AER Esteem 399 Manual

Instruction
No.
AERCO INTERNATIONAL, Inc. Northvale, New Jersey, 07647 USA
Installation and Maintenance
Manual
Esteem 399
Low NOx
Gas Fired
Boiler
Visit www.aerco.com to View the Latest
Product Manuals and Information.
Printed in U.S.A. REVISED MAY 2010
GF-125
OMM-0048_0A

Telephone Support
[phone]
Direct to AERCO Technical Support
(8 to 5 pm EST, Monday through Friday)
Please have the unit’s model number
and the serial number from the rating la-
bel on the backside of the control panel
when calling about service or trouble-
shooting.
Model #_________________________
Serial #__________________________
AERCO International, Inc.
2ULWDQL'U
%ODXYHO, 1< 
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© AERCO International, Inc., 2010
The information contained in this document
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 mer-
chantability and fitness for a particular
application. AERCO International is not lia-
ble for errors appearing in this manual. Nor
for incidental or consequential damages
occurring in connection with the furnishing,
performance, or use of this material.

i
Esteem 399 Low NOx Installation and Maintenance Manual
GF-125
Contents
Chapter 1 Warnings and Cautions 1
Emergency Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Prolonged Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
IF YOU SMELL GAS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Chapter 2 Pre-Installation Items 4
Code Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Determining Product Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Boiler Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Recommended Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Residential Garage Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Boiler Freeze Protection Feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Chapter 3 Combustion Air and Venting 7
Combustion Air Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Potential contaminating products. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Areas likely to have contaminants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Ventilation and Combustion Air Requirements - Direct Vent. . . . . . . . . . . . . . . . . . . . . . . .8
Ventilation and Combustion Air Requirements - Category IV . . . . . . . . . . . . . . . . . . . . . . .8
Indoor Combustion Air. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Outdoor Combustion Air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Combination of Indoor and Outdoor Combustion Air . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Combustion Air and Vent Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Removal of an Existing Boiler from a Common Vent System . . . . . . . . . . . . . . . . . . . . . .11
Commonwealth of Massachusetts Installations Only . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Chapter 4 Unit Preparations 14
Handling Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Wall Mounting Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Wall Mounting Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Stud Wall Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Boiler Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Chapter 5 Boiler Piping 16
General Piping Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Pressure Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Low Water Cutoff Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Additional Limit Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Backflow Preventer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Boiler System Piping Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Expansion Tank and Makeup Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Diaphragm Expansion Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Closed-Type Expansion Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Circulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Sizing Primary Piping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

ii
Domestic Hot Water System Piping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
System Piping - Zone Circulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
System Piping - Zone Valves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
System Piping - Through Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
System Piping - Radiant Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
System Piping - Special Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
System Piping - Multiple Units Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Chapter 6 Installing Vent, Air Intake & Drain 27
Installing Vent and Combustion Air Intake. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Installing Condensate Drain Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Chapter 7 Gas Piping 29
Gas Supply Piping Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Natural Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Pipe Sizing - Natural Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Natural Gas Supply Pressure Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Propane Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Pipe Sizing - Propane Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Propane Gas Supply Pressure Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Chapter 8 Internal Wiring 33
General Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Control Module Circulator AMP Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Wiring Tool Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Internal Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Chapter 9 External Wiring 35
Installation Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Line Voltage Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Domestic Hot Water Aquastat Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Thermostat Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
CH and DHW Circulator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
System Circulator - Zone Valve Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
External Modulating Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Outdoor Reset Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Additional 24V Limit Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
External Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Chapter 10 Start-Up Preparation 39
Check Boiler System Water Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Water pH Level 6.0 to 8.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Water Hardness Less Than 7 Grains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Chlorinated Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Flush Boiler and Domestic System to Remove Sediment . . . . . . . . . . . . . . . . . . . . . . . . . 39
Check and Test Antifreeze. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

