AER BENCHMARK 2500DF User manual

Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
BENCHMARK
2500DF – 3000DF
Dual Fuel Gas-Fired Boiler
USER MANUAL
Installation, Operation and Maintenance
Modulating & Condensing
Hot Water Boiler
Applicable to Serial Numbers
G-14-0304 and Above
Latest Update: 05/21/2014
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
DISCLAIMER
The information contained in this manual is subject to change without notice from AERCO
International, Inc. AERCO makes no warranty of any kind with respect to this material, including,
but not limited to, implied warranties of merchantability and fitness for a particular application.
AERCO International is not liable for errors appearing in this manual, nor for incidental or
consequential damages occurring in connection with the furnishing, performance, or use of
these materials.
AERCO Technical Support:
(Mon–Fri, 8am-5pm EST)
1 [phone]
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
TABLE OF CONTENTS
CHAPTER 1. SAFETY PRECAUTIONS ................................................................................................... 11
1.1 WARNINGS & CAUTIONS ................................................................................................................ 11
1.2 EMERGENCY SHUTDOWN ............................................................................................................. 12
1.3 PROLONGED SHUTDOWN ............................................................................................................. 12
CHAPTER 2. INSTALLATION .................................................................................................................. 15
2.1 INTRODUCTION ............................................................................................................................... 15
2.2 RECEIVING THE UNIT ..................................................................................................................... 15
2.3 UNPACKING ..................................................................................................................................... 15
2.4 SITE PREPARATION ........................................................................................................................ 16
2.4.1 Installation Clearances..................................................................................................................................................16
2.4.2 Setting the Unit..............................................................................................................................................................17
2.5 SUPPLY AND RETURN PIPING ...................................................................................................... 18
2.6 PRESSURE RELIEF VALVE INSTALLATION .................................................................................. 19
2.7 CONDENSATE DRAIN & PIPING ..................................................................................................... 19
2.8 GAS SUPPLY PIPING....................................................................................................................... 21
2.8.1 Gas Supply Specifications............................................................................................................................................22
2.8.2 Manual Gas Shutoff Valve............................................................................................................................................22
2.8.3 External Gas Supply Regulator.....................................................................................................................................22
2.8.3.1 Massachusetts Installations Only .................................................................................... 22
2.8.3.2 All Installations (Except Massachusetts) ......................................................................... 22
2.9 AC ELECTRICAL POWER WIRING ................................................................................................. 23
2.9.1 Electrical Power Requirements.....................................................................................................................................24
2.10 FIELD CONTROL WIRING ............................................................................................................. 25
2.10.1 Outdoor Air In (OUT) &Air Sensor Common (COM)..................................................................................................27
2.10.2 Combustion Air (AIR [AUX])........................................................................................................................................27
2.10.3 O2Sensor (O2+ & O2-)...............................................................................................................................................28
2.10.4 Spark Signal (FLW+ & FLW-) .....................................................................................................................................28
2.10.5 Analog In (+ & -)..........................................................................................................................................................28
2.10.6 B.M.S. (PWM) In (BMS+ & BMS-) ..............................................................................................................................28
2.10.7 Shield (SHLD & SHLD)...............................................................................................................................................28
2.10.8 Analog Outputs (+ & -)................................................................................................................................................28
2.10.9 RS485 Comm (+, GND, & -)........................................................................................................................................29
2.10.10 RS232 Comm (TxD & RxD)......................................................................................................................................29
2.10.11 VFD/Blower (0-10 & AGND)......................................................................................................................................29
2.10.12 Interlocks...................................................................................................................................................................29
2.10.12.1 Remote Interlock In (OUT & IN) .................................................................................. 29
2.10.12.2 Delayed Interlock In (OUT & IN) ................................................................................. 29
2.10.13 Fault Relay (NC, COM, & NO)..................................................................................................................................29
2.10.14 Auxiliary Relay Contacts (NC, COM, & NO).............................................................................................................30
2.11 FLUE GAS VENT INSTALLATION ................................................................................................. 30
2.12 COMBUSTION AIR ......................................................................................................................... 30
2.12.1 Combustion From Outside the Building......................................................................................................................31
2.12.2 Combustion Air from Inside the Building.....................................................................................................................31
2.13 DUCTED COMBUSTION AIR ......................................................................................................... 31
2.14 SEQUENCING VALVE INSTALLATION ......................................................................................... 31
CHAPTER 3. OPERATION ....................................................................................................................... 33
3.1 INTRODUCTION ............................................................................................................................... 33
3.2 CONTROL PANEL DESCRIPTION .................................................................................................. 33
