Bacharach Gas Pup Instruction

Gas Pup

®

Natural Gas &

Pressure Detection

Instruction 55-9002

Operation & Maintenance

Rev. 1 – December 2003

Product Leadership • Training • Service • Reliability

WARRANTY

Bacharach, Inc. warrants to Buyer that at the time of delivery this Product will be free from defects in material
and manufacture and will conform substantially to Bacharach Inc.’s applicable specifications. Bacharach’s
liability and Buyer’s remedy under this warranty are limited to the repair or replacement, at Bacharach’s
option, of this Product or parts thereof returned to Seller at the factory of manufacture and shown to
Bacharach Inc.’s reasonable satisfaction to have been defective; provided that written notice of the defect
shall have been given by Buyer to Bacharach Inc. within one (1) year after the date of delivery of this Product
by Bacharach, Inc.

Bacharach, Inc. warrants to Buyer that it will convey good title to this Product. Bacharach’s liability and
Buyer’s remedy under this warranty of title are limited to the removal of any title defects or, at the election of
Bacharach, to the replacement of this Product or parts thereof that are defective in title.

THE FOREGOING WARRANTIES ARE EXCLUSIVE AND ARE GIVEN AND ACCEPTED IN LIEU OF (I)
ANY AND ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE: AND
(II) ANY OBLIGATION, LIABILITY, RIGHT, CLAIM OR REMEDY IN CONTRACT OR TORT, WHETHER OR
NOT ARISING FROM BACHARACH’S NEGLIGENCE, ACTUAL OR IMPLIED. The remedies of the Buyer
shall be limited to those provided herein to the exclusion of any and all other remedies including, without
limitation incidental or consequential damages. No agreement varying or extending the foregoing warranties,
remedies or this limitation will be binding upon Bacharach, Inc. unless in writing, signed by a duly authorized
officer of Bacharach.

A Instruction 55-9002

To Register Your Warranty, Visit

www.bacharach-inc.com

Notice:

Product improvements and enhancements are continuous, therefore the specifications and information
contained in this document may change without notice.

Bacharach, Inc. shall not be liable for errors contained herein or for incidental or consequential damages in
connection with the furnishing, performance, or use of this material.

No part of this document may be photocopied, reproduced, or translated to another language without the prior
written consent of Bacharach, Inc.

Copyright © 2001-2003, Bacharach, Inc., all rights reserved.
BACHARACH

®

and Pup® are a registered trademarks of Bacharach, Inc.
All other trademarks, trade names, service marks and logos referenced herein
belong to their respective companies.

Declaration of Conformity

Manufacturer’s name: Bacharach, Inc.
Manufacturer’ address: 621 Hunt Valley Circle

New Kensington, PA 15068-7074

European operations: Bacharach Europe

Sovereign House, Queensway
Royal Leamington Spa
Warwickshire CV31 3JR
United Kingdom

Product name: Gas Pup

conforms to the following specifications:
European Directive 89/336/EEC
EN 50081-1: 1992 (Emissions)
EN 50082-1: 1998 (Immunity)
EN 61000-4-2: 1995 (Electromagnet)
EN 61000-4-3: 1995 (Electromagnet)

i

Gas Pup

Instruction 55-9002

Contents

Contents

Safety Information ....................................................................... iii

Introduction..................................................................................... 1

General Description ................................................................................1

Components .............................................................................................2

Natural Gas Detection .......................................................................2

Pressure Detection .............................................................................2

Sample Pump .....................................................................................2

Batteries .............................................................................................2

Case.....................................................................................................2

Control Panel Description ......................................................................3

Gas and Pressure Fittings ......................................................................4

Technical Characteristics............................................................. 5

Operation .......................................................................................... 6

Operating Precautions (Please Read) ....................................................6

Battery Installation.................................................................................7

Turning ON the Gas Pup........................................................................8

Turning OFF the Gas Pup ....................................................................10

Backlighting ..........................................................................................11

Battery Voltage Check ..........................................................................11

Gas Operating Mode .............................................................................11

Auto-Ranging....................................................................................12

Fixed HI% Range..............................................................................12

PPM Range .......................................................................................13

LO% (Low Percent) Range ...............................................................13

HI% (High Percent) Range...............................................................14

Pressure Operating Mode .....................................................................14

Selecting the Pressure Mode............................................................14

High Pressure Mode.........................................................................16

Low Pressure Mode ..........................................................................16

Delta Pressure Mode ........................................................................16

Using the Probe’s Filter Chamber........................................................18

Foam Filter Element – Particulate Filtration.................................18

Charcoal Filter – Petroleum Vapors vs. Combustible Gases..........18

Water/Filter Trap ..................................................................................20

Error Messages......................................................................................21

ii

Gas Pup

Instruction 55-9002

Contents

Calibration ..................................................................................... 22

Gas Calibration Equipment Setup .......................................................22

Gas Calibration Procedure ...................................................................23

Pressure Sensor Check .........................................................................27

Maintenance................................................................................... 28

Batteries ................................................................................................28

Sampling Probe .....................................................................................28

Gas Inlet Filter Replacement ...............................................................29

Pump Replacement ...............................................................................29

Combustibles Sensor Replacement ......................................................30

Leak Check Basics ................................................................................30

Parts & Service.............................................................................. 32

Replacement Parts ................................................................................32

Accessories.............................................................................................33

Service Centers .....................................................................................34

Safety

Safety is essential in the use and maintenance of Bacharach equipment.
Therefore this manual and any marking on the instrument provide
important safety information concerning the operation, care, and mainte­nance of this instrument.

All operating and maintenance personnel should read and understand the
contents of this manual before operating or maintaining the instrument.

Observe all of the safety information provided.

Safety Alert Symbol

This symbol together with the word WARNING or CAUTION is used to
call a user’s attention to hazards or unsafe practices that could result in
injury or property damage. The message that follows provides informa­tion for preventing or avoiding the hazard.

WARNING: Informs the user of hazards or unsafe practices that
if not avoided could result in severe personal injury or death.

CAUTION: Informs the user of hazards or unsafe practices that
if not avoided could result in personal injury or property damage.

Purpose of Manual

This instruction manual is intended to familiarize all personnel with the
safe operation and maintenance procedures for the Bacharach Gas Pup.

Please retain this manual for future reference.

