Interface Display and Controls
HI
ZERO
LO
21-080 LEAK DETECTOR
MENU
1
3
2
4
5
6
Figure 3-1
3-1-1 LCD Display, 16 segments per row, two rows, controllable backlight
The display is the visual instrument output and user interface when the
control buttons are engaged. After power up and a 20 second warmup,
the default display shows X1 for the low gain sensing range and BATT
with 0 to 4 bars to indicate battery charge status. The bottom row shows
“Sensing” indicating that the instrument is operating in leak detection mode.
During the 20 second warmup period, all buttons including power are
disabled.

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GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
3-1-2 Power Button
 Pressbriey(shortpress)topoweron.Pressandholdfor1second(longpress)
topowero󰀨.UsethePowerbuttonwheninthemenutoscrollthroughinstrument
parameters.
3-1-3 ZERO/MENU Button
A short press of the ZERO/MENU button adjusts the output to zero which is neutral
signal from the detector. The signal direction is either positive, indicated on the
display as POS, or negative, indicated as NEG. The direction, POS or NEG,
is a function of the thermal conductivity of the leak compared to ambient air or
atmosphere. Gases, for example helium, with thermal conductivity greater than air
indicate as NEG. Gases, for example argon, with thermal conductivity lower than air
indicate as POS.
3-1-4 HI Button
Increase the instrument sensitivity or gain by a factor of 10. The range X10 is shown
on the display. Also use this button to increase a parameter value when in the menu.
3-1-5 Alarm/Backlight Button
 Pressthealarm/backlightbuttonbrieytoselectbetweenaudiblealarmONandOFF.
Use a long press of the alarm/backlight button to select between display backlight
ON and OFF. Backlight intensity is user-settable in the menu. Use the Alarm/
Backlight button when in the menu to scroll through instrument parameters.
3-1-6 LO Button
Decrease the instrument sensitivity or gain by a factor of 10. The range X1 is shown
on the display. Also use this button to decrease a parameter value when in the menu.
8
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Figure 3-2
3-1-7 Sample Probe and Inlet Tubing
Wand with internal tubing through which the internal pump draws the gas sample.
The pump is energized and therefore drawing sample all the time that the 21-080
power is on. Use care to prevent the probe inlet from getting submerged in water and
to prevent dust ingress. The probe can be snapped into the clip on the side opposite
the power jack to enable one-handed operation.

GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
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3-1-8 Reference Air Inlet
The hole next to the sample probe is connected to the detector. Ambient air that is
drawn through the detector is the reference for the sample measurement. The leak
magnitudesignalisgeneratedbythethermalconductivitydi󰀨erencebetweensample
picked up by the probe and ambient air pulled in at the reference air inlet.
Figure 3-3
3-1-9 Power Adapter Receptacle
Power for battery charging and for plugged in operation is connected to the power
adapter receptacle. Use only A/C power adapter/charger GOW-MAC part number
118-100 or the 21-080 can be damaged and its warranty voided.
3-2 Operation
3-2-1 Connect the power adapter plug to the receptacle on the side of the enclosure.
Connect the power adapter to a 100 to 240 VAC outlet. Allow up to 5 hours to charge
the internal battery.
3-2-2 Press the Power button. Short press switches power on and long press switches
powero󰀨.
3-2-3 Select LO or HI sensitivity.
LO range = X 1
HI range = X 10
NOTE: “Zeroing” appears on the display after selection of HI or LO, after exiting the
menu,andanytimetheMENU/ZERObuttonisbrieypressed.Zeroingindicatesa5
to 10-second period of zeroing the signal. Completion is indicated when “zeroing” is
replaced by “sensing”.
3-2-4 SignalzerocanbedoneatanytimebybrieypressingMENU/ZERObutton
(extended press of the MENU/ZERO button is the way to enter the 21-080 menu).
3-2-5 Activate the audible alarm to supplement the visual output on the display.
3-2-6 Areas to be tested must be free of oil, grease, paint, water, and other contaminants
that might mask a leak or be drawn into the sampling probe.
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GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
 3-2-7 Tolookforaleak,movethesampleprobeopeningtothetargetareaortting.
NOTE: to locate the smallest leaks on HI range, the user should wear a glove on the
hand holding the probe to isolate the user from the probe inlet.
3-2-8 Leak indication. Segments on the bottom row of the display appear when a leak
is detected. The number of segments from 1 to 16 illuminate in proportion to the
intensity of the signal which is proportional to the concentration of the sampled gas.
4-0 Leak Checking Procedure
CAUTION
EXTREME CARE SHOULD BE EXERCISED
WHEN THE PROBE IS USED AROUND
ELECTRICAL HEATERS, SWITCHES, ETC.
4-1 Care must be exercised to avoid exhaling of breath near the probe or instrument
housing itself. The carbon dioxide (CO2) exhaled can be drawn into the sample probe
or the reference air inlet of the leak detector and falsely indicate a leak.
4-2 If helium (He) is being checked, a leak indicates polarity NEG (negative). Most other
gases or vapors indicate POS (positive polarity). Polarity is on a function of the
sample (leak) gas's thermal conductivity relative to ambient air reference.
4-3 When checking for leaks, it is IMPERATIVEthatttingsorsuspectedleakareas
are DRY. If the area has previously been checked with a water based bubble type
solution and HAS NOT BEEN DRIED, low readings, as well as possible detector
contamination may occur. For example, the thermal conductivity of water vapor
willcounteractthesignalfromheliumleaks.Thenete󰀨ectwillbefalselowleak
indication.
MOISTURE
DO NOT ALLOW MOISTURE TO BE DRAWN
INTO THE PROBE!
4-4 Using the probe, carefully move the tip around and over suspected joints, seals,
seams, or other areas where leaks occur. The probe must be moved slowly to detect
small leaks.
4-5 A leak is indicated by illumination of display segments and by sound if the alarm
is enabled. Remove the probe from the area, allow the segments to settle to zero
(rezero if necessary), and return probe to the suspected location to verify the leak.
4-6 For more detailed information on leak detector sensitivity, refer Section 8-0
Sensitivity.

GOW-MAC Instrument Co. Model 21-080 Gas Leak Detector Rev. 0, 0623
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5-0 21-080 Parameter Descriptions
The 21-080 parameters are functions that can be changed in the menu.
21-080
Parameter Funcon Available range Default seng
Alarm volume Audible alarm sound
level 0 – 100 % 50 %
Alarm type Alarm enable and type
of tone
Select constant
tone, beeping
tone, or alarm o 
constant
Alarm set point Set threshold for
alarm sound
1 – 16 segments
of the display 10
Pump speed Air ow intake by the probe 0 – 100 % 50 %
Backlight LCD display backlight brightness 0 – 100 % 50 %
LO range
sensivity
Adjust sensivity within low
range 0 – 100 % 50 %
HI range
sensivity
Adjust sensivity
within high range 0 – 100 % 50 %
Peak hold on-o
The high signal
(maximum illuminated segments)
of a transient leak is marked by *
on the display
On or o on
Peak hold delay Time that the peak
indicator * remains displayed 0 to 999 seconds 20 sec
Auto zero on-o
Connuous adjustment of long-
term zeroing
(while signal is below 3 bars)
On or o on
Auto zero speed Rate of connuous adjustment 0 – 100 % 50 %
Restore sengs
Restore factory default sengs
Must
select YES and con  rm
YES to restore.
Yes or no no
Summary of 21-080 user-seable parameters