3.3 CONTROL PANEL MENUS .............................................................................................................. 37
3.3.1 Menu Processing Procedure.........................................................................................................................................37
3.4 OPERATING MENU .......................................................................................................................... 39
3.5 SETUP MENU ................................................................................................................................... 39
3.6 CONFIGURATION MENU ................................................................................................................. 40
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3.7 TUNING MENU ................................................................................................................................. 42
3.8 COMBUSTION CAL MENU .............................................................................................................. 43
3.9 BST (Boiler Sequencing Technology) Menu ..................................................................................... 44
3.10 START SEQUENCE ........................................................................................................................ 46
3.11 START/STOP LEVELS ................................................................................................................... 50
CHAPTER 4. INITIAL START-UP ............................................................................................................. 53
4.1 INITIAL START-UP REQUIREMENTS ............................................................................................. 53
4.2 TOOLS AND INSTRUMENTATION FOR COMBUSTION CALIBRATION ....................................... 53
4.2.1 Required Tools & Instrumentation.................................................................................................................................53
4.2.2 Installing Gas Supply Manometer.................................................................................................................................54
4.2.3 Accessing the Analyzer Probe Port...............................................................................................................................55
4.3 NATURAL GAS COMBUSTION CALIBRATION .............................................................................. 56
4.4 PROPANE GAS COMBUSTION CALIBRATION .............................................................................. 60
4.5 REASSEMBLY .................................................................................................................................. 63
4.6 DUAL-FUEL SWITCHOVER INSTRUCTIONS ................................................................................. 64
4.6.1 Switchover from NATURAL GASto PROPANE ...........................................................................................................64
4.6.2 Switchover from PROPANE to NATURAL GAS...........................................................................................................65
4.7 OVER-TEMPERATURE LIMIT SWITCHES...................................................................................... 66
4.7.1 Digital Alarm Switch Checks and Adjustments .............................................................................................................66
CHAPTER 5. MODE OF OPERATION ..................................................................................................... 69
5.1 INTRODUCTION ............................................................................................................................... 69
5.2 INDOOR/OUTDOOR RESET MODE ................................................................................................ 69
5.2.1 Reset Ratio...................................................................................................................................................................69
5.2.2 Building Reference Temperature..................................................................................................................................69
5.2.3 Outdoor Air Temperature Sensor Installation................................................................................................................69
5.2.4 Indoor/Outdoor Startup.................................................................................................................................................69
5.3 CONSTANT SETPOINT MODE ........................................................................................................ 70
5.3.1 Setting the Setpoint.......................................................................................................................................................70
5.4 REMOTE SETPOINT MODES .......................................................................................................... 70
5.4.1 Remote Setpoint Field Wiring.......................................................................................................................................71
5.4.2 Remote Setpoint Startup...............................................................................................................................................71
5.5 DIRECT DRIVE MODES ................................................................................................................... 72
5.5.1 Direct Drive Field Wiring ...............................................................................................................................................72
5.5.2 Direct Drive Startup.......................................................................................................................................................72
5.6 AERCO CONTROL SYSTEM (ACS) ................................................................................................ 73
5.6.1 ACS External Field Wiring.............................................................................................................................................73
5.6.2 ACS Setup and Startup.................................................................................................................................................73
5.7 COMBINATION CONTROL SYSTEM (CCS).................................................................................... 73
5.7.1 Combination Control System Field Wiring....................................................................................................................74
5.7.2 Combination Control System Setup and Startup..........................................................................................................74
CHAPTER 6. SAFETY DEVICE TESTING ............................................................................................... 77
6.1 TESTING OF SAFETY DEVICES ..................................................................................................... 77
6.2 LOW GAS PRESSURE FAULT TEST .............................................................................................. 78
6.3 HIGH GAS PRESSURE TEST .......................................................................................................... 79
6.4 LOW WATER LEVEL FAULT TEST ................................................................................................. 80
6.5 WATER TEMPERATURE FAULT TEST ........................................................................................... 81
6.6 INTERLOCK TESTS ......................................................................................................................... 82
6.6.1 Remote Interlock Test...................................................................................................................................................82
6.6.2 Delayed Interlock Test..................................................................................................................................................82
6.7 FLAME FAULT TESTs ...................................................................................................................... 83
6.8 AIR FLOW FAULT TESTS ................................................................................................................ 84