Gas Pup Safety

iii

Instruction 55-9002

Notes:

iv Instruction 55-9002

Gas PupSafety

Instruction 55-9002 1

Gas Pup

Introduction

Introduction

General Description

The Bacharach Gas Pup (Figure 1)
is a natural gas detection instru­ment designed for general leak
detection, barholing operations,
regulator pressure checks, and line
pressure integrity operations. It
offers measurement of natural gas
(as methane) in the following three
ranges:

• PPM (Low) Range: Gas level
displayed in 0 to 2500 ppm as a
bar graph, allowing visual indica­tion of the peak reading. Useful
for locating leaks in piping.

• LO% (Mid Percent) Range:
Measures natural gas in the
range of 0.2–5.0% by volume,
which corresponds to the lower
explosive limit (LEL) of methane.

• HI% (High Percent) Range: 0–100% by volume is useful in “pin
pointing” leaks in underground piping through barhole testing

The Gas Pup also features three pressure modes: High (0 to 99 psig);
Low (–9.9 to 9.9 psig); and Delta (displays a pressure change in the range
of ±9.9 psig from any reference pressure between 0 and 90 psig).

Three ‘AA’ batteries power the instrument. Pressing the key for at
least 1 second turns the instrument ON; after which, the battery voltage
is briefly displayed, followed by the gas and pressure sensors being
zeroed, and then followed by the display of the detected gas level.

The Gas Pup’s gas display is auto ranging, automatically switching
between its PPM, LO%, and HI% ranges as the detected gas level rises
and falls. The Gas Pup’s pressure-operating mode is selected by pressing

the key while the word “GAS” is being displayed during the
instrument’s warm-up period.

Figure 1. Gas Pup shown with

Probe and Coiled Tubing

Gas Pup

2 Instruction 55-9002

Introduction

Components

Natural Gas Detection

The instrument’s PPM and LO% ranges use a catalytic-bead detection
circuit, which is the most widely accepted method of detecting combus­tible gases. The HI% range uses the thermal-conductivity method of
detection, which is a reliable method for measuring the concentration of
one gas in a second gas (methane in air).

Pressure Detection

The instrument contains a solid-state pressure sensor that supports the
instrument’s three pressure modes (High, Low & Delta). The optional
Pressure Hose Kit accessory with fittings (P/N 55-0038) can be used to
connect the instrument’s quick-connect pressure fitting to the pressure
source.

Sample Pump

An internal sample pump draws a gas sample into the instrument for
analysis. This is a convenience in the LO% and HI% gas ranges, providing
a more reliable and accurate test of gas levels. It is also important in the
PPM range to achieve a stable gas reading at low gas concentrations.

The sample pump includes a flow-failure function. If the flow is blocked
(e.g., clogged filter or crimped hose), the display will blink the letters
“F P” in the READING window. When the pump returns to normal
operation, the display stops blinking.

Batteries

Three ‘AA’ alkaline batteries supply power to the instrument. A fresh set
of batteries will typically last 6–8 hours, depending on how the instru­ment is used. The batteries are housed in a battery block internal to the
instrument, and are protected with a metal cover and retained by two
thumbscrews. This design allows the batteries to be quickly replaced in
an area known not to contain explosive gases.

Case

The instrument is housed in an anodized extruded aluminum case. The
instrument is rugged, resistant to water and electromagnetic interfer­ence. Rubber-bumper guards provide impact protection on both ends of
the instrument.

Instruction 55-9002 3

Gas Pup

Control Panel Description

Two pushbutton controls and a large LCD are conveniently located at the
top of the instrument. The backlit LCD provides highly readable indica­tions of natural gas or pressure in any lighting condition ranging from
direct sunlight to total darkness.

The control panel consists of the following three windows and two
pushbutton keys:

• READING Window: A two-digit display that is used to primarily display
the concentration of natural gas in the LO% and HI% gas ranges. The
READING window also displays pressure readings when the instru­ment is operating in any one of its three pressure modes.

Introduction

Figure 2. Controls and Indicators

Bar Graph Window
(active only in the HI%
and ppm ranges,
showing 25% gas)

READING Window
(showing 25% gas)

RANGE Window
(range pointer showing
that instrument is in its
HI% range)

Range Identifiers

Function Key

Power ON/OFF Key,
plus Backl ight ON/OFF

Gas Pup

4 Instruction 55-9002

• Bar Graph Window: Provides a real time moving display of the natural
gas concentration to give a better ‘feel’ of when the gas level has
reached a peak. The bar graph is active only in the PPM and HI%
ranges.

• RANGE Window: Identifies the range in which the instrument is
currently operating. This is accomplished by means of a pointer, which
in conjunction with range-labels printed on the display overlay, define a
range for the gas reading.

• Key: Turns the instrument, and also the backlight, ON and OFF.

• Key: Changes the instrument’s function as determined by its current
operating mode, thus allowing a variety of functions to be selected with

just one pushbutton. Refer to text in this manual’s Operating section for
details.

Gas and Pressure Fittings

Two quick-connect fittings (Figure 3) provide convenient connections to
the gas probe and pressure hose assemblies.

The gas fitting mates with a quick-connect female plug, while the pres­sure fitting mates with a quick-connect male plug.

Introduction

Figure 3. Gas and Pressure Fittings

Gas
Fitting

Pressure
Fitting

Instruction 55-9002 5

Gas Pup

Technical Characteristics

Measurement Ranges:

Natural Gas ........................... PPM: 0 to 2500 ppm

LO%: 0.2 to 5.0% volume gas
HI%: 0 to 100% volume gas

Pressure:

High .................................... 0 to 99 psig

Low...................................... ±9.9 psig referenced to atmospheric

pressure

Delta.................................... ±9.9 psig from any reference pressure

point between 0 and 90 psig

Accuracy:

Natural Gas ........................... PPM: (not applicable)

LO%: ±0.3% gas
HI%: ±3% gas

Pressure: ................................ ±5% of Reading

Warm Up Time ........................ 1 minute

Response Time:

Gas.......................................... <20 seconds to 95% of final value

Pressure ................................. <5 seconds to 95% of final value

Operating Environmental Conditions:

Temperature .......................... –4 to 122 °F (–20 to 50 °C)

Humidity ................................ 10 to 95% R.H. (non-condensing)

Air Pressure........................... 1 Standard Atmosphere, ±10%

Position .................................. Any

Storage Environmental Conditions:

