AER Esteem 399 Instruction manual

GF-135 Esteem 399 Low NOx Boiler
Installation, Operation & Maintenance Manual
Page 1of 188 AERCO International, Inc. •100 Oritani Dr. •Blauvelt, NY 10913 OMM-0089_0B
02/05/2019
USER MANUAL
Installation, Operation and Maintenance
GAS FIRED BOILER
Natural Gas or Propane Gas
Modulating & Condensing Hot
Water Boiler:
02/05/2019

GF-135 Esteem 399 Low NOx Boiler
Installation, Operation & Maintenance Manual
Page 2of 188 AERCO International, Inc. •100 Oritani Dr. •Blauvelt, NY 10913 OMM-0089_0B
02/05/2019
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]
AERCO Document Conventions
In this document, some types of information are presented as shown in the following examples:
Message Type Example and Description
NOTES
NOTE
NOTE messages indicate specific information related to the
surrounding contextual information, and highlighted for special
attention.
CAUTIONS
CAUTION!
CAUTION messages inform of potential problems relating to
the functioning of equipment, safety to persons, harm to the
environment, and/or damage to property or equipment.
WARNINGS
WARNING!
WARNING messages warn of potential dangerous situations
that may result in serious injury and/or death to persons or
animals. Text is red within a red box.
INSTRUCTIONS
How Instructions are Presented
1. Instructions are shown in a blue box with an underlined title.
2. All text, excepting in accompanying illustrations, is colored
blue.
3. All procedures are listed in steps starting with “1.”, and using
letters [a), b), c), etc.] to indicate sub-steps.
4. Steps that are continued on the next page have a “(Cont.)”
appended to the instruction title.

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Installation, Operation & Maintenance Manual
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TABLE OF CONTENTS
CHAPTER 1: SAFETY PRECAUTIONS..................................................................................................9
1.1 WARNINGS & CAUTIONS .....................................................................................................................................9
1.2 EMERGENCY SHUTDOWN..................................................................................................................................11
1.3 PROLONGED SHUTDOWN..................................................................................................................................11
CHAPTER 2: INSTALLATION...............................................................................................................15
2.1 CODE COMPLIANCE ...........................................................................................................................................15
2.2 DETERMINING PRODUCT LOCATION .................................................................................................................15
2.3 BOILER REPLACEMENT.......................................................................................................................................16
2.4 RECOMMENDED CLEARANCES ..........................................................................................................................16
2.5 RESIDENTIAL GARAGE INSTALLATIONS..............................................................................................................17
2.6 BOILER FREEZE PROTECTION FEATURE..............................................................................................................17
CHAPTER 3: COMBUSTION AIR AND VENTING................................................................................19
3.1 COMBUSTION AIR CONTAMINATION ................................................................................................................19
3.2 POTENTIAL CONTAMINATING PRODUCTS.........................................................................................................19
3.2.1 Areas Likely to Contain Contaminating Products .......................................................................................20
3.3 VENTILATION AND COMBUSTION AIR REQUIREMENTS - DIRECT VENT ............................................................20
3.4 VENTILATION AND COMBUSTION AIR REQUIREMENTS - CATEGORY IV ...........................................................21
3.5 METHODS OF SUPPLYING COMBUSTION AIR TO A CONFINED SPACE - CATEGORY IV......................................21
3.5.1 INDOOR COMBUSTION AIR.........................................................................................................................22
3.5.2 OUTDOOR COMBUSTION AIR .....................................................................................................................23
3.5.2.1 Option 1: One Permanent Opening to Outside ...................................................................................23
3.5.2.2 Option 2: Two Permanent Openings to Outside..................................................................................24
3.6 COMBINATION OF INDOOR AND OUTDOOR COMBUSTION AIR .......................................................................25
3.6.1 Outdoor Opening(s) Location .....................................................................................................................25
3.6.2 Outdoor Opening(s) Size.............................................................................................................................25
3.7 COMBUSTION AIR AND VENT PIPING ................................................................................................................25
3.8 REMOVAL OF AN EXISTING BOILER FROM A COMMON VENT SYSTEM..............................................................26
CHAPTER 4: UNIT PREPARATION......................................................................................................29
4.1 HANDLING INSTRUCTIONS.................................................................................................................................29
4.2 WALL MOUNTING INSTALLATION......................................................................................................................29
4.3 WALL MOUNTING GUIDELINES..........................................................................................................................29
4.4 STUD WALL INSTALLATION ................................................................................................................................30
4.5 BOILER MOUNTING............................................................................................................................................30
CHAPTER 5: BOILER PIPING...............................................................................................................31
5.1 GENERAL PIPING REQUIREMENTS .....................................................................................................................31
5.2 PRESSURE RELIEF VALVE ....................................................................................................................................31
5.3 BOILER AIR VENT................................................................................................................................................32
5.4 LOW WATER CUTOFF DEVICE ............................................................................................................................32
5.5 ADDITIONAL LIMIT CONTROL ............................................................................................................................33
5.6 BACKFLOW PREVENTER .....................................................................................................................................33
5.7 BOILER SYSTEM PIPING APPLICATIONS .............................................................................................................33
5.8 EXPANSION TANK AND MAKEUP WATER ..........................................................................................................33
5.8.1 Diaphragm Expansion Tank ........................................................................................................................34
5.8.2 Closed-Type Expansion Tank ......................................................................................................................34
5.9 CIRCULATOR ......................................................................................................................................................34
5.10 SIZING PRIMARY PIPING ..................................................................................................................................34
5.11 DOMESTIC HOT WATER SYSTEM PIPING ........................................................................................................34
5.12 SYSTEM PIPING - ZONE CIRCULATORS.............................................................................................................34