6.8.1 Blower Proof Switch Test..............................................................................................................................................84
6.8.2 Blocked Inlet Switch Test..............................................................................................................................................84
6.9 SSOV PROOF OF CLOSURE SWITCH ........................................................................................... 86
6.10 PURGE SWITCH OPEN DURING PURGE .................................................................................... 87
6.11 IGNITION SWITCH OPEN DURING IGNITION .............................................................................. 87
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
6.12 SAFETY PRESSURE RELIEF VALVE TEST ................................................................................. 89
CHAPTER 7. MAINTENANCE .................................................................................................................. 91
7.1 MAINTENANCE SCHEDULE ............................................................................................................ 91
7.2 IGNITER-INJECTOR ......................................................................................................................... 91
7.3 FLAME DETECTOR .......................................................................................................................... 94
7.4 O2 SENSOR ...................................................................................................................................... 95
7.5 SAFETY DEVICE TESTING ............................................................................................................. 95
7.6 BURNER ASSEMBLY INSPECTION ................................................................................................ 96
7.7 CONDENSATE DRAIN TRAP ........................................................................................................... 99
7.8 AIR FILTER CLEANING & REPLACEMENT .................................................................................. 100
7.9 CABINET EXHAUST FAN INSPECTION & REPLACEMENT ........................................................ 101
7.10 SHUTTING THE BOILER DOWN FOR AN EXTENDED PERIOD OF TIME ............................... 102
7.11 PLACING THE BOILER BACK IN SERVICE AFTER A PROLONGED SHUTDOWN ................. 102
CHAPTER 8. TROUBLESHOOTING GUIDE .......................................................................................... 103
8.1 INTRODUCTION ............................................................................................................................. 103
8.2 ADDITIONAL FAULTS WITHOUT SPECIFIC FAULT MESSAGES ............................................... 116
CHAPTER 9. RS232 COMMUNICATION ............................................................................................... 119
9.1 INTRODUCTION ............................................................................................................................. 119
9.1.1 Acquiring the PuTTY Application................................................................................................................................119
9.1.2 Logging on to a Remote Machine Using PuTTY.........................................................................................................119
9.1.3 Running a Command on a Remote Machine Using PuTTY........................................................................................120
9.2 RS232 COMMUNICATION SETUP ................................................................................................ 121
9.3 MENU PROCESSING UTILIZING RS232 COMMUNICATION ...................................................... 121
9.4 DATA LOGGING ............................................................................................................................. 122
9.4.1 Fault Log.....................................................................................................................................................................122
9.4.2 Operation Time Log....................................................................................................................................................123
9.4.3 Sensor Log..................................................................................................................................................................124
CHAPTER 10. BOILER SEQUENCING TECHNOLOGY ....................................................................... 125
10.1 INTRODUCTION ........................................................................................................................... 125
10.2 AERCO BST Quick Start Chart ..................................................................................................... 126
10.3 BST Implementation Instruction .................................................................................................... 127
10.3.1 Option 1 - Constant Setpoint with DIRECT Wired Header Sensor..........................................................127
10.3.2 Option 2 - Constant Setpoint with MODBUS Wired Header Sensor.........................................................................128
10.3.3 Option 3 - Outdoor Reset with DIRECT WIRED Header Sensor AND DIRECT WIRED Outdoor Sensor................129
10.3.4 Option 4 - Outdoor Reset with MODBUS Header Sensor AND MODBUS Outdoor Sensor.....................................131
10.3.5 Option 5 - Remote Setpoint w/ DIRECT WIRED Header Sensor AND 4-20ma Setpoint Drive................................133
10.3.6 Option 6 - Remote Setpoint with DIRECT WIRED Header Sensor AND MODBUS Setpoint Drive..........................134
10.3.7 Option 7 - Remote Setpoint with MODBUS Header Sensor AND 4-20ma Setpoint Drive........................................135
10.3.8 Option 8 - Remote Setpoint with MODBUS Header Sensor AND MODBUS Setpoint Drive....................................137
APPENDIX A – BOILER MENU ITEM DESCRIPTIONS ...................................................................................139
APPENDIX B – STARTUP, STATUS & DISPLAY MESSAGES...........................................................................147
APPENDIX C – SENSOR RESISTANCE/VOLTAGE CHART..............................................................................151
APPENDIX D – BOILER DEFAULT SETTINGS ................................................................................................153
APPENDIX E – RECOMMENDED PERIODIC TESTING ..................................................................................155
APPENDIX F – INDOOR/OUTDOOR RESET RATIO CHARTS .........................................................................157
APPENDIX G – DIMENSIONAL DRAWING...................................................................................................161
APPENDIX G – CLEARANCE DRAWINGS .....................................................................................................162
APPENDIX I – PART LIST DRAWINGS ..........................................................................................................163
APPENDIX J – WIRING DIAGRAMS .............................................................................................................187
APPENDIX K – PIPING DRAWINGS .............................................................................................................219
APPENDIX L – C-MORE CONTROL PANEL VIEWS .......................................................................................227
APPENDIX M – RECOMMENDED SPARES...................................................................................................229
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
FORWARD
FOREWORD
The AERCO Benchmark (BMK) 2500 & 3000 MBH Dual Fuel Boilers are modulating and condensing
boilers. They are a true industry advancement that meets the needs of today's energy and environmental
concerns. Designed for application in any closed loop hydronic system, the Benchmark's modulating
capability relates energy input directly to fluctuating system loads. The turn down ratio is 15:1 maximum.