Temperature .......................... –22 to 122 °F (–30 to 50 °C)

Humidity ................................ 10 to 95% R.H. (non-condensing)

Position .................................. Any

Size............................................ 4.7 x 2.3 x 3.7 in. (11.9 x 5.8 x 9.4 cm)

Weight ...................................... 25 oz (712 g)

Batteries .................................. Qty 3, ‘AA’ alkaline

Battery Life............................. Typically 6–8 hours of continuous opera-

tion, and well over a week of operation
when used from 50 to 60 minutes a day

Agency Approvals ................. MET lab certified to UL913 and CSA

C22.2-157, intrinsically safe for use in
Class I, Division 1, Groups A, B, C & D
hazardous areas

Technical Characteristics

Gas Pup

6 Instruction 55-9002

Operation

Operating Precautions
(Please Read)

To ensure that the gas sensor is properly zeroed at startup, the Gas Pup
must be turned on in fresh air (free of combustible gases or vapors).

Before using the Pup to detect gas, ‘bump test’ the instrument by apply­ing a known concentration of gas to the instrument’s gas inlet port, and
then observing that the instrument responds to the applied gas in a
positive manner. The optional Response Check Gas bottle (P/N 51-1816) is
recommended for this purpose.

Calibrate the instrument about every 30 days to assure its accuracy. The
frequency of calibration, however, may change depending on how often
the instrument is used and the amount of gas that was sampled. Create a
maintenance log to keep track of when an instrument was calibrated, and
then use this log to help develop a calibration schedule. For example, an
instrument that fails its calibration after only being calibrated a single
time should be calibrated more often.

Avoid sampling leaded gasoline vapors, or gases or vapors containing
silicones or sulfur compounds. Tetraethyl lead, silicones, and sulfur
compounds can form contaminating compounds on the sensor element
(poison the sensor), with resulting loss in sensitivity.

Always purge the instrument with fresh air after completing a test. This
removes combustibles from the sensor chamber and prolongs the life of
the sensor.

Operation

Instruction 55-9002 7

Gas Pup

Operation

Battery Installation

WARNING: Explosion hazard:

• To reduce the risk of igniting a flammable atmosphere,
batteries must only be changed in an area known to be
non-flammable.

• To maintain agency approval, use only the following types of
‘AA’ alkaline batteries: Energizer E91; Duracell MN1500 or
MX1500; Rayovac 815; and Panasonic AM-3PI.

1. Loosen the two thumbscrews on battery cover and remove cover.

2. Insert three ‘AA’ batteries into the Pup, observing polarity as shown
in Figure 4.

3. Reinstall battery cover and tighten its thumbscrews.

Figure 4. Battery Installation

LOOSEN BOTH BATTERY
COVER THUMBSCREWS

‘AA’ BATTERIES

Gas Pup

8 Instruction 55-9002

Turning ON the Gas Pup

Important! To assure that all detectors are properly zeroed, the

Gas Pup must be turned on in a gas-free environment (no
combustibles), and that no pressure is being applied to the
instrument’s pressure port.

It is also recommended that the probe and hose assembly be
connected to the instrument before turning it on.

Refer to Figure 5. The Gas Pup is turned ON by momentarily pressing the

key for 1 second. Listen for the pump to start and observe that all
segments of the display are momentarily turned on. After all segments
have been displayed the word “UEr” (Version) is displayed followed by the
instrument’s software version number. Next, the letter “b” appears in the
RANGE window along with the battery voltage momentarily appearing in
the READING window. The instrument will quickly move to display the
word “GAS”, indicating that the instrument is operating in its gas mode.

After several seconds, the READING window will display a flashing “AS”
(Auto Start). This is the Auto Start portion of the instrument’s operation,
and is used to stabilize the gas sensor in order to establish ‘zero’ gas
readings. Without additional operator intervention, the auto start portion of
the start-up routine will finish, leaving the instrument in its PPM gas range.

Operation

Instruction 55-9002 9

Gas Pup

Figure 5. Turning ON the Gas Pup

Operation

Battery Voltage

Mode Display

RANGE

Flashing Display /

Auto Start Sequence

PPM Gas Display

LCD Segment Test

UEr (Version)

Software Version

Gas Pup

10 Instruction 55-9002

Turning OFF the Gas Pup

Pushing and holding down the key initiates the instrument’s turn-off
sequence.

At first the battery voltage is displayed, followed in about 1 second by the
letters “OFF” scrolling across the screen. The screen will go blank shortly
after all three letters are displayed.

Release the key as soon as the display goes blank.

Figure 6. Turning OFF the Gas Pup

Operation

Release button when
OFF disappears

Press and hold
down button

Instruction 55-9002 11

Gas Pup

Backlighting

Backlighting of the LCD allows a user to see the display in darkened
areas. Be aware that backlighting causes a higher battery drain and
should only be used when needed. To conserve battery life, the backlight
is automatically disabled when the battery voltage falls below 2.2 volts.

To activate the backlight, briefly press the key. The backlight will turn
ON along with the battery voltage being displayed for about one second.
The backlight automatically turns OFF after 5 minutes, or it can be
immediately turned off by again briefly pressing the key.

Battery Voltage Check

Battery voltage can be displayed by briefly pressing the key. Note that
this action also turns on the backlight.

Battery voltage is displayed in terms of the voltage available at the
printed circuit board from the battery source. The nominal voltage ranges
from approximately 2.8 volts to a minimum of 1.9 volts. Although the Gas
Pup will operate down to 1.9 volts, the last portion of the voltage curve is
quite steep. It is recommended that, except for short tests, the batteries
be replaced when the reading drops to less than 2.0 volts.

Gas Operating Mode

This is the default operating mode when no mode selection is made at
startup.

With the probe and hose assembly connected to the Gas Pup’s gas inlet
fitting, begin checking for gas by placing the probe tip into the area to be
tested. Wait approximately 15 seconds, and then observe the detected gas
level on the instrument’s LCD. The Gas Pup will display the detected gas
level in one of three ranges: PPM (0–2500 ppm), LO% (0.2–5.0%), and
HI% (0–100%).