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5.13 SYSTEM PIPING - ZONE VALVES .......................................................................................................................35
5.14 SYSTEM PIPING - THROUGH BOILER ................................................................................................................35
5.15 SYSTEM PIPING - RADIANT HEATING ...............................................................................................................35
5.16 SYSTEM PIPING—SPECIAL APPLICATIONS .......................................................................................................36
5.17 SYSTEM PIPING—MULTIPLE UNITS INSTALLATION .........................................................................................36
CHAPTER 6: INSTALLING VENT, AIR INTAKES, AND DRAIN..........................................................43
6.1 INSTALLING VENT AND COMBUSTION AIR INTAKE............................................................................................43
6.2 INSTALLING CONDENSATE DRAIN ASSEMBLY....................................................................................................43
CHAPTER 7: GAS PIPING.....................................................................................................................45
7.1 GAS SUPPLY PIPING CONNECTION ....................................................................................................................45
7.2 NATURAL GAS ....................................................................................................................................................46
7.2.1 Pipe Sizing - Natural Gas .............................................................................................................................46
7.2.2 Natural Gas Supply Pressure Requirements ...............................................................................................47
7.3 PROPANE GAS....................................................................................................................................................47
7.3.1 Pipe Sizing – Propane Gas...........................................................................................................................47
7.3.2 Propane Gas Supply Pressure Requirements .............................................................................................48
CHAPTER 8: INTERNAL WIRING.........................................................................................................51
8.1 GENERAL REQUIREMENTS .................................................................................................................................51
8.2 FUSE LOCATIONS ...............................................................................................................................................51
8.2.1 EZ-SETUP Controller Module Fuses Location..............................................................................................51
8.2.2 Line Voltage Fuses Location........................................................................................................................52
CHAPTER 9: EXTERNAL WIRING........................................................................................................55
9.1 INSTALLATION COMPLIANCE .............................................................................................................................55
9.2 LINE VOLTAGE CONNECTIONS ...........................................................................................................................55
9.3 CIRCULATOR WIRING.........................................................................................................................................56
9.4 ALARM WIRING..................................................................................................................................................57
9.5 LOW VOLTAGE CONNECTIONS ..........................................................................................................................57
9.6 THERMOSTAT WIRING .......................................................................................................................................57
9.7 OUTDOOR SENSOR WIRING...............................................................................................................................58
9.8 DOMESTIC HOT WATER WIRING .......................................................................................................................58
9.9 ADDITIONAL BOILER LIMITS...............................................................................................................................58
9.10 EXTERNAL MODULATION CONTROL ................................................................................................................58
9.11 SYSTEM SENSOR WIRING.................................................................................................................................58
9.12 CASCADE WIRING ............................................................................................................................................59
9.13 MODBUS WIRING ............................................................................................................................................59
CHAPTER 10: BASIC EZ-SET CONTROLLER OPERATION..............................................................65
10.1 EZ-SET CONTROLLER INTRODUCTION..............................................................................................................65
10.2 EZ-SET CONTROLLER FEATURES AND FUNCTIONS...........................................................................................65
10.3 CONTROLLER NAVIGATION..............................................................................................................................66
10.4 HOME SCREEN .................................................................................................................................................68
10.5 MAIN MENU ....................................................................................................................................................70
10.6 EZ SETUP ...................................................................................................................................................71
10.7 HEATING EZ SETUP ...............................................................................................................................71
10.7.1 Select CH Demand (Default: Switch & Outdoor Reset) ............................................................................71
10.7.2 CH1 Setpoint (Default: 180°F [82°C])........................................................................................................72
10.7.3 CH2 Setpoint (Default: 140°F [60°C])........................................................................................................72
10.7.4 Select CH1 Reset Curve (Default: Finned Tube Baseboard)......................................................................72