This BMK model provides extremely high efficiency and makes it ideally suited for modern low
temperature, as well as, conventional heating systems. It may be set to use either natural gas or propane
gas.
The Benchmark Model BMK 2500DF & BMK 3000DF operate within the following input and output
ranges:
Benchmark Model Input Range (BTU/hr.) Output Range (BTU/hr.)
Minimum
Maximum
Minimum
Maximum
BMK 3000DF 200,000 3,000,000 186,000 2,790,000
BMK 2500DF 167,000 2,500,000 155,000 2,325,000
The output of the boiler is a function of the unit’s firing rate (valve position) and return water temperature.
When installed and operated in accordance with this Instruction Manual, these Dual Fuel Boilers comply
with the NOx emission standards outlined in:
• South Coast Air Quality Management District (SCAQMD), Rule 1146.2
Whether used in singular or modular arrangements, the BMK 2500DF and 3000DF Dual Fuel boilers offer
the maximum venting flexibility with minimum installation space requirements. These Boilers are Category
II, III and IV, positive pressure appliances. Single and/or multiple breeched units are capable of operation
in the following vent configurations:
• Conventional, Vertical
• Conventional, Sidewall
• Conventional, Direct Vent, Vertical
• Sealed, Direct Vent, Horizontal
These boilers are capable of being vented utilizing Polypropylene and AL29-4C vent systems.
The Benchmark's advanced electronics are available in several selectable modes of operation offering
the most efficient operating methods and energy management system integration.
IMPORTANT
Unless otherwise specified, all descriptions and procedures
provided in this Installation, Operation & Maintenance Manual
apply to the Benchmark 3000 and 2500 MBH Dual Fuel boilers.
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FORWARD
Phrases, Abbreviations and Acronyms
Phrase, Abbreviation or
Acronym
Meaning
A (Amp) Ampere
ACS AERCO Control System
ADDR Address
AGND Analog Ground
ALRM Alarm
ASME American Society of Mechanical Engineers
AUX Auxiliary
BAS Building Automation System, often used interchangeably
with EMS (see
below)
Baud Rate Symbol rate, or simply the number of distinct symbol changes (signaling
events) transmitted per second. It is not equal to bits per second, unless
each symbol is 1 bit long.
BMK Benchmark series boilers
BST AERCO On-Board Boiler Management Technology
BLDG (Bldg) Building
BTU British Thermal Unit. A unit of energy approximately equal to the heat
required to raise 1 pound of water 1° F.
Cal. Calibration
CCP
Combustion Control Panel
C-More Controller
(or Control Box)
A control system developed by AERCO and currently used in all Benchmark,
Innovation and KC1000 Series product lines.
CO Carbon Monoxide
COMM (Comm) Communication
CNTL Control
DBB Double Block and Bleed. Used to define boiler gas trains containing 2 Safety
Shutoff Valves (SSOVs) and a solenoid operated vent valve. Also known as
IRI gas trains(see below)
DIP Dual In-Line Package
EMS Energy Management System; often used interchangeably with BAS
FM Factory Mutual. Used to define boiler gas trains.
GND Ground
HDR Header
HX Heat Exchanger
Hz Hertz (Cycles Per Second)
I.D. Inside Diameter
IGN Ignition
IGST Board Ignition/Stepper Board contained in C-More Control Box
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
FORWARD
Phrases, Abbreviations and Acronyms - Continued
Phrase, Abbreviation or
Acronym
Meaning
INTLK (INTL’K) Interlock
I/O Input/Output
I/O Box Input/Output (I/O) Box currently used on Benchmark, Innovation and KC1000
Series products
IP Internet Protocol
IRI Industrial Risk Insurers. A now discontinued code used to define gas trains
containing two SSOVs and a solenoid operated vent valve.