WARNING: Explosion hazard. Should the display indicate a gas
reading near 5% (equivalent to 100% LEL), the instrument is
sampling from an area with a potentially explosive concentration
of gas. Take all necessary precautions to prevent ignition. Also,
if the detected gas concentration is above 15%, which is nor­mally considered too rich to be explosive, the concentration
around the area sampled may be within the explosive range and
should be considered dangerous.

Operation

Gas Pup

12 Instruction 55-9002

After checking for gas, allow the instrument to sample fresh air until the
LCD shows a very low ppm reading. This will help prolong sensor life by
purging the sensor chamber of combustible gas.

Auto-Ranging

The Gas Pup incorporates an auto-ranging
function that automatically switches the
display between ranges when a range limit is
reached. This avoids manual switching, and
assures, in conjunction with the range display,
that accurate readings are provided at all
times. The range selected by the instrument is
indicated by a pointer that appears in the
RANGE window (see Figure 7).

When a reading in the PPM range exceeds
2,500 ppm (equal to 0.25% by volume, bar
graph at full scale), the display will automati­cally switch to the LO% range, covering from

0.2% to 5.0%. This change will be instanta­neous. But if the reading is close to 2,500 ppm,
observe that the display may flicker between
ranges for a few seconds.

When the LO% reading exceeds 5.0%, the
display automatically transfers to its HI% range. This transfer takes a
few seconds to allow the detector to stabilize in the new range.

Auto-ranging from HI% to LO% occurs when the reading falls below 5.0%
for more than 5 seconds. The 5-second delay is to prevent nuisance range
transfers.

Fixed HI% Range

Manual selection of the HI% range may be
made to avoid any delay caused by auto-ranging
(for example in barhole testing), and to retain
the highest reading shown on the bar graph. To
lock the instrument in its HI% mode, momen­tarily press the key. Once auto-ranging has
been overridden, the instrument will remain in
the HI% range until the key is pushed again.

Operation

HI%

LO%
PPM

RANGE

HI%

LO%
PPM

RANGE

HI%

LO%
PPM

RANGE

PPM Range

LO% Range

HI% Range

Figure 7.

Range Display

HI%

LO%
PPM

RANGE

HI% Range

Figure 8.

Fixed High Range

Instruction 55-9002 13

Gas Pup

PPM Range

After the Gas Pup has been turned on, it
will default to its PPM range, showing
nothing or some portion of a bar graph
display. The range window will show a
pointer to the “PPM” flag for range defini­tion. Any low levels of gas will be shown by
a moving bar graph, which is logarithmic
providing a much higher response at the
low end of the scale. No numerical display
is provided in this range, as its primary
purpose is to locate a small leak rather than
to measure a gas concentration. Full scale
on the PPM range is 2,500 PPM or 0.25% by
volume. 500 PPM is about mid-scale, while
1,000 PPM is about ¾ scale.

LO% (Low Percent) Range

When the gas concentration increases
beyond the upper limit of the PPM range,
the display automatically switches (auto­ranges) to the LO% range, showing a two­digit value with one decimal place. This
range of the instrument is used for detect­ing gas concentrations that may approach
the explosive level. Natural gas may cause
an explosion if the concentration is around
5% by volume in air. This is referred to as
the Lower Explosive Limit (LEL) of gas,
and represents an extreme hazard. The
range indicator points to the “LO%” flag for
range definition. The reading will track
current concentration with a numerical-only display. This approach is
used to provide a numerical readout where readings are significant and
documentation of readings may be required. Auto switching from PPM to
LO% is instantaneous. Switching from LO% to PPM, however, may be
accompanied by the display momentarily flickering between the bar­graph-only display (PPM range), and the numerical-only display (LO%
range). This flickering should be brief.

Operation

Figure 9.

Typical PPM Reading

Showing 500 PPM

Figure 10.

Typical LO% Reading

Showing 2.5% Gas

Gas Pup

14 Instruction 55-9002

HI% (High Percent) Range

If the gas concentration goes above the
upper limit of the LO% range (greater than

5.0%), automatic changeover to the HI%
range occurs. The instrument goes through
a 5 second stabilization time period after
this range change occurs, with the display
flashing as an indication that the readings
are inaccurate until stabilized.

In the HI% range, there is a two digit
numerical display, with no decimal point,
plus a bar graph that tracks the digital
reading. The range indicator points to the
“HI%” flag for range definition. The number
displayed is the concentration of natural
gas being sampled in steps of 1% by volume.
Note that because there is only two digits,
100% gas is displayed as “– –”. The bar
graph tracks the digital reading to give an
enhanced visual picture of the changing gas
concentration, but the highest bar ‘sticks’ at
the maximum reading.

As noted above, a unique feature of the HI%
range is that the bar graph ‘sticks’ at the
maximum reading, a convenience in barhole
testing where the peak value is desired.
This peak value is retained until the instru­ment transfers (automatically or manually)
to the LO% range.

Pressure Operating Mode

Selecting the Pressure Mode

See Figure 12. The instrument is placed in its pressure mode by pressing
the key during startup while the word “GAS” is displayed. The display

changes to “PrS” to indicate that the pressure mode has been selected.
Then after the instrument warms up, the letter “P” appears in the
RANGE window, indicating that the instrument is currently measuring
pressure.

Figure 11.

Typical HI% Reading

Showing 38% Gas and

100% Gas

Operation

38% Gas

100% Gas

Instruction 55-9002 15

Gas Pup

Figure 12. Selecting the Pressure Operating

Mode During Startup

Operation

Important! Ensure that the instrument’s pressure port is open to
the atmosphere during startup, otherwise incorrect pressure
readings may result.

Before making a pressure measurement, tubing must be connected
between the gas source and the instrument’s pressure port. Depending on
the application, use the tubing and hardware supplied in either the
optional Pressure Hose Kit (P/N 55-0038) or Service Line Pressure Test­ing Kit (P/N 55-0072) to make this connection. Refer to the Accessories
section of this manual for a description of these options.

Gas Pup

16 Instruction 55-9002

High Pressure Mode

CAUTION: Maximum over pressure without damage is
150 psig.

The high-pressure mode measures pressure
in the range of 0 to 99 psig. Enter this mode
by first selecting the pressure mode during
startup as previously described. The instru­ment will default to its high-pressure mode
as signified by the letter “P” appearing in the
RANGE window. The READING window
will display the pressure applied to the
instrument’s pressure port. Note that an out­of-range pressure condition is signaled by two
dashes “–.–” appearing in the READING
window.

