Bacharach HGM-SZ Guide

Single Zone Gas Monitors
HGM-SZ (Halogen) and AGM-SZ (Ammonia)
Instruction 3015-4256
Installation / Operation / Maintenance
Rev 13 – January 2013
Patent 6,590,690
UL 61010-1
CSA 22.2 No. 61010-1
EN 14624
Product Leadership • Training • Service • Reliability

Single Zone Gas Monitor
ii P/N: 3015-4256 Rev 13
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 two (2) years 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 warranty set forth in paragraph 1 does not apply to parts the Operating Instructions designate as having a limited
shelf-life or as being expended in normal use (e.g., filters).
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 OBLIGA-
TION, 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.
Register your warranty by visiting
www.MyBacharach.com
NOTICE
Effective as of revision 4, this instruction manual refers to the current “new style” of Single-Zone leak monitoring
equipment (which has its pump mounted on the inside bottom of the cabinet). For information on the older style of
monitoring equipment (pump mounted to the inside top of the cabinet), refer to Rev 3 of this manual. Contact
Bacharach for additional information.
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.
Patent 6,590,690
Copyright © 2005-2012, Bacharach, Inc. All rights reserved.
BACHARACH®is a registered trademark of Bacharach, Inc.
All other trademarks, trade names, service marks and logos referenced herein belong to their respective owners.

Single Zone Gas Monitor
P/N: 3015-4256 Rev 13 iii
Table of Contents
SECTION 1. INTRODUCTION..................................................................................................................... 1
1.1. How to Use This Manual.....................................................................................................................1
1.2. Warning Statements...........................................................................................................................1
1.3. Caution Statements ............................................................................................................................ 1
1.4. Hazard Symbols Located on the Monitor ...........................................................................................1
1.5. Safety Precautions..............................................................................................................................1
1.5.1. AC Power Supply ....................................................................................................................2
1.5.2. Protective Grounding...............................................................................................................2
1.5.3. Explosive Atmosphere.............................................................................................................2
1.5.4. Proper Exhaust Venting ..........................................................................................................2
1.5.5. Accessing the Interior of the Monitor.......................................................................................2
1.5.6. Misuse and Modifications to the Monitor.................................................................................2
1.5.7. In Case of Malfunction.............................................................................................................2
1.5.8. Fusing......................................................................................................................................3
1.5.9. Installation Category................................................................................................................3
1.5.10.Altitude Limit............................................................................................................................ 3
1.5.11.Cleaning ..................................................................................................................................3
1.6. Functional Overview...........................................................................................................................3
1.6.1. General Description and Use..................................................................................................3
1.6.2. Understanding Monitoring Levels............................................................................................3
1.6.3. Suggested Location of Sampling Point ...................................................................................4
1.7. Specifications......................................................................................................................................5
SECTION 2. INSTALLATION......................................................................................................................7
2.1. Installation Considerations..................................................................................................................7
2.1.1. Warnings and Cautions...........................................................................................................7
2.1.2. Inspection................................................................................................................................7
2.1.3. Location of the Monitor............................................................................................................ 7
2.2. Mounting Instructions..........................................................................................................................7
2.3. Connecting Gas Sample and Exhaust Lines......................................................................................8
2.3.1. Overview..................................................................................................................................8
2.3.2. Tubing Considerations ............................................................................................................9
2.3.3. Connecting the Gas Sample Line............................................................................................9
2.3.4. Connecting the Exhaust Line ................................................................................................10
2.3.5. Connecting the Purge Line....................................................................................................10
2.3.6. Installing Optional Splitter Kit ................................................................................................10
2.3.7. Connecting the Water Trap...................................................................................................10
2.4. Interior Schematic (Halogen HGM) ..................................................................................................11
2.5. Interior Schematic (Ammonia AGM).................................................................................................12
2.6. Electrical Wiring................................................................................................................................13
2.7. Connecting External Alarms.............................................................................................................14
2.7.1. Overview................................................................................................................................14
2.7.2. Connection ............................................................................................................................14
2.8. 4–20 mA Current Loop Interface......................................................................................................16
SECTION 3. OPERATION.........................................................................................................................17
3.1. Front Panel Display and Controls.....................................................................................................17
3.2. General Operation ............................................................................................................................18
3.3. Display Screens................................................................................................................................19
3.3.1. Initial Power Up .....................................................................................................................19
3.3.2. Data Display Screen..............................................................................................................19
3.3.3. Function Screens ..................................................................................................................19
3.4. Gas Alarms.......................................................................................................................................22