ISO Isolated
LED Light Emitting Diode
LN Low NOx
MA (mA) Milliampere (0.001 Amp), one thousandth of an amp
MAX (Max) Maximum
MIN (Min) Minimum
Modbus® A serial, half-duplex data transmission protocol developed by AEG Modicon
NC (N.C.) Normally Closed
NO (N.O.) Normally Open
NOx Nitrogen Oxide
NPT National Pipe Thread
O2 Oxygen
O.D. Outside Diameter
PMC Board A Primary Micro-Controller (PMC) board is contained in the C-More Control
Box used on all Benchmark units.
PPM Parts Per Million
PTP Point-to-Point (usually over RS232 networks)
PWM Pulse Width Modulation
REF (Ref) Reference
RES. Resistive
RS232
(or EIA-232)
A standard for serial, full-duplex (FDX) transmission of data based on the
RS232 Standard
RS422
(or EIA-422)
A standard for serial, full-duplex (FDX) transmission of data based on the
RS422 Standard
RS485
(or EIA-485)
A standard for serial, half-duplex (HDX) transmission of data based on the
RS485 Standard
RTN (Rtn) Return
SETPT (Setpt) Setpoint Temperature
SHLD (Shld) Shield
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FORWARD
Phrases, Abbreviations and Acronyms - Continued
Phrase, Abbreviation or
Acronym
Meaning
SSOV Safety Shut Off Valve
TEMP (Temp) Temperature
Terminating Resistor A resistor placed at each end of a daisy-chain or multi-drop network in order
to prevent reflections that may cause invalid data in the communication
uA Microamp (0.000001 amp), one millionth of an amp
VAC Volts, Alternating Current
VDC Volts, Direct Current
VFD Vacuum Fluorescent Display, or Variable Frequency Drive
W Watt
W.C. Water Column (W.C.)
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 1 – SAFETY PRECAUTIONS
CHAPTER 1. SAFETY PRECAUTIONS
1.1 WARNINGS & CAUTIONS
Installers and operating personnel MUST, at all times, observe all safety regulations. The following
warnings and cautions are general and must be given the same attention as specific precautions included
in these instructions. In addition to all the requirements included in this AERCO Instruction Manual, the
installation of units MUST conform with local building codes, or, in the absence of local codes, ANSI
Z223.1 (National Fuel Gas Code Publication No. NFPA-54) for gas-fired boilers and ANSI/NFPASB for LP
gas-fired boilers. Where applicable, the equipment shall be installed in accordance with the current
Installation Code for Gas Burning Appliances and Equipment, CSA B149.1, and applicable Provincial
regulations for the class; which should be carefully followed in all cases. Authorities having jurisdiction
should be consulted before installations are made.
See pages 13 and 14 for important information regarding installation of units within the Commonwealth of
Massachusetts.
IMPORTANT
This Instruction Manual is an integral part of the product and must be maintained in
legible condition. It must be given to the user by the installer and kept in a safe
place for future reference.
WARNING!
• Do not use matches, candles, flames, or other sources of ignition
to check for gas leaks.
• Fluids under pressure may cause injury to personnel or damage
to equipment when released. Be sure to shut off all incoming and
outgoing water shutoff valves. Carefully decrease all trapped
pressures to zero before performing maintenance.
• Before attempting to perform any maintenance on the unit, shut
off all gas and electrical inputs to the unit.
• The exhaust vent pipe of the unit operates under a positive
pressure and therefore must be completely sealed to prevent
leakage of combustion products into living spaces.
• Electrical voltages up to 480 VAC may be used in this
equipment. Therefore the cover on the unit’s power box (located
behind the front panel door) must be installed at all times, except
during maintenance and servicing.
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CHAPTER 1 – SAFETY PRECAUTIONS
WARNING!
• A three-pole switch must be installed on the electrical supply line
of the unit. The switch must be installed in an easily accessible
position to quickly and safely disconnect electrical service. Do
not affix switch to unit sheet metal enclosures.
• Many types of soap used for gas pipe leak testing are corrosive
to metals. The piping must be rinsed thoroughly with clean water
after leak checks have been completed.
• Do not use this boiler if any part has been under water. Call a
qualified service technician to inspect and replace any part that
has been under water.
1.2 EMERGENCY SHUTDOWN
If overheating occurs or the gas supply fails to shut off, close the manual gas shutoff valve (Figure 1-1)
located external to the unit.
NOTE
The Installer must identify and indicate the location of the
emergency shutdown manual gas valve to operating personnel.