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10.7.5 Select CH2 Reset Curve (Default: Low Mass Radiant) ..............................................................................72
10.7.6 Set Warm Weather Shutdown Temperature (Default: OFF) ....................................................................73
10.8 DOMESTIC HOT WATER EZ SETUP .......................................................................................................74
10.8.1 Select DHW Demand (Default: Switch).....................................................................................................74
10.8.2 Boiler DHW Setpoint (Default: 186°F [86°C])............................................................................................74
10.8.3 DHW Storage Setpoint (Default: 140°F [60°C]).........................................................................................75
10.8.4 DHW Priority Timeout (Default: Off) ........................................................................................................75
10.9 EZ SETUP RESET ....................................................................................................................................76
10.10 DISPLAY EZ SETUP .............................................................................................................................76
10.11 CH/DHW OPERATION ........................................................................................................................77
10.12 BOILER INFORMATION .............................................................................................................................77
10.12.1 Boiler Information Logging .....................................................................................................................79
10.13 LOCKOUT HISTORY.........................................................................................................................................80
10.13.1 Lockout Details .......................................................................................................................................80
CHAPTER 11: START-UP PREPARATION..........................................................................................85
11.1 CHECK BOILER SYSTEM WATER CHEMISTRY....................................................................................................85
11.1.1 Water pH Level 6.0 to 8.0 .........................................................................................................................85
11.1.2 Water Hardness Less Than 7 Grains .........................................................................................................85
11.1.3 Chlorinated Water ....................................................................................................................................85
11.1.4 Flush Boiler to Remove Sediment.............................................................................................................85
11.1.5 Check and Test Antifreeze ........................................................................................................................86
11.1.6 Use of Antifreeze in the Boiler System .....................................................................................................86
11.2 BOILER CLEANING ............................................................................................................................................86
11.2.1 Cleaning an Old Boiler and System ...........................................................................................................86
11.2.2 Cleaning of New Boiler/System: ...............................................................................................................87
11.2.3 Filling the Boiler System ...........................................................................................................................87
11.3 CHECK LOW WATER CUT-OFF DEVICE .............................................................................................................87
11.4 CHECK FOR GAS LEAKS.....................................................................................................................................88
11.5 CHECK THERMOSTAT CIRCUIT .........................................................................................................................88
11.6 INSPECTION OF CONDENSATE DRAIN ASSEMBLY............................................................................................89
CHAPTER 12: START-UP PROCEDURES...........................................................................................91
12.1 FINAL CHECKS BEFORE START-UP ....................................................................................................................91
12.2 ESTEEM START-UP ...........................................................................................................................................91
12.3 OPERATING INSTRUCTIONS (READ BEFORE OPERATING BOILER)..................................................................91
12.3.1 Troubleshooting Start-Up Problems.........................................................................................................93
12.4 INSPECTION OF THE ESTEEM BOILER AND SYSTEM.........................................................................................93
12.4.1 Boiler Piping inspection ............................................................................................................................93
12.4.2 Vent Piping and Combustion Air Piping inspection ..................................................................................93
12.4.3 Gas Piping Inspection................................................................................................................................94
12.4.4 Flame Pattern and Combustion Verification ............................................................................................94
12.4.5 Measure and Verify Input Rating - Natural Gas Only ...............................................................................96