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Use of Antifreeze in the Boiler System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Filling the Boiler System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Check Low Water Cut-Off Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Check For Gas Leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Check Thermostat Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Inspect the Condensate Drain Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Chapter 11 Start-Up Procedures 42
Final Checks Before Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Esteem 399 Low NOx Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
If Esteem 399 Low NOx Does Not Start Correctly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
First Run Check of the Unit and System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Set Boiler CH Set Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
Operation Verification - Space Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
Operation Verification - Domestic Hot Water. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Chapter 12 Operating Instructions 47
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
TO TURN OFF GAS TO APPLIANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Boiler Control Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Standby Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
To temporarily place the burner into high fire test mode: . . . . . . . . . . . . . . . . . . . . . . 49
Parameter mode—Setting The Boiler Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Information Mode—Accessing Boiler Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Error (Hard Lockout) Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Chapter 13 Outdoor Reset Control 54
Mounting the Outdoor Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Wiring the Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Summer / Winter Switch at Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Adjusting Outdoor Reset Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
CH Maximum Boiler Operating Setpoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
CH Minimum Boiler Operating Setpoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
CH Reset Curve Coldest Day . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Entering MCBA Access Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Chapter 14 External Modulating Control 58
Wiring the Modulating Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
Parameter Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Programming of External Modulating Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Factory Parameter Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Chapter 15 Check-Out Procedures 60
Check-Out Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Chapter 16 Installation Record 61

iv
Chapter 17 Maintenance Schedule 62
Professional Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Owner Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Chapter 18 Maintenance Procedures 63
Attend to Reported Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Check Surrounding Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Inspect Burner Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Check System Piping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Clean Condensate Drain Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Check Ventilation Air Openings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Inspect Vent and Combustion Air Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Check Boiler System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Check Expansion Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Check Boiler Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Inspect Ignition Electrode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Check Ignition Wiring and Ground Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66
Check Control Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Check Control Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Check Burner Flame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Check Flame Signal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Check Combustion Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Check Flue Gas Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
Clean Heat Exchanger. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Start-up and Checkout Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Review With Owner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Chapter 19 Troubleshooting 69
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Control Module Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Soft Lockout Error Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Hard Lockout Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Insulation Handling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Appendices 87
Appendix A: Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Appendix B: Unit Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Appendix C: Pressure Drop Comparison Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93

1
Installers and operating personnel
MUST, at all times, observe all safety
regulations.
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.
IMPORTANT
This Instruction Manual is an integral
part of the product and must be main-
tained in legible condition. It must be giv-
en to the user by the installer and kept in
a safe place for future reference.
DANGER!
INDICATES THE PRESENCE OF AHAZARDOUS
SITUATION WHICH, IF IGNORED, WILL RESULT IN
DEATH, SERIOUS INJURY OR SUBSTANTIAL PROP-
ERTY DAMAGE.
WARNINGS!
MUST BE OBSERVED TO PREVENT SERIOUS IN-
JURY OR SUBSTANTIAL PROPERTY DAMAGE.
CAUTIONS!
Must be observed to prevent damage or
loss of operating effectiveness.
NOTICE
Indicates special instructions on instal-
lation, operation or maintenance, which
are important to equipment but not re-
lated to personal injury hazards.
WARNING!
BEFORE ATTEMPTING TO PERFORM ANY MAIN-
TENANCE ON THE UNIT, SHUT OFF ALL GAS AND
ELECTRICAL INPUTS TO THE UNIT.
WARNING!
THE EXHAUST VENT PIPE OF THE UNIT OPER-
ATES UNDER APOSITIVE PRESSURE AND THERE-
FORE MUST BE COMPLETELY SEALED TO PRE-
VENT LEAKAGE OF COMBUSTION PRODUCTS INTO
LIVING SPACES.
WARNING!
FLUIDS UNDER PRESSURE MAY CAUSE INJURY
OR DAMAGE TO EQUIPMENT WHEN RELEASED.
BESURE TO SHUT OFF ALL INCOMING AND OUT-
GOING WATER SHUT OFF VALVES. CAREFULLY
DECREASE ALL TRAPPED PRESSURES TO ZERO
BEFORE PERFORMING ANY BOILER MAINTE-
NANCE.
WARNING!
DONOT USE MATCHES, CANDLES, FLAMES, OR
OTHER SOURCES OF IGNITION TO CHECK FOR
GAS LEAKS.
GF-125
Chapter 1 Warnings and Cautions