Figure 1-1: Manual Gas Shutoff Valve
1.3 PROLONGED SHUTDOWN
After prolonged shutdown, it is recommended that the startup procedures in Chapter 4 and the safety
device test procedures in Chapter 6 of this manual be performed to verify all system-operating
parameters. If there is an emergency, turn off the electrical power supply to the AERCO boiler and close
the manual gas valve located upstream of the unit. The installer must identify the emergency shut-off
device.
MANUAL GAS SHUT-OFF VALVE
VALVE OPEN VALVE CLOSED
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 1 – SAFETY PRECAUTIONS
IMPORTANT – FOR MASSACHUSETTS INSTALLATIONS
Boiler installations within the Commonwealth of Massachusetts must conform to
the following requirements:
• Boiler must be installed by a plumber or a gas fitter who is licensed within the
Commonwealth of Massachusetts.
• Prior to unit operation, the complete gas train and all connections must be leak
tested using a non-corrosive soap.
• The vent termination must be located a minimum of 4 feet above grade level. If
side-wall venting is used, the installation must conform to the following
requirements extracted from 248 CMR 5.08 (2):
(a) For all side wall horizontally vented gas fueled equipment installed in every dwelling, building or
structure used in whole or in part for residential purposes, including those owned or operated by the
Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above
finished grade in the area of the venting, including but not limited to decks and porches, the following
requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side
wall horizontal vented gas fueled equipment, the installing plumber or gasfitter shall observe that a
hard wired carbon monoxide detector with an alarm and battery back-up is installed on the floor level
where the gas equipment is to be installed. In addition, the installing plumber or gasfitter shall
observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on
each additional level of the dwelling, building or structure served by the side wall horizontal vented
gas fueled equipment. It shall be the responsibility of the property owner to secure the services of
qualified licensed professionals for the installation of hard wired carbon monoxide detectors.
a. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl
space or an attic, the hard wired carbon monoxide detector with alarm and battery back-up may be
installed on the next adjacent floor level.
b. In the event that the requirements of this subdivision can not be met at the time of completion
of installation, the owner shall have a period of thirty (30) days to comply with the above
requirements; provided, however, that during said thirty (30) day period, a battery operated carbon
monoxide detector with an alarm shall be installed.
2. APPROVED CARBON MONOXIDE DETECTORS. Each carbon monoxide detector as required in
accordance with the above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and
IAS certified.
3. SIGNAGE. A metal or plastic identification plate shall be permanently mounted to the exterior of
the building at a minimum height of eight (8) feet above grade directly in line with the exhaust vent
terminal for the horizontally vented gas fueled heating appliance or equipment. The sign shall read, in
print size no less than one-half (1/2) inch in size, "GAS VENT DIRECTLY BELOW. KEEP CLEAR
OF ALL OBSTRUCTIONS".
4. INSPECTION. The state or local gas inspector of the side wall horizontally vented gas fueled
equipment shall not approve the installation unless, upon inspection, the inspector observes carbon
monoxide detectors and signage installed in accordance with the provisions of 248 CMR 5.08(2)(a)1
through 4.
(b) EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:
1. The equipment listed in Chapter 10 entitled "Equipment Not Required To Be Vented" in the most
current edition of NFPA 54 as adopted by the Board; and
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CHAPTER 1 – SAFETY PRECAUTIONS
2. Product Approved side wall horizontally vented gas fueled equipment installed in a room or
structure separate from the dwelling, building or structure used in whole or in part for residential
purposes.
(c) MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM PROVIDED. When
the manufacturer of Product Approved side wall horizontally vented gas equipment provides a venting
system design or venting system components with the equipment, the instructions provided by the
manufacturer for installation of the equipment and the venting system shall include:
1. Detailed instructions for the installation of the venting system design or the venting system
components; and
2. A complete parts list for the venting system design or venting system.
(d) MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED.
When the manufacturer of a Product Approved side wall horizontally vented gas fueled equipment does
not provide the parts for venting the flue gases, but identifies "special venting systems", the following
requirements shall be satisfied by the manufacturer:
1. The referenced "special venting system" instructions shall be included with the appliance or
equipment installation instructions; and
2. The "special venting systems" shall be Product Approved by the Board, and the instructions for
that system shall include a parts list and detailed installation instructions.
(e) A copy of all installation instructions for all Product Approved side wall horizontally vented gas fueled
equipment, all venting instructions, all parts lists for venting instructions, and/or all venting design
instructions shall remain with the appliance or equipment at the completion of the installation.
[End of Extracted Information From 248 CMR 5.08 (2)]
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 2 – INSTALLATION
CHAPTER 2. INSTALLATION
2.1 INTRODUCTION
This Chapter provides the descriptions and procedures necessary to unpack, inspect and install the
AERCO Benchmark Model BMK 2500 or 3000 Dual Fuel boiler.