Low Pressure Mode

The low-pressure mode measures pressure in
the range of 0 to 9.9 psig, and also negative
pressures down to –9.9 psig. Enter this mode
by first placing the instrument into it high­pressure mode as previously described. Then
press the key to switch to the low-pressure
mode as indicated by the letter “d” appearing
in the RANGE window. The READING window will display the pressure
applied to the instrument’s pressure port. Positive pressure readings are
indicated by a steady display, while negative pressures are indicated by a
flashing display. Note that an out-of-range pressure condition is signaled
by two dashes “–.–” appearing in the READING window.

Delta Pressure Mode

The delta pressure mode is used to measure the delta (difference) in
pressure, and is useful when pressure proving new or repaired piping
that has been pressurized with compressed air.

Do the following to pressure prove a piping system (see Figure 14):

1. Attach the components of the optional Service Line Pressure Testing
Kit (P/N 55-0072) between the piping being tested and the
instrument’s pressure port.

2. Set up the Pup to measure high pressure as previously described
under the heading High Pressure Mode.

Operation

Typical High-Pressure

Reading

Typic Low-Pressure

Reading

Figure 13. High & Low

Pressure Modes

Instruction 55-9002 17

Gas Pup

Figure 14. Pressure Proving a System

using the Delta Pressure Mode

To piping system
being tested

PRESSURE
FITTING

HI%

LO%
PPM

®

RANGE

NATURAL GAS

READING

Attach a hand pump or air compressor
and pump up piping system to desired
pressure (not to exceed 99 psig) with
instrument in its high-pressure mode

SERVICE LINE
PRESSURE TESTING KIT
P/N 55-0072

3. Attach a hand pump or air compressor to the tire-valve portion of the
Testing Kit’s Tee, and then pump up the system to the desired pres­sure (not to exceed 99 psig).

4. Press the key until the letter “d” appears in the RANGE window,
indicating that the Gas Pup is now operating in its delta pressure
mode. The value “0.0” should now appear in the READING window,
indicating that the pressure being measured equals the high-pressure
reading just taken.

Note: The delta and low-pressure modes are activated in the
same manner. The difference being that the low-pressure mode
is entered while the instrument’s pressure port is open to the
atmosphere, while the delta mode is entered with pressure
already applied to the instrument.

5. Monitor the value in the READING window. The value displayed
indicates the difference in pressure (in the range of ±9.9 psig) between
the current reading and the initial pressure measurement. Positive
pressure readings, probably due to a rise in temperature, are indi­cated by a steady display, while negative readings that are due to
leaks are indicated by a flashing display. Note that an out-of-range
pressure condition is identified by two dashes “–.–” appearing in the
READING window.

Operation

Gas Pup

18 Instruction 55-9002

Operation

Using the Probe’ s Filter Chamber

The standard 10" probe supplied with the Gas Pup has a built-in filter
chamber that can hold either a foam filter element, or a charcoal filter
pack. Install and use these filters as follows:

Foam Filter Element – Particulate Filtration

When sampling, it is good practice to keep a foam filter installed inside
the probe’s filter chamber (see Figure 15). Although the instrument’s gas
inlet already has an internal particulate filter, the probe’s foam filter will
prevent dirt particles from building up inside the hose, which could
eventually cause a flow restriction, and where the dirt particles would be
difficult to remove for cleaning. Filters are packed ten to a box, and are
available as P/N 5500-7100.

Charcoal Filter – Petroleum Vapors vs. Combustible Gases

By using a disposable charcoal filter pack, it is a simple matter to distin­guish between an indication caused by combustible gases (from a pipeline
leak, for example) or an indication caused by a source of petroleum vapors
(such as a nearby gasoline station). Activated charcoal will absorb a
portion of the petroleum vapors in a gas sample; however, it will allow a
dry combustible gas (such as natural gas or propane) to pass through.
Filters are packed ten to a box, and are available as P/N 5500-7400.

Figure 15. Foam Filter Element

Instruction 55-9002 19

Gas Pup

The petroleum absorbing property of the activated charcoal filter is used
to detect petroleum based gases and vapors in the following way:

1. With a standard foam filter installed in the probe’s filter chamber,
take a gas sample and note the display indication.

2. Remove the foam filter and install in its place one of the small acti­vated charcoal filter packs. See Figure 16.

Note: The charcoal pack will increase the response time of the
instrument. Therefore, draw a sample of gas through the instru­ment for at least 60 seconds before taking a reading.

3. Take a second gas sample from the same area, and note if the indica­tion is less than it was in Step 1. If the indication has dropped, this
means that the charcoal has probably absorbed petroleum vapors, and
that one cause of the lower indication is likely to be petroleum vapors.

WARNING: Following the use of a charcoal filter pack, the pack
should be removed from the probe and discarded. Otherwise,
the presence of combustible vapors may not be detected in
subsequent testing.

Figure 16. Charcoal Filter Pack

Operation

Gas Pup

20 Instruction 55-9002

Operation

Water/Filter Trap

The optional water/filter trap accessory is recommended to be used in
conjunction with the 30" barholing probe; thus preventing water from
being drawn into the instrument when the probe is inserted into a hole
filled with water. The water trap can also be used with the standard 10"
probe when an operator is probing for a gas leak in an area that contains
pools of water.

Install the water/fiter trap directly on the instrument’s gas inlet fitting;
then connect the gas probe and hose assembly to the water trap as shown
in Figure 17.

When using the water trap, observe that its bowl will begin to fill as
water is drawn into the probe. It is good practice not to allow the water
level to rise above the filter retainer. Empty the bowl by first turning
OFF the Pup or removing the water/filter trap from the instrument, and
then pushing up on the drain valve located at the bottom of the bowl.

The water trap also contains a particulate filter that should be changed
when it becomes contaminated with dirt. Note that a dirty filter will slow
down the flow of gas into the instrument and thus slow down the
instrument’s response time. Replace this filter by first unscrewing the
bowl, and then unscrewing the filter retainer and discarding the old filter.
Install a new filter and reattach the bowl.

Figure 17. Water/Filter Trap

Attach Water/Filter Trap
to the Instrument’s
Gas Inlet Fitting

BOWL
(It is good practice not to
allow the water level to rise
above the Filter Retainer,
otherwise gas flow may
become restricted.)