2
Emergency Shutdown
CAUTION!
Many soaps used for gas pipe leak test-
ing are corrosive to metals. The piping
must be rinsed thoroughly with clean
water after leak checks have been com-
pleted.
CAUTION!
DO NOT use this boiler if any part has
been under water. Call a quali¿ed serv-
ice technician to inspect and replace
any part that has been underwater.
IMPORTANT
The Installer must identify and indicate
the location of the emergency shutdown
manual gas valve to operating person-
nel.
Emergency Shutdown
If overheating occurs or the gas supply fails
to shut off, close the manual gas shutoff valve
(Figure 1) located external to the unit.
Prolonged Shutdown
After prolonged shutdown, it is recommended
that the startup procedures in Chapter 10 of
this manual be performed, to verify all system
operating parameters. If there is an emergen-
cy, turn off the electrical power supply to the
AERCO boiler and close the manual gas valve
located upstream the unit. The installer must
identify the emergency shut-off device.
To shut Down the Unit
Turn the service switch on the Esteem 399
Low NOx control panel to “OFF”
Turn the external manual gas valve handle
clockwise to “CLOSE”.
Figure 1: Typical Manual Gas Shutoff Valve
GF-125

3
IF YOU SMELL GAS
DANGER!
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 ¿re department.
IMPORTANT
Installation and service must be per-
formed by a quali¿ed installer, service
agency or the gas supplier.
DANGER!
DONOT USE THIS APPLIANCE IF ANY PART
HAS BEEN UNDER WATER. IMMEDIATELY CALL
AQUALIFIED SERVICE TECHNICIAN TO INSPECT
THE APPLIANCE AND TO REPLACE ANY PART OF
THE CONTROL SYSTEM WHICH 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.
WARNING
DO NOT ADD COLD MAKE UP WATER WHEN THE
BOILER IS HOT. THERMAL SHOCK CAN CAUSE
POTENTIAL CRACKS IN THE HEAT EXCHANGER.
CAUTION
Avoid electrical shock by disconnecting
the electrical supply prior to performing
maintenance when servicing the boiler:
WARNING
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 GIV-
EN. FAILURE TO ADHERE TO THE GUIDELINES
WITHIN THESE MANUALS CAN RESULT IN SEVERE
PERSONAL INJURY, DEATH OR SUBSTANTIAL
PROPERTY DAMAGE.
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 installa-
tion or from the use of components or ¿ttings
not speci¿ed by AERCO International.
GF-125

4
Chapter 2 Pre-Installation Items
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 ¿tter, and if anti-
freeze is utilized, the installation of a re-
duced pressure backÀow preventer device
is required in the boiler’s cold water ¿ll or
make up water supply line.
• For installation in Massachusetts all direct
vented appliances must comply with the
guidelines as outlined on page 13.
• 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.
NOTICE
The Esteem 399 Low NOx boiler gas
manifold and gas controls meet the
safe lighting and other performance re-
quirements as speci¿ed in ANSI Z21.13
latest edition.
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 com-
bustion 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 Low NOx is free of any com-
bustible materials, gasoline and other flam-
mable liquids.
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 Low NOx and its con-
trols are protected from dripping or spraying
water during normal operation or service.
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.
GF-125

5
Boiler Replacement
Boiler Replacement
If the Esteem 399 Low NOx 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 Warning on ”Handling Previously Fired
Combustion Chamber Insulation” on page 67
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 Concentric Vent System Installation
Supplement GF-125V for vent clearance
requirements.
To provide service access to the unit it is rec-
ommended that the following clearances be
maintained:
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
IFTHE 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. SEEP-
AGE 8 FOR REQUIREMENTS.
GF-125

66
NOTICE
When maintaining zero clearance or
less than recommended clearances,
some product labeling may become
hidden and unreadable.
WARNING
WHEN INSTALLING THE ESTEEM 399 LOW NOX
IN ACONFINED SPACE, SUFFICIENT AIR MUST
BE PROVIDED FOR PROPER COMBUSTION AND
VENTING AND TO ALLOW, UNDER NORMAL OPER-
ATING CONDITIONS, PROPER AIR FLOW AROUND
THE PRODUCT TO MAINTAIN AMBIENT TEMPERA-
TURES WITHIN SAFE LIMITS TO COMPLY WITH
THE NATIONAL FUEL GAS CODE NFPA 54 -
LATEST EDITION.
Residential Garage Installations
When installing the Esteem 399 Low NOx
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.
Boiler Freeze Protection Feature
The boiler control has a freeze protection fea-
ture built in. This feature monitors the boiler
temperature and responds as follows when no
call for heat is present:
• 46ºF Boiler circulator is ON
• 38ºF Boiler circulator is ON and burner
operates at low fire
• 50ºF Burner OFF and boiler circulator
operates for approximately 10 minutes
CAUTION
The boiler freeze protection feature is
disabled during a hard lockout, how-
ever 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 ex-
posed to water temperatures of 46ºF or
less. See “Chapter 5 Boiler Piping” on
page16for primary/secondarypipingex-
amples. See Chapter 10 for antifreeze
guides.
GF-125GF-125