2.2 RECEIVING THE UNIT
Each Benchmark Boiler System is shipped as a single crated unit. The shipping weight for these models
is approximately 2200 pounds. The unit must be moved with the proper rigging equipment for safety and
to avoid equipment damage. The unit should be completely inspected for evidence of shipping damage
and shipment completeness at the time of receipt from the carrier and before the bill of lading is signed.
NOTE
AERCO is not responsible for lost or damaged freight. Each unit
has a Tip-N-Tell indicator on the outside of the crate. This
indicates if the unit has been turned on its side during shipment. If
the Tip-N-Tell indicator is tripped, do not sign for the shipment.
Note the information on the carrier’s paperwork and request a
freight claim and inspection by a claims adjuster before
proceeding. Any other visual damage to the packaging materials
should also be made clear to the delivering carrier.
2.3 UNPACKING
Carefully unpack the unit taking care not to damage the unit enclosure when cutting away packaging
materials
After unpacking, a close inspection of the unit should be made to ensure that there is no evidence of
damage not indicated by the Tip-N-Tell indicator. The freight carrier should be notified immediately if any
damage is detected.
The following accessories come standard with each unit and are either packed separately within the unit’s
shipping container or are factory installed on the unit:
• Pressure/Temperature Gauge
• ASME Pressure Relief Valve
• Condensate Drain Trap (part no. 24060)
• 2” Gas Supply Shutoff Valve
When optional accessories are ordered, they may be packed within the unit’s shipping container, factory
installed on the unit, or packed and shipped in a separate container. Any standard or optional accessories
shipped loose should be identified and stored in a safe place until ready for installation or use.
Ithink I need to hire an engineer to look afterHa!
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 2 – INSTALLATION
2.4 SITE PREPARATION
Ensure that the site selected for installation of the Benchmark Boiler includes:
• Access to AC Input Power at 208-230 VAC, Three-Phase, 60 Hz @ 20 Amps
OR 460 VAC, Three-Phase, 60 Hz @ 15 Amps
• Access to NATURAL GAS line at a minimum pressure of 8” W.C. with unit in operation
(approximately 20” W.C. static) or PROPANE Gas line at a minimum pressure of 4“ W.C.
at full (100%) fire rate.
2.4.1 Installation Clearances
The Benchmark 2500 & 3000 Models are packaged in an enclosure having identical exterior dimensions.
The unit must be installed with the prescribed clearances for service as shown in Figure 2-1. The
minimum clearance dimensions, required by AERCO, are listed below. However, if Local Building Codes
require additional clearances, these codes shall supersede AERCO’s requirements. Minimum acceptable
clearances required are as follows:
• Sides: 24 inches
• Front : 24 inches
• Rear: 24 inches
• Top: 18 inches
All gas piping, water piping and electrical conduit or cable must be arranged so that they do not interfere
with the removal of any panels, or inhibit service or maintenance of the unit.
Figure 2-1: Benchmark Boiler Models 2500 & 3000 Clearances
NOTE
Ensure that
condensate
assembly is not
located over
the
housekeeping
pad.
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 2 – INSTALLATION
WARNING!
Keep the unit area clear and free from all combustible materials
and flammable vapors or liquids.
While packaged in the shipping container, the unit must be moved
by pallet jack or forklift from the FRONT ONLY.
FOR MASSACHUSSETTS ONLY:
For Massachusetts installations, the unit must be installed by a plumber or gas-
fitter licensed within the Commonwealth of Massachusetts. In addition, the
installation must comply with all requirements specified in Chapter 1 (Safety
Precautions), pages 11 and 12.
2.4.2 Setting the Unit
The unit must be installed on a 4 inch to 8 inch concrete housekeeping pad to ensure proper condensate
drainage. Ensure that the condensate assembly at the rear of the unit is not positioned above the
housekeeping pad during installation so as not to interference with condensate piping.
If anchoring the unit, refer to Figure 2-1b for anchor locations.
NOTES:
1) All holes are flush with the bottom surface of the frame
2) All dimensions shown are in inches [millimeters]
Figure 2-1b: BMK2500 & BMK3000 Anchor Bolt Locations
A total of 3 lifting lugs are provided at the top of the primary heat exchanger as shown in Figure 2-2. The
unit is shipped with the top cover stored inside the shipping enclosure so that the lifting lugs are exposed.