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12.4.6 High Temperature Limit Testing ...............................................................................................................97
CHAPTER 13: OUTDOOR RESET CONTROL.....................................................................................99
13.1 OUTDOOR TEMPERATURE SENSOR INSTALLATION.......................................................................................100
13.2 OUTDOOR TEMPERATURE SENSOR WIRING .................................................................................................101
CHAPTER 14: EXTERNAL MODULATING CONTROL......................................................................103
14.1 WIRING THE EXTERNAL MODULATING CONTROLLER ...................................................................................103
14.2 EZ-SETUP CONTROLLER PROGRAMMING FOR EXTERNAL 0-10V SIGNAL......................................................103
14.3 EXTERNAL PROGRAMMING OF 0-10V MODULATING CONTROL...................................................................103
CHAPTER 15: CHECK-OUT PROCEDURES .....................................................................................105
CHAPTER 16: MAINTENANCE SCHEDULE......................................................................................107
16.1 SERVICE TECHNICIAN MAINTENANCE ...........................................................................................................107
16.1.1 General Maintenance .............................................................................................................................107
16.1.2 Poor Performance Maintenance ............................................................................................................107
16.1.3 Owner Maintenance ...............................................................................................................................107
CHAPTER 17: MAINTENANCE PROCEDURES ................................................................................109
17.1 REPORTED PROBLEMS ...................................................................................................................................109
17.2 SURROUNDING AREA INSPECTION ................................................................................................................109
17.3 BURNER AREA INSPECTION ...........................................................................................................................109
17.4 SYSTEM PIPING INSPECTION..........................................................................................................................110
17.5 CLEAN CONDENSATE DRAIN ASSEMBLY........................................................................................................110
17.6 VENTILATION AIR OPENINGS INSPECTION ....................................................................................................110
17.7 VENT AND COMBUSTION AIR PIPING INSPECTION........................................................................................110
17.8 BOILER SYSTEM INSPECTION .........................................................................................................................111
17.9 EXPANSION TANK INSPECTION......................................................................................................................111
17.10 BOILER RELIEF VALVE INSPECTION ..............................................................................................................111
17.11 IGNITION ELECTRODE INSPECTION..............................................................................................................112
17.12 IGNITION WIRING AND GROUND WIRING INSPECTION ..............................................................................112
17.13 CONTROL WIRING INSPECTION ...................................................................................................................112
17.14 CONTROL SETTINGS INSPECTION ................................................................................................................112
17.15 PERFORM START-UP AND CHECKOUT PROCEDURES ..................................................................................112
17.16 BURNER FLAME INSPECTION AND TROUBLESHOOTING .............................................................................113
17.17 FLAME SIGNAL INSPECTION.........................................................................................................................114
17.18 COMBUSTION LEVELS INSPECTION..............................................................................................................114
17.19 FLUE GAS TEMPERATURE CHECK ................................................................................................................114
17.20 HEAT EXCHANGER CLEANING......................................................................................................................115
17.21 REVIEWING MAINTENANCE REQUIREMENTS WITH OWNER ......................................................................115
17.22 Handling Previously Fired Combustion Chamber Insulation .......................................................................116
CHAPTER 18: EZ-SETUP CONTROLLER OPERATION AND SETTINGS.......................................117
18.1 ENTERING THE INSTALLER ACCESS CODE ......................................................................................................117
18.2 USING THE INSTALLER MENU ........................................................................................................................118
18.3 CH and DHW SETTINGS MENU ................................................................................................................121
18.3.1 Heating Operation (Default: Enabled) ....................................................................................................121
18.3.2 Demand Type (Default: Switch & Outdoor Reset)..................................................................................122
18.3.3 Absolute Max CH Setpoint (Default: 188°F [87°C]).................................................................................123
18.3.4 CH1 Maximum Setpoint (Default: 180°F [82°C]) ....................................................................................123
18.3.5 CH1 Minimum Setpoint (Default: 120°F [49°C]) .....................................................................................124
18.3.6 Reset Curve Coldest Day (Default: 0°F [-18°C]) ......................................................................................124