Single Zone Gas Monitor
iv P/N: 3015-4256 Rev 13
3.4.1. Overview................................................................................................................................22
3.4.2. Clearing / Silencing a Gas Alarm ..........................................................................................22
3.4.3. Viewing the Gas Alarm Log...................................................................................................22
3.5. System Faults...................................................................................................................................23
3.5.1. Overview................................................................................................................................23
3.5.2. Clearing / Silencing a Fault Alarm.........................................................................................23
3.5.3. Viewing the Fault Log............................................................................................................23
3.5.4. Fault Codes...........................................................................................................................24
3.6. Clearing the Stored PPM Log, Alarm and Fault Data.......................................................................25
3.7. Reset to Factory Default Settings.....................................................................................................25
3.8. The P-CHK Function.........................................................................................................................25
3.8.1. Overview................................................................................................................................25
3.8.2. Keypad Functions..................................................................................................................25
3.8.3. Screen Display ......................................................................................................................25
3.9. The DIAGNOS Function...................................................................................................................26
3.9.1. Overview................................................................................................................................26
3.9.2. Keypad Functions..................................................................................................................26
3.9.3. First Diagnostic Screen .........................................................................................................26
3.9.4. Second Diagnostic Screen....................................................................................................26
3.10. The Calibration Function...................................................................................................................27
3.10.1.Overview................................................................................................................................27
3.10.2.Calibration Procedure............................................................................................................27
3.10.3.Adjusting Calibration Factor..................................................................................................27
SECTION 4. MAINTENANCE....................................................................................................................28
4.1. Warnings and Cautions ....................................................................................................................28
4.2. Charcoal Filter (Halogen Gas Monitor Only) ....................................................................................28
4.3. Hydrophobic Filters...........................................................................................................................28
4.4. Servicing Air Lines and Termination Filters......................................................................................28
4.5. Fuses................................................................................................................................................29
4.6. Sample Pump ...................................................................................................................................29
4.7. End-of-Line Water Stop (Optional)...................................................................................................29
4.8. Water Trap (Optional).......................................................................................................................29
4.9. Clock Battery ....................................................................................................................................29
4.10. Replacement Parts and Optional Accessories.................................................................................30
4.11. Service Centers ................................................................................................................................31
APPENDIX A. DATA TABLES..................................................................................................................32
A.1. Recommended Alarm Settings...........................................................................................................32
A.2. Response Time/Flow Rate .................................................................................................................33
APPENDIX B. AGENCY APPROVALS ....................................................................................................34