Remove the four (4) lag screws securing the unit to the shipping skid. Lift the unit off the shipping skid
and position it on the 4 inch to 8 inch concrete housekeeping pad (required) in the desired location.
WARNING!
When lifting or moving the boiler: do not attempt to manipulate the
boiler using the gas train or blower.
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 2 – INSTALLATION
Figure 2-2: Boiler Lifting Provisions
In multiple unit installations, it is important to plan the position of each unit in advance. Sufficient space for
piping connections and future service/maintenance requirements must also be taken into consideration.
All piping must include ample provisions for expansion.
2.5 SUPPLY AND RETURN PIPING
The Benchmark Boiler utilizes 4” 150# flanges for the water system supply and return piping connections.
The physical location of the supply and return piping connections are on the rear of the unit as shown in
Figure 2-3.
Figure 2-3: Supply and Return Locations
2” PROPANE INLET
LIFTING LUGS
(3 POSITIONS)
2” NATURAL GAS INLET
HOT WATER OUTLET
(SUPPLY)
EXHAUST
MANIFOLD
CONDENSATE
DRAIN
AIR INLET
PRIMARY
WATER INLET
(RETURN)
DRAIN VALVE
Page 18 of 234 AERCO International, Inc. •100 Oritani Dr. •Blauvelt, NY 10913 OMM-0099_0A
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 2 – INSTALLATION
2.6 PRESSURE RELIEF VALVE INSTALLATION
An ASME rated Pressure Relief Valve is supplied with each Benchmark Boiler. The pressure rating for the
relief valve must be specified on the sales order. Available pressure ratings range from 30 psi to 160 psi,
depending upon pressure vessel rated pressure. The relief valve is installed on the hot water outlet of the
boiler as shown in Figure 2-4. A suitable pipe joint compound should be used on the threaded
connections. Any excess should be wiped off to avoid getting any joint compound into the valve body.
The relief valve must be piped to within 12 inches of the floor to prevent injury in the event of a discharge.
are allowed in the discharge line. In multiple unit installations the discharge lines must not be manifolded
together. Each must be individually run to a suitable discharge location.
PARTIAL REAR VIEW
Figure 2-4: P&T Relief Valve Location
2.7 CONDENSATE DRAIN & PIPING
The Benchmark Boiler is designed to condense water vapor from the flue products. Therefore, the
installation must have provisions for suitable condensate drainage or collection.
The condensate drain port located on the exhaust manifold (Figure 2-5) must be connected to the
condensate trap (P/N 24060) which is packed separately within the unit’s shipping container. The
condensate trap outlet connection features a tapped 3/4” NPT drain port.
PRESSURE
RELIEF VALVE
4” BOILER HOT
WATER OUTLET
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Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
CHAPTER 2 – INSTALLATION
Figure 2-5: Condensate Drain Connection Location
A sample condensate trap installation is shown in Figure 2-6. However, the actual installation details for
the trap will vary depending on the available clearances, housekeeping pad height/ dimensions and other
prevailing conditions at the site. The following general guidelines must be observed to ensure proper
condensate drainage:
• The condensate trap inlet (Figure 2-6) must be level with, or lower than the exhaust manifold drain
port.
• The base of the condensate trap must be supported to ensure that it is level (horizontal).
• The trap must be removable for routine maintenance. AERCO recommends that a union be
utilized between the exhaust manifold condensate drain port and the trap inlet port.
While observing the above guidelines, install the condensate trap as follows:
Condensate Trap Installation
1. Connect the condensate trap inlet to the exhaust manifold drain connection using the
appropriate piping components (nipples, reducers, elbows, etc.) for the boiler installation
site.
2. At the condensate trap outlet, install a 3/4” NPT nipple.
3. Connect a length of 1” I.D polypropylene hose to the trap outlet and secure with a hose
clamp.
4. Route the hose on the trap outlet to a nearby floor drain.
If a floor drain is not available, a condensate pump can be used to remove the condensate to an
appropriate drain location. The maximum condensate flow rate is 30 GPH. The condensate drain trap,
associated fittings and drain line must be removable for routine maintenance.
WARNING!
Use PVC, stainless steel, aluminum or polypropylene for
condensate drain piping (Figure 2-6). DO NOT use carbon or
copper components.
AIR INLET
PRIMARY
WATER INLET
DRAIN VALVE
CONDENSATE DRAIN PORT
1/4” ANALYZER
NPT PORT
EXHAST
MANIFOLD
Page 20 of 234 AERCO International, Inc. •100 Oritani Dr. •Blauvelt, NY 10913 OMM-0099_0A
05/21/2014 Phone: [phone] GF-145