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18.3.7 Reset Curve Warmest Day (Default: 64°F [18°C])...................................................................................124
18.3.8 CH2 Circuit (Default: Enabled) ................................................................................................................125
18.3.9 CH2 Maximum Setpoint (Default: 140°F [60°C]) ....................................................................................125
18.3.10 CH2 Minimum Setpoint (Default: 80°F [27°C]) .....................................................................................125
18.3.11 Warm Weather Shutdown (Default: Off) .............................................................................................126
18.3.12 Pump Constant Circulation (Default: Disabled) ....................................................................................126
18.3.13 CH Post Pump Time (Default: 1 Minute) ..............................................................................................127
18.3.14 Freeze Protection (Default: Enabled) ...................................................................................................128
18.3.15 Frost Protection Setpoint (Default: -22°F [-30°C])................................................................................129
18.3.16 Parallel Shift Value (Default: 0°F [0°C]).................................................................................................129
18.3.17 CH Call Blocking (Default: 1 Minute) ....................................................................................................130
18.3.18 System Pump (Default: CH1/CH2) ........................................................................................................130
18.4 DHW SETTINGS MENU .......................................................................................................................135
18.4.1 DHW Operation (Default: Enabled) ........................................................................................................136
18.4.2 Demand Type (Default: Switch)..............................................................................................................137
18.4.3 Boiler DHW Setpoint (Default: 186°F [86°C])..........................................................................................137
18.4.4 DHW Storage Setpoint (Default: 140°F [60°C]).......................................................................................138
18.4.5 DHW on Differential (Default: 6°F [3°C]) ..............................................................................................138
18.4.6 DHW Storage Adder (Default: 46°F [25°C])............................................................................................139
18.4.7 DHW Post Pump Time (Default: 1 Minute)............................................................................................139
18.4.8 DHW Priority Timeout (Default: OFF) ....................................................................................................140
18.4.9 DHW Priority (Default: ENABLED).........................................................................................................140
18.4.10 DHW Call Blocking (Default: 0 Minutes) .............................................................................................141
18.4.11 DHW to CH Call Blocking (Default: 1 Minute) .....................................................................................141
18.4.12 Antilegionella Function (Default: DISABLED) ......................................................................................142
18.5 BOILER SETTINGS MENU ......................................................................................................................143
18.5.1 Lockout Temp (Default: 210°F [99°C]) ....................................................................................................143
18.5.2 Modbus Address (Default: 0=BCST)........................................................................................................144
18.6 RESET ALL SETTINGS MENU ...............................................................................................................144
18.7 CASCADE MENU AND OPERATING INFORMATION........................................................................................146
18.7.1 Cascade Installation – System Piping......................................................................................................148
18.7.2 Cascade Installation – System Sensor Installation..................................................................................148
18.7.3 Cascade Installation – Cascade Communication Cable...........................................................................149
18.7.4 Cascade Installation – Low Voltage Wiring Connections........................................................................149
18.7.5 Cascade Installation – Line Voltage Wiring Connections........................................................................150
18.8 CASCADE AUTODETECTION MENU ......................................................................................................151
18.8.1 Cascade Operation – Lockouts ...............................................................................................................151
18.9 CASCADE INFORMATION MENU.........................................................................................................158
18.9.1 System Temperature Logging .................................................................................................................158
18.9.2 Cascade Settings Menu ...................................................................................................................159
18.9.3 Stage Delay (Default: 60 Seconds) ..........................................................................................................160