PARTICULATE FILTER
(P/N 07-1644)

FILTER RETAINER
DRAIN

(Do not drain bowl with Pup
turned ON, otherwise water may
be drawn up into the instrument.)

Gas Probe & Hose Connector

Instruction 55-9002 21

Gas Pup

Error

Messages

2.3.0.

2.3.1.

2.3.2.

2.4.2.

2.4.8.

2.5.1.

2.5.2.
F P

CAL

Meaning

Stable level of calibration gas
was not detected within 50
seconds during calibration.

Calibration gas was not
detected during calibration.

Gain increase since last
calibration was greater than
50%.

Zero offset point for sensor is
too low.

Failure to write calibration
value to EEPROM.

Instrument failed to zero the
combustibles sensor within
4 minutes.

Low-battery condition.
Pump not running at proper

speed.

Instrument not calibrated.

Error Messages

The following is a list of error messages that may appear when operating
the Gas Pup. Note that numerical messages appear just prior to the
instrument turning itself off. Contact your nearest Bacharach Service
Center for assistance if the suggested remedies do not restore the instru­ment to normal operation.

Remedies

Ensure that a sufficient
amount of calibration gas
is being applied.

Apply calibration gas
when required.

Replace combustibles
sensor.

Replace combustibles
sensor.

Return instrument to
Bacharach for repair.

Replace sensor.

Replace batteries.
Blocked or insufficient

gas flow through instru­ment due to a pinched
hose or clogged inlet filter
(see Fig. 23). Instrument
may be too cold.

Calibrate instrument.

Operation

Gas Pup

22 Instruction 55-9002

Calibration

Calibration

It is recommended that the Gas Pup be calibrated by your nearest
Bacharach Service Center. Calibration, however, can be performed in the
field if your facility has the necessary equipment and qualified personnel
to perform the procedures described in the following sections.

Gas Calibration Equipment Setup

The following equipment is recommended to calibrate the Gas Pup (refer
to the Accessories Section for part numbers):

• Calibration Kit (includes gas regulator, tubing, and instrument fitting)

• Calibration Gas:

- Zero Air (20.9% Oxygen, balance Nitrogen) (optional)

- 2.5 ±0.05% methane

- 100 ±2% methane

WARNING: If you are not using Bacharach’s calibration kit, be
sure not to apply pressure to the gas inlet from your own
calibration equipment. Use the excess flow calibration method,
otherwise incorrect gas readings may occur.

Connect the components of the calibration kit, calibration gas cylinder,
and Gas Pup together as shown in Figure 18. DO NOT connect the Gas
Inlet Fitting to the Pup until instructed to do so in the calibration procedure.

Figure 18. Calibration Equipment Setup

TUBING

*

CALIBRATION-GAS CYLINDER

2.5% or 100% Methane
(See Accessories Section
for Part Numbers)

*Part of Calibration Kit

GAS INLET FITTING*

(Do not connect
until “AC” is displayed
in READING window)

HI%

LO%
PPM

®

RANGE

NATURAL GAS

READING

ON-DEMAND
GAS REGULATOR

*

Instruction 55-9002 23

Gas Pup

Gas Calibration Procedure

The Gas Pup has an auto-calibration feature that ensures proper calibra­tion of the instrument. After setting up the calibration equipment as
previously described, proceed with the calibration procedure as follows:

1. Before turning ON the instrument, be sure that the calibration
equipment is not connected to the instrument, and that the instru­ment is in an area of fresh air.

Important! Calibration should be performed in an area of fresh
air. If the quality of the surrounding air is unknown, then zero air
should be applied to the instrument's gas inlet port before the
instrument is turned on and allowed to flow during the auto-start
sequence (flashing “AS” in the READING window). This will
require a second regulator to be connected to a zero-air cylinder.

2. Press the key to turn ON the Pup. Before proceeding to Step 3,
wait until the instrument enters its auto-start period (flashing “AS”
appears in the READING window).

3. See Figures 19 and 20. Auto calibration is started by pushing
the key at any time while “AS” is being displayed. Observe that the
letter “C” appears in the RANGE window, indicating that the instru­ment is ready for calibration at the conclusion of the auto-start
sequence. Calibration gas must not be supplied to the instrument
before this time, or the sensor’s zero setting will be in error.

4. Following the auto-start period, the instrument will display a steady
“AC” for about 10 seconds and display “L” (for LO%) in the RANGE
window. The default range is LO% (Figure 19), but if you are calibrat­ing the HI% range (Figure 20), then press the key until “h” is
displayed.

WARNING: In the following steps, be sure to apply the correct
concentration of gas for the range being calibrated as listed
below. Failure to apply the correct gas will cause inaccurate gas
readings.

• LO%: apply 2.5% gas while showing “L” in the RANGE window

• HI%: apply 100% gas while showing “h” in the RANGE window

Calibration

Gas Pup

24 Instruction 55-9002

Calibration

Note: If zero air is being applied at this time, remove it before
proceeding to Step 5.

5. While a steady “AC” is being displayed, apply calibration gas by
simply connecting the tubing from the calibration equipment to the
Pup’s gas-inlet fitting. The on-demand gas regulator will automati­cally begin to supply the correct amount of calibration gas to the
instrument.

6. As the calibration gas is being applied, “AC” will begin flashing until a
steady gas value is detected for a period of 5 seconds, after which the
display will change to the calibration setting (2.5% for the LO% range,
or 100% for the HI% range). At this time the calibration gas may be
removed.

The instrument’s programming contains safeguards to prevent inaccurate
calibration, or to limit the use of a sensor that may require replacement
due to imminent failure.

Should calibration gas not be applied within the calibration period of
10 seconds, the instrument will drop out of the autocal mode and turn off
(error code 2.3.1 is displayed just before the instrument turns off). The
instrument is turned off to attract the users attention and make it evi­dent that a proper calibration had not been achieved. The prior calibra­tion values will be maintained to prevent an unintended change to these
values.

Instruction 55-9002 25

Gas Pup

Figure 19. Performing a LO% Calibration

Steady Display

Apply 2.5% gas now

Flashing Display Flashing Display

Remove gas

Fashing Display

During Calibration

Calibration

Gas Pup

26 Instruction 55-9002

Calibration

Figure 20. Performing a HI% Calibration

Steady Display

Apply 100% gas now

Remove gas

Flashing Display Flashing Display

Flashing Display

Flashing Display

During Calibration

Instruction 55-9002 27

Gas Pup

Pressure Sensor Check

The pressure sensor does not require calibration, but it is recommended
that the sensor be checked for accuracy on a periodic basis and to assure
that it is still operational.