Single Zone Gas Monitor
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SECTION 1. INTRODUCTION
1.1. How to Use This Manual
Thank you for investing in a BACHARACH Single Zone Monitor. This manual provides important
information on how to install, operate, and service the SZ monitoring unit.
To assure operator safety and the proper use of the monitor, please read, understand, and follow the
contents of this manual.
If you have a working knowledge of gas monitors, you will find this manual useful as a reference tool. If
you are new to the use of gas monitors, you can educate yourself about the principles of gas detection
and the proper operation of this device by reading this manual thoroughly.
1.2. Warning Statements
The use of the word WARNING in this manual denotes a potential hazard associated with the use of this
equipment. It calls attention to a procedure, practice, or condition, or the like, which if not correctly
performed or adhered to, could result in personal injury or death.
1.3. Caution Statements
The use of the word CAUTION in this manual denotes a potential hazard associated with the use of this
equipment. It calls attention to a procedure, practice, condition, or the like, which if not correctly
performed or adhered to, could result in damage to the equipment.
1.4. Hazard Symbols Located on the Monitor
This symbol indicates the need to consult this manual when opening the enclosure.
WARNING: A potential risk exists if the operating instructions are not followed.
This symbol indicates the presence of electric shock hazards when enclosure is opened.
WARNING: To avoid risk of injury from electric shock, do not open the enclosure without
first disconnecting AC power.
1.5. Safety Precautions
WARNING: This instrument has not been designed to be intrinsically safe for use in areas
classified as hazardous locations. For your safety, DO NOT use it in hazardous (classified)
locations.
WARNING: This is NOT a safety device. Some gases which this instrument can detect
may be combustible/flammable. When properly configured, this instrument is designed to
alarm at concentrations that are lower than the explosive limit of the gas. As such, it is the
buyer’s responsibility to initiate an immediate planned response to any gas leaks as soon
as they are detected. This equipment should NEVER be used to measure or sample
gases at or above their respective lower explosive limits.
WARNING: The Single Zone gas monitor is not to be used in any application that is
beyond its intended purpose or beyond the scope of its specifications. Failure to follow
this warning can result in personal injury or damage to the equipment. For details on
appropriate use, refer to the general description, application, and operation discussions in
this manual.

Single Zone Gas Monitor
2 P/N: 3015-4256 Rev 13
1.5.1. AC Power Supply
IMPORTANT: The Single Zone monitor uses a universal power supply that is capable of
accepting inputs of 100 to 240 VAC, 50/60 Hz. The monitor’s power consumption is
15 Watts. It is highly recommended that the monitor be connected directly to the AC power
source, preferably on its own circuit (with UPS or surge protection).
WARNING: A switch or circuit breaker rated 1.0 A, 250 VAC, with a minimum terminal
spacing of 3.0 mm must be attached to the monitor’s AC power leads. This switch must
also be located in close proximity to the monitor, and be in easy reach of the operator. This
switch should also be clearly marked as the monitor’s main AC disconnect device.
1.5.2. Protective Grounding
WARNING: Under no circumstances should the SZ unit be operated without connection to
a protective ground. Doing so poses a potential shock hazard and is also a violation of
electrical safety standards applicable to this type of equipment.
1.5.3. Explosive Atmosphere
WARNING: Do not operate this equipment in the presence of flammable liquids, vapors or
aerosols. Operation of any electrical equipment in such an environment constitutes a
safety hazard.
1.5.4. Proper Exhaust Venting
WARNING: It is imperative that the monitor’s exhaust port be vented as described in this
manual. Failure to do so may constitute a safety hazard.
1.5.5. Accessing the Interior of the Monitor
WARNING: Extreme care should be exercised when accessing the interior of the monitor.
Only qualified electrical maintenance personnel should perform connections and
adjustments. Always remove AC power before performing work inside the monitor.
1.5.6. Misuse and Modifications to the Monitor
WARNING: The protection provided by the monitor may be impaired if the monitor is used
in a manner not specified by Bacharach, Inc. Modifications to this monitor, not expressly
approved, will void the warranty.
NOTE: Use ONLY the provided knockouts for electrical and communications wiring.
Drilling into the box will void the warranty.
1.5.7. In Case of Malfunction
WARNING: Do not continue to use this equipment if there are any symptoms of
malfunction or failure. In the case of such occurrence, de-energize the power supply and
contact a qualified repair technician or the nearest Bacharach Service Center.