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18.9.4 Minimum firing Rate (Default: 30%).......................................................................................................160
18.9.5 Boiler Enabling Algorithm.......................................................................................................................161
18.9.6 Boiler Disabling Algorithm ......................................................................................................................161
18.9.7 Maximum Firing Rate (Default: 398 MBH) .............................................................................................161
18.9.8 CH or DHW Boilers (Default: 0)...............................................................................................................162
18.9.9 Automatic Rotation (Default: Enabled) .................................................................................................163
18.9.10 CH Proportional Gain (Default: 7).........................................................................................................164
18.9.11 CH Integral Gain (Default: 245).............................................................................................................165
18.9.12 DHW Proportional Gain (Default: 7) .....................................................................................................166
18.9.13 DHW Integral Gain (Default: 245).........................................................................................................167
18.9.14 Modbus Address (Default: 0 = BcST) ....................................................................................................168
18.9.15 Modbus Interface .................................................................................................................................169
18.10 MANUAL OPERATION ..................................................................................................................................171
18.10.1 Fan Parameter ..............................................................................................................................171
18.10.2 CH CH1 Parameter ........................................................................................................................172
18.10.3 DHW Parameter ...........................................................................................................................172
18.10.4 SYS CH2 Parameter .......................................................................................................................173
APENNDIX A: PART AND DIMENSIONAL DRAWINGS.......................................................................175
APENNDIX B: CIRCULATOR PRESSURE LOSS CHARTS.................................................................183

GF-135 Esteem 399 Low NOx Boiler Chapter 1
Installation, Operation & Maintenance Manual Safety Precautions
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CHAPTER 1: SAFETY PRECAUTIONS
1.1 WARNINGS & CAUTIONS
The following general warnings and cautions must be given the same attention as specific
precautions included in these instructions. In addition to the requirements included in this
Manual, the installation MUST conform with local building codes, or, in the absence of local
codes, ANSI Z223.1 (National Fuel Gas Code Publication No. NFPA-54). Where ASME CSD-1
is required by local jurisdiction, the installation must conform to CSD-1.
Where applicable, the equipment must be installed in accordance with the current Installation
Code for Gas Burning Appliances and Equipment, CGA B149, and applicable Provincial
regulations for the class. Authorities having jurisdiction should be consulted before installations
are made.
See the last two pages of this chapter 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.
•Installation and service must be performed by a qualified
installer, service agency or the gas supplier.
WARNING!
•Do not use matches, candles, flames, or other sources of
ignition to check for gas leaks.
•Prior to installing this product read all instructions included in
this manual and all accompanying manuals/documents. Perform
all installation steps required in these manuals in the proper
order given. Failure to adhere to the guidelines within these
manuals can result in severe personal injury, death or
substantial property damage.
•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.
•High electrical voltages are used in this equipment, therefore
the cover on the unit’s power box must be installed at all times,
except during maintenance and servicing.

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WARNING!
A double-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.
CAUTION!
•Many of the soaps 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.
WARNING!
Should overheating occur or the gas supply fails to shut off, turn
OFF the manual gas control valve external to the appliance.
DO NOT add cold make up water when the boiler is hot. Thermal
shock can cause potential cracks in the heat exchanger.
WARNING!
IF YOU SMELL GAS:
•Do Not try to light any appliance
•Do Not touch any electrical switch
•Do Not use any phone or cell phone in your building.
•Immediately call your gas supplier from a different location.
•Follow the gas supplier’s instructions.
•If you cannot reach your gas supplier, call the fire department.
Please have the unit’s model number and the serial number from the rating label, on the
backside of the control panel when inquiring about service or troubleshooting.
AERCO International accepts no liability for any damage resulting from incorrect installation or
from the use of components or fittings not specified by AERCO International.

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Installation, Operation & Maintenance Manual Safety Precautions
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1.2 EMERGENCY SHUTDOWN
Turn the service switch on the Esteem 399 Low NOx control panel to “OFF”
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.
Figure 1-1: Typical Manual Gas Shutoff Valve
1.3 PROLONGED SHUTDOWN
After prolonged shutdown, it is recommended that the startup procedures and the safety device
test procedures in Chapter 12 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 from the unit.
The installer must identify the emergency shut-off device to those responsible for operation of
the boiler.
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,
NOTE
The Installer must identify and indicate the
location of the emergency shutdown
manual gas valve to operating personnel.