7
Combustion Air Contamination
WARNING
IFTHE ESTEEM 399 LOW NOXCOMBUSTION
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 COMBUS-
TION AIR WILL DAMAGE THE UNIT AND ITS BURN-
ER SYSTEM, RESULTING IN POSSIBLE SEVERE
PERSONAL INJURY, DEATH OR SUBSTANTIAL
PROPERTY DAMAGE.
WARNING
DONOTOPERATE AN ESTEEM 399 LOW NOX
IF ITS COMBUSTION AIR INLET IS LOCATED NEAR
ALAUNDRY ROOM OR POOL FACILITY. THESE
AREAS WILL ALWAYS CONTAIN HAZARDOUS
CONTAMINANTS.
Pool and laundry products and common house-
hold and hobby products often contain fluorine
or chlorine compounds. When these chemi-
cals 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 sur-
rounding 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 out-
side area free of these chemicals per Chapter
5 of this installation manual.
Potential contaminating products
• Spray cans containing chloro/Àuorocar-
bons
• 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
• Adhesives and other similar products
Areas likely to have contaminants
• Dry cleaning / laundry areas and establish-
ments
• Beauty salons
• Metal fabrication shops
• Swimming pools and health spas
• Refrigeration Repair shops
• Photo processing plants
• Auto body shops
• Plastic manufacturing plants
• Furniture re¿nishing areas and establish-
ments
• New building construction
• Remodeling areas
• Garages with workshops
The above lists are NOT comprehensive.
Installer, The end user and service personnel
are responsible for certifying the safety of any
and all materials that may affect the quality of
the combustion air.
Chapter 3 Combustion Air and Venting
GF-125

8
Ventilation and Combustion Air Requirements - Direct Vent
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 399 Low NOx , in which the minimum
service clearances are maintained as listed on
page 5, no ventilation openings are required.
For Direct Vent, zero clearance installations
involving only the Esteem 399 Low NOx , 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.
WARNING
THE SPACE MUST BE PROVIDED WITH VENTILA-
TION / COMBUSTION AIR OPENINGS PROPERLY
SIZED FOR ALL MAKE-UP AIR REQUIREMENTS
(EXHAUST FANS, CLOTHES DRYERS, ETC.) AND
THE TOTAL INPUT OF ALL APPLIANCES LOCATED
IN THE SAME SPACE AS THE ESTEEM 399 LOW
NOX, EXCLUDING THE INPUT OF ADIRECT
VENT ESTEEM 399 LOW NOXWHICH USES
COMBUSTION AIR DIRECTLY FROM THE OUTSIDE,
THUS ADDITIONAL FREE AREA FOR THE OPEN-
INGS IS NOT REQUIRED. FAILURE TO PROVIDE
PROPERLY SIZED OPENINGS COULD RESULT IN
SEVERE PERSONAL INJURY, DEATH OR PROP-
ERTY DAMAGE.
Ventilation and Combustion Air
Requirements - Category IV
A Category IV appliance uses uncontaminated
indoor or outdoor air (surrounding the appli-
ance) for combustion.
Piping uncontaminated combustion air directly
from the outdoors to the appliance is recom-
mended. This reduces the risks associated with
indoor contaminates, flammable vapors and
tight housing construction. This practice also
promotes higher system efficiency.
For installations in which 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,
as referenced in this chapter of the manual and
titled Methods of Supplying Combustion Air to
a Space.
WARNING
THE SPACE MUST BE PROVIDED WITH VENTILA-
TION / COMBUSTION AIR OPENINGS PROPERLY
SIZED FOR ALL MAKE-UP AIR REQUIREMENTS
(