Single Zone Gas Monitor
P/N: 3015-4256 Rev 13 3
1.5.8. Fusing
WARNING: This device uses type “F” fuses (F1 and F2) rated at 1.0 A, 250 VAC.
Replace ONLY with Bacharach-approved fuses.
1.5.9. Installation Category
IMPORTANT: This device is classified as Installation Category II, Pollution Degree II, as
defined by UL.
1.5.10. Altitude Limit
IMPORTANT: This device is designed for operation at or below an altitude of 6,562 ft
(2,000 m). Do not operate this device above this altitude limit.
1.5.11. Cleaning
NOTE: To clean the outside of the case use a dry cloth. To avoid shock hazard and/or
equipment damage, DO NOT use soap and water.
1.6. Functional Overview
1.6.1. General Description and Use
Single zone gas monitors are specified to support compliance to federal, state and local safety codes
governing gas emissions. Avoiding significant loss reduces equipment replacement costs, maintains
equipment efficiency, promotes safety, and protects the environment.
The Bacharach SZ is designed to continuously test for the presence of gas in an area that is located up to
500 ft (152.4 m) away from the monitor. The SZ monitor displays the type of gas being monitored, along
with displaying both the current gas level and the peak gas level detected in that area on its front panel
LCD. The monitor retains a log of previous readings that can be easily accessed for analysis.
An audible alarm and front panel indicators are provided to signal alarm and fault conditions, and relay
contacts are provided that can be used to trigger external alarm devices in the event of a system fault, or
if a leak (small), spill (medium), or evacuation (large) level of gas is detected. The system also includes a
4−20 mA current loop interface that can be connected to remote monitoring equipment.
The SZ requires only minor periodic maintenance such as the occasional replacement of filters. The
monitor incorporates active diagnostics that continuously check the system for proper operation. A front
panel indicator is provided to alert an operator of system malfunctions, and fault codes are generated that
enable the operator to identify the cause of the fault.
1.6.2. Understanding Monitoring Levels
Effective use of this monitor requires an understanding of what constitutes reasonable alarm set points for
the type of gas being monitored. Most systems leak some gas. In a good “tight” installation these
background levels will be acceptably low and often do not require corrective action. You can reduce
nuisance alarms and needless service calls if the alarm levels are set at practical limits. Bacharach has
developed recommended monitoring levels based on compliance to ANSI/BSR ASHRAE 15-2007 and
ASHRAE Safety Code 34-2007. These reference levels are listed in the Appendix.

Single Zone Gas Monitor
4 P/N: 3015-4256 Rev 13
The SZ monitor is shipped with its leak, spill, and evacuate alarm levels set at 100, 300 and 500 ppm
respectively. Setting the monitor at these recommended alarm levels will satisfy the needs of most users.
However, the ppm levels generated by system leaks into the environment are greatly influenced by the
volume of air in the sampling area, air circulation, size of the leak, distance to the monitoring point, and a
host of other variables. In some cases the alarm set points may need to be adjusted either up or down to
achieve effective monitoring.
1.6.3. Suggested Location of Sampling Point
At the point of a gas leak, the gas is nearly pure. As gas is dispersed into the air, the gas molecules
diffuse, causing a dilution of the original concentration. The SZ monitor measures the gas concentration
at the point the sample is collected. Therefore, if the termination of the collection line is not at the exact
point of the gas leak, then the monitor will read a diluted mixture of gas and air.
It should be noted that when refrigerant and ammonia gases are cold, they are heaver than air and settle
below the leak point. When the gas warms to room temperature, it becomes lighter than air and tends to
collect above the leak point. Consequently, the sampling point should be located as close as possible to
the source of a potential leak. If this is impractical, then the alarm set points should be adjusted to
compensate for the dilution of the gas.
The SZ monitor should be mounted outside of the mechanical room or just inside a doorway to the room.
This is the “split architecture design” for safety of the operator. The monitor should be readily accessible
for easy visual monitoring and servicing. The total length of the sample line + exhaust line can be up to
500 ft (152.4 m). If the area around the monitor is not well ventilated, then an optional exhaust line and
purge line can be run to an outside location. The total length of the exhaust line + the purge line cannot
exceed 200 ft (61.0 m).
It may be necessary to perform a “smoke” test of the mechanical room to determine the best monitoring
point. The smoke test would provide the pattern of air currents present in the room.
The SZ monitor should be kept dry. When used in a wet or humid area, it is highly recommended to use
the optional water stop accessory to avoid internal damage.
Figure 1-1. Aerial View of Example Single Zone Leak Monitor Placement in a Mechanical Room