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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:
•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 cannot 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
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:

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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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GF-135 Esteem 399 Low NOx Boiler Chapter 2
Installation, Operation & Maintenance Manual Installation
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CHAPTER 2: INSTALLATION
2.1 CODE COMPLIANCE
This product must be installed in accordance to the following:
•All applicable local, state, national and provincial codes, ordinances, regulations and
laws.
•For installations in Massachusetts, code requires the boiler to be installed by a licensed
plumber or gas fitter, and if antifreeze is utilized, the installation of a reduced pressure
backflow preventer device is required in the boiler’s cold water fill or make up water
supply line.
•For installation in Massachusetts all direct vented appliances must comply with the
guidelines as outlined in section 1.3 of Chapter 1.
•The National Fuel Gas Code NFPA54/ ANSI Z 223.1—Latest edition.
•National Electric Code ANSI/NFPA 70.
•For installations in Canada -“Installation Code for Gas Burning Equipment” CGA/B149.1
or B149.2 Canadian Electrical Code Part 1 CSA C22.1.
•Standards for Controls and Safety Devices for Automatically Fired Boilers, ANSI/ASME
CSD-1, when required.
NOTE
The Esteem 399 Low NOx boiler gas manifold and gas controls
meet the safe lighting and other performance requirements as
specified in ANSI Z21.13 latest edition.
2.2 DETERMINING PRODUCT LOCATION
Before locating the Esteem 399 Low NOx check for convenient locations to:
•Heating system piping
•Venting
•Gas supply piping
•Electrical service
Ensure the boiler location allows the combustion air/vent piping to be routed directly through the
building and terminate properly outside with a minimum amount of length and bends.
Ensure the area chosen for the installation of the Esteem 399 is free of any combustible
materials, gasoline and other flammable liquids.
The Esteem boiler is certified for indoor conditioned space only.
WARNING!
Failure to remove or maintain the area free of combustible
materials, gasoline and other flammable liquids or vapors can
result in severe personal injury, death or substantial property
damage.
Ensure the Esteem 399 and its controls are protected from dripping or spraying water during
normal operation or service.

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The Esteem 399 Low NOx should be installed in a location so that any water leaking from the
boiler or piping connections or relief valve will not cause damage to the area surrounding the
unit or any lower floors in the structure.
2.3 BOILER REPLACEMENT
If the Esteem 399 is replacing an existing boiler, the following items should be checked and
corrected prior to installation:
•Boiler piping leaks and corrosion.
•Improper location and sizing of the expansion tank on the boiler heating loop.
•If applicable, level and quality of freeze protection within the boiler system.
•See the warning in section 17.22 Handling Previously Fired Combustion Chamber
Insulation.
2.4 RECOMMENDED CLEARANCES
The Esteem 399 Low NOx is approved for zero clearance to combustibles, excluding vent and
boiler piping.
•Boiler Piping - 1/4 inch from combustible materials.
•See Vent System Installation Supplement GF-125V for vent clearance requirements.
To provide service access to the unit it is recommended that the following clearances be
maintained:
Surface Dimension
Top Jacket 24 inches [610 mm].
Front 24 inches [610 mm].
Rear 0 inches
Sides 6 inches [153 mm]
Bottom Piping 24 inches [610 mm].
WARNING!
If the clearances listed above cannot be maintained or the
enclosure in which the boiler is installed is less than 85 cubic feet,
the space must be ventilated. See chapter 3 for requirements.
NOTE
When maintaining zero clearance or less than recommended
clearances, some product labeling may become hidden and
unreadable.

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WARNING!
When installing the Esteem boiler in a confined space, sufficient
air must be provided for proper combustion and venting and to
allow, under normal operating conditions, proper air flow around
the product to maintain ambient temperatures within safe limits to
comply with the National Fuel Gas Code NFPA 54…Latest
Edition.
2.5 RESIDENTIAL GARAGE INSTALLATIONS
When installing the Esteem boiler in a residential garage, the following special precautions
per NFPA 54/ANSI Z223.1 must be taken:
•Mount the unit a minimum 18 inches [458 mm] above the floor level of the garage.
•Ensure the burner and ignition devices / controls are no less than 18 inches [458
mm] above the floor level.
•Locate or protect the unit in a manner so it cannot be damaged by a moving vehicle.
2.6 BOILER FREEZE PROTECTION FEATURE
The boiler control has a freeze protection feature built in. This feature monitors the boiler
temperature and responds as follows when no call for heat is present:
•46ºF [8ºC] CH (1) & Auxiliary Boiler Pumps ON
•42ºF [6ºC] CH (1), Auxiliary Boiler & System Pumps ON, Burner operates at low fire
•60ºF [15ºC] Freeze protection ends. Burner & all pumps OFF after completing CH
Post Pump Time.
CAUTION!
The boiler freeze protection feature is disabled during a hard
lockout, however the space heating circulator will operate.
CAUTION!
The boiler freeze protection feature is designed to protect the
boiler. The boiler should be installed in a primary/secondary piping
arrangement if it is installed in an unheated space or exposed to
water temperatures of 46ºF or less. See “Chapter 5 Boiler Piping”
for primary/secondary piping examples. See Section 11.1.6 for
antifreeze guidelines.