To check the pressure sensor, the following equipment is recommended:

• Pressure source of at least 50 psig with an attached adjustable regula­tor (compressed-air cylinder, company gas, or shop air)

• Pressure measuring device (calibrated gauge, or digital manometer)

• Pressure Hose Kit (P/N 55-0038)

• Assortment of hardware: Tubing, Clamps, and Fittings

Check the pressure sensor as follows:

1. Connect the above equipment as shown in Figure 21.

2. Turn Pup ON and select its high-pressure mode as described under
the previous heading Pressure Operating Mode.

3. Adjust regulator of pressure source for a pressure gauge reading of
50 psig. Observe that the pressure reading on the Pup should be
within ±5% of the reading on the gauge.

4. Shut off regulator and disassemble test equipment.

Figure 21. Pressure Testing the Sensor

PRESSURE
SOURCE
(Compressed Air
Cylinder,
Company Gas,
or Shop Air)

PRESSURE
FITTING
(Do not apply pressure
until “P” is displayed
in READING window)

HI%

LO%
PPM

®

RANGE

NATURAL GAS

READING

PRESSURE HOSE KIT
OPTION (P/N 55-0038)

0

1

0

2

0

3

0

4

0

5

0

6

0

7

0

8

0

9

0

1

0

0

CALIBRATED PRESSURE GAUGE
OR DIGITAL MANOMETER

ADJUSTABLE
REGULATOR

TEE

Use clamps or fitings on all tubing
connections to prevent the
tubing from blowing off when
under pressure.

NOTE:

Calibration

Gas Pup

28 Instruction 55-9002

Maintenance

Maintenance

Batteries

The battery voltage is monitored by the instrument’s microprocessor, and
can be checked by momentarily pressing the key. Refer back to the
previous section Battery Voltage Check.

Battery replacement is recommended when the voltage at startup is less
than 2 volts. The batteries must be replaced when the display starts
blinking every five seconds while showing “b” in the RANGE window.

To replace the batteries, refer back to the previous section Battery

Installation.

Sampling Probe

The sampling probe is the most likely candidate for maintenance as it is
subject to damage in normal field operations. The probe tube may be
made of either aluminum or clear polycarbonate.

Replacing either probe is a simple matter of unscrewing the damaged
probe and installing a new one. Replace the O-ring if it looks deformed
and can no longer provide an air-tight seal. See Figure 22.

Figure 22. 10" Sampling and 30" Barholing Probes

10" Aluminum Probe Tube
w/ Filter Chamber

O-Ring

30" Polycarbonate or Aluminum
Barholing Probe Tube w/ Filter Chamber

Instruction 55-9002 29

Gas Pup

Maintenance

Gas Inlet Filter Replacement

Periodically check the gas inlet filter, located directly behind the gas-inlet
fitting, for signs of dirt. As necessary, replace this filter per Figure 23.

Pump Replacement

The pump may become inoperative due to water or solid particles getting
into the valves. This will require replacement of the pump to correct.

To replace the pump (see Figure 24):

1. Remove the instrument’s bottom plate using a 5/64" Allen wrench to
remove the plate’s four corner screws. Then remove plate and rubber
bumper to expose the instrument’s interior.

2. Back off the pump bracket screw in the lower corner of the flow block
and rotate bracket arm to free pump.

3. Unplug pump connector from printed circuit board and lift pump
straight out of instrument.

4. Install the new pump by lining up the pump’s inlet and outlet tubes
with the two flow block holes and pushing into place. Swing bracket
arm over pump and tighten—aligning pump as necessary.

5. Leak test pump before use per section Leak Check Basics.

Figure 23. Gas Inlet Filter Replacement

INLET FILTER
(P/N 55-0045)

Gas Pup

30 Instruction 55-9002

Combustibles Sensor Replacement

If the instrument cannot be calibrated in either range, the combustibles
sensor must be replaced with a new unit.

To replace the sensor (see Figure 24):

1. Remove the instrument’s bottom plate by using a 5/64" Allen wrench to
remove the plate’s four corner screws. Then remove the plate and
rubber bumper to expose the instrument’s interior.

2. Remove pump connector, pressure sensor connector, and multi-pin
connector from printed circuit board, noting orientation of connectors.

3. Remove three screws from printed circuit board; then carefully pry
the board straight up from flow block. The gas sensor is the silver
cylindrical piece in the center of the circuit board.

4. Gently pull sensor from circuit board and replace with a new unit.
Make sure that the sensor is firmly seated in receptacles and bot­tomed on circuit board.

5. Reinstall printed circuit board into flow block; taking care to properly
position the board as shown in Figure 24.

6. Replace three screws and tighten to hold board. Reattach the pump,
pressure sensor, and multi-pin connectors to the circuit board.

7. Leak check the assembly per the following section Leak Check Basics.

8. Calibrate the instrument per the previous section Calibration. Note
that if a new sensor is installed without performing a calibration, the
word “CAL” will appear when the instrument is turned on, alerting
the operator that the instrument needs to be calibrated.

Leak Check Basics

The easiest method to perform a leak check is to close off the sample inlet,
and then observe that a pump failure occurs. For example, to close off the
standard 10" probe, either grip its end tightly with your hand, or cover
with masking tape. Note that attempting to close off the fitting ends may
be not be successful, as there are leak paths when the hose is not in place.