Single Zone Gas Monitor
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1.7. Specifications
Category HGM-SZ Specifications
Product Type
Single-zone infrared monitoring system for low level continuous monitoring of CFC, HCFC
and HFC refrigerant gasses used in most commercial refrigeration systems. System design
supports compliance to the refrigerant monitoring requirements of ANSI/BSR ASHRAE 15-
2007 and ASHRAE Safety Code 34-2007.
Gas Library:
CFC HFP, R-11, R-113, R-114, R-12, R-502
HFC R-125, R-134a, R-236FA, R-245Fa, R-404a (HP62), R-407a, R-407c (AC9000), R-410a
(AZ20), R-422a, R-422d, R-427a, R-507 (AZ50), R-508b (SUVA95)
HCFC R-123, R-124, R-21, R-22, R-227, R-23, R-401a (MP39), R-402a (HP80), R-402b (HP81),
R-408a, R-409a, R-500, R-503
HALON H1211, H1301, H2402
Other FA188, FC72, HFO1234YF, N1230, R-420a, R-424a, R-426a, R-427a, R-438a
Sensitivity All gasses 1 ppm
Measuring
Range All gasses 0 to 10,000 ppm
Accuracy ±1 ppm ±10% of reading from 0-1000 ppm
(R11, R22, R113: ±10 ppm ±15% of reading 0-1000 ppm)
Response Time 105 seconds maximum (dependent on sample line length)
Category AGM-SZ Specifications
Product Type Single zone infrared monitoring system for low level continuous monitoring of ammonia
refrigerant gas used in most commercial refrigeration systems.
Gas Library Ammonia / NH3/ R-717
Sensitivity 20 PPM (minimum detection limit)
Measuring Range 25-10,000 PPM
Accuracy ±10 ppm ±10% of reading from 25 to 1,000 ppm
Response Time 180 seconds maximum (dependent on sample line length)

Single Zone Gas Monitor
6 P/N: 3015-4256 Rev 13
Category General Single Zone Specifications
Coverage Single zone
Detector Type Infrared, Non-Dispersive
Warm-up Time 15 minutes
Front Panel
3 Indicator lights:
•Green Monitor is powered on. LED glows during normal operation; flashes
when unit is in warm-up mode
•Red Alarm. LED flashes when any point has exceeded the alarm setting.
•Yellow Fault. LED flashes when there is a system fault
Size (HxWxD) 7.5" x 13.5" x 3.625" (190.5 mm x 343 mm x 92 mm)
Weight 5.5 lbs (2.5 kg)
Temperature Drift Less than 1 ppm per °C between purge cycles
Sampling Mode Automatic (continuous)
Re-Zero Automatic (approximately every 5 minutes)
System Noise Less than 50 dB(A) @ 10 feet (3m)
Monitoring Distance 500 ft. (152 m) maximum
Conditioned Signal 4-20 mA DC non-isolated output (ppm)
Alarms Four SPDT alarm contacts are provided rated 2A at 250 VAC (inductive), 5 A at
250 VAC (resistive)
Three assigned to PPM level alarms, one assigned to system faults
Power Safety Mode Fully automatic system reset. All programmed parameters retained.
Operating Temp 32 to 122 °F (0 to 50 °C)
Ambient Humidity 5% to 90% RH (non-condensing)
AC Power 100 to 240 VAC, 50/60 Hz, 15 Watts
Certification UL 61010-1, CAN/CSA 22.2 No. 61010-1 and CE Mark
Warranty 2 years from date of shipment
Altitude Limit 6,562 ft (2,000 m) maximum
Sensor Life 7-10 years