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GF-135 Esteem 399 Low NOx Boiler Chapter 3
Installation, Operation & Maintenance Manual Combustion Air/Venting
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CHAPTER 3: COMBUSTION AIR AND VENTING
3.1 COMBUSTION AIR CONTAMINATION
WARNING!
If the Esteem boiler combustion air inlet is located in any area
likely to cause or contain contamination, or if products, which
would contaminate the air cannot be removed, the combustion air
must be re-piped and terminated to another location.
Contaminated combustion air will damage the unit and its burner
system, resulting in possible severe personal injury, death or
substantial property damage.
WARNING!
Do not operate the Esteem boiler if its combustion air inlet is
located near a laundry room or pool facility. These areas will
always contain hazardous contaminants.
Pool and laundry products and common household and hobby products often contain fluorine or
chlorine compounds. When these chemicals pass through the burner and vent system, they can
form strong acids. These acids can create corrosion of the heat exchanger, burner components
and vent system, causing serious damage and presenting a possible threat of flue gas spillage
or water leakage into the surrounding area.
Please read the information listed below. If contaminating chemicals are located near the area
of the combustion air inlet, the installer should pipe the combustion air inlet to an outside area
free of these chemicals per Chapter 5 of this installation manual.
3.2 POTENTIAL CONTAMINATING PRODUCTS
•Spray cans containing chloro/fluorocarbons
•Permanent Wave Solutions
•Chlorinated wax
•Chlorine—based swimming pool chemicals / cleaners
•Calcium Chloride for melting ice
•Sodium Chloride for water softening
•Refrigerant leaks
•Paint or varnish removers
•Hydrochloric acid / muriatic acid
•Cements and glues
•Antistatic fabric softeners used in clothes dryers
•Chlorine-type bleaches, detergents, and cleaning solvents found in household laundry
rooms
•Adhesives used to fasten building products and other similar products

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3.2.1 Areas Likely to Contain Contaminating Products
Areas likely to contain potential contaminants are as follows:
•Dry cleaning / laundry areas and establishments
•Beauty salons
•Metal fabrication shops
•Swimming pools and health spas
•Refrigeration Repair shops
•Photo processing plants
•Auto body shops
•Plastic manufacturing plants
•Furniture refinishing areas and establishments
•New building construction - Remodeling areas
•Garages with workshops
3.3 VENTILATION AND COMBUSTION AIR REQUIREMENTS - DIRECT
VENT
A Direct Vent appliance uses uncontaminated outdoor air (piped directly to the appliance) for
combustion.
For Direct Vent installations, involving only the Esteem boiler, in which the minimum service
clearances are maintained (see Recommended Clearances, section 2.4), no ventilation
openings are required.
For Direct Vent, zero clearance installations involving only the Esteem boiler, the space /
enclosure must have two openings for ventilation. The openings must be sized to provide 1
square inch of free area per 1,000 BTUH of boiler input. The openings must be placed 12
inches from the top of the space and 12 inches from the floor of the space.
For installations where the Esteem 399 Low NOx shares the space with air movers (exhaust
fan, clothes dryers, fireplaces, etc.) and other combustion equipment (gas or oil) the space must
be provided with adequate air openings to provide ventilation and combustion air to all the
equipment. Sizing of the ventilation / combustion air openings must comply with the National
Fuel Gas Code NFPA 54, ANSI Z223.1 for installations in the U.S. or CSA B149.1 and B149.2
for installations in Canada.