Maintenance

Instruction 55-9002 31

Gas Pup

Maintenance

Figure 24. Pump or Sensor Replacement

FLOW B LOCK

COMBUSTIBL ES
SENSOR

WAVE WASHER

PRINTED CIRCUIT
BOARD SCREW
(3 PLACES )

PUMP BRACKET
SCREW

PUMP BRACKET

PUMP

MULTI-PIN
CONNECTOR

PUMP
CONNECTOR

PRESSURE
SENSOR
CONNECTOR

PUMP
BRACKET

PUMP

Gas Pup

32 Instruction 55-9002

Parts & Service

Part s & Service

Replacement Parts

Gas Pup Instrument Kit: includes instrument, 10" gas probe,
coiled gas tubing with quick-connect fittings, 2 inlet filters,

3 batteries, and a pocket size pressure & gas conversion card. ...... 55-8000

Battery Cover Assembly.................................................................... 55-0013

Bottom Plate ...................................................................................... 55-0010

Bracket, Pump ................................................................................... 55-0018

Bumper, Rubber ................................................................................ 55-0011

Filter, Gas Inlet, 100 micron, (package of 2).................................... 55-0045

Gas Hose Assembly............................................................................ 55-0043

Hose, Coiled ................................................................................... 55-0032

Quick-Connect Fitting, Female....................................................103-5402

Gas Probe Assembly .......................................................................... 55-3000

Probe Tube w/ Filter Chamber, 10" ...........................................3474-1350

O-Ring, 11/16" ID x 13/16" OD ............................................................ 05-5116

Pump Assembly ................................................................................. 55-0061

Quick Connect Fittings (on instrument):

Pressure:

Fitting, Quick Connect, Female ...............................................103-5408

Gas:

Fitting, Inlet............................................................................... 55-0015

Fitting, Quick Connect, Male ...................................................103-5409

Washer, Rubber, 3/8" ID x 0.562 OD .......................................... 05-5723

Screws:

Button Head Socket, #6-32 x 1/2" ..................................................101-9805

Button Head Socket, #6-32 x 3/8" ..................................................101-9803

Pan Head #2-56 x 1/4" ..................................................................... 01-6408

Sensor, Combustibles ........................................................................ 55-0040

Washers:

Lock, Internal Tooth, #6 ...............................................................102-5167

Rubber, 3/8" ID x 0.562 OD............................................................. 05-5723

Wave, Sensor Hold Down .............................................................102-4663

Instruction 55-9002 33

Gas Pup

Accessories

Barhole Probe Assemblies:

30" polycarbonate probe ............................................................... 55-3001

30" aluminum probe ..................................................................3474-1210

Cap, Vinyl Tip (for polycarbonage probe tube) ........................... 05-4751

Calibration Kits:

Includes on-demand regulator, 3 feet of ¼" tubing, and

a quick-connect female fitting...................................................... 55-8002

On-demand regulator only........................................................... 55-0064

Calibration Gas:

- Zero Air, 20.9% O2 in air, 103 L Tank....................................... 51-7131

- 2.5 ±0.03% Methane in air, 103 L Tank .................................... 51-1121

- 100 ±2% Methane, 58 L Tank .................................................... 55-0060

Carrying Cases:

Hard Plastic Carrying Case: Provides storage space for the

instrument, gas probe and hose, and other miscellaneous

accessories..................................................................................... 55-0039

Soft Carrying Case: Holds the instrument and gas probe,

supplied with a shoulder strap .................................................... 55-0044

Check Gas: 500 ppm Methane, 103 L Tank .................................... 51-1816

Filters (fits inside filter chamber of gas probe):

Foam Filter Element (package of 10): Protects against

dust and dirt from entering the instrument’s gas tubing. ......5500-7100

Charcoal Filter Pack (package of 10): Provides the ability
to detect the difference between petroleum vapors and

natural gas. ................................................................................5500-7400

Pressure Hose Kit: Includes a 48" coiled polyurethane tube

with a quick-connect female fitting on one end and a quick­connect insert plug on the other. Also includes a 1/8-NPT
quick-connect socket. Use this kit to check regulator

pressure and gas pressure in piping............................................ 55-0038

Service Line Pressure Testing Kit: Includes two 2-foot

sections of ¼" tubing, tee with pressure value,
quick-connect male fittings on each end of tubing,
plus an 1/8-NPT quick-connect socket. Use this kit to
pressure prove new and repaired piping where the piping

is pressurized with air and then monitored for leakage. ........... 55-0072

Socket, Quick-Connect, 1/4-NPT (use on 55-0038 & 55-0072)......103-5386

Socket, Quick-Connect, 1/8-NPT (part of 55-0038 & 55-0072) ....103-5396

Tubing Coupler: Provides the ability to couple together two

sections of tubing that have quick-connect female fittings........ 55-0046

Water Trap Assembly...................................................................... 55-0063

Particulate Filter (package of 3)................................................ 07-1644

Parts & Service

Gas Pup

34 Instruction 55-9002

Service Centers

Service and replacement parts can be obtained by contacting a Bacharach
Service Center at the following locations:

Parts & Service

United States
California

7281 Garden Grove Blvd.,
Suite H
Garden Grove, CA 92841
Phone: [phone]
Fax: [phone]
Email: [e-mail]

Indiana

8618 Louisiana Place
Merrillville, IN 46410
Phone: [phone]
Fax: [phone]
Email: [e-mail]

New Jersey

7300 Industrial Park
Rte. 130, Bldg. 22
Pennsauken, NJ 08110
Phone: [phone]
Fax: [phone]
Email: [e-mail]

Pennsylvania

621 Hunt Valley Circle
New Kensington, PA 15068
Phone: [phone]
Fax: [phone]
Email: [e-mail]

Texas

5151 Mitchelldale, B-4
Houston, TX 77092
Phone: [phone]
Fax: [phone]
Email: [e-mail]

Canada

Bacharach of Canada, Inc.
250 Shields Court Unit #3
Markham, Ontario L3R 9W7
Canada
Phone: [phone]
Fax: [phone]
Email: [e-mail]

México

Bacharach de México
Playa Regatas No. 473 Tercer Piso
Col. Militar Marte
Delegación Iztacalco, 08830
México D.F. México
Phones: [phone]

[phone]
FAX: [phone]
Email: bacharach@prodigy .net.mx

Europe
European Headquarters

Bacharach Instruments
Sovereign House, Queensway
Royal Leamington Spa
Warwickshire CV31 3JR
United Kingdom
Phone: [phone]
Fax: [phone]

Sales / Service - Denmark

Bacharach Instruments Int’l
P.O. Box 44
39 Lindegade
DK 6070 Christiansfeld

Denmark
Phone: [phone]
Fax: [phone]
Email: [e-mail]

Instruction 55-9002 35

Gas Pup

World Headquarters

621 Hunt Valley Circle, New Kensington, PA 15068-7974

Ph: 724-334-5000 • Fax: [phone] • Toll Free: 800-736-4666

Website: www.bacharach-inc.com • E-mail: [e-mail]

Printed in U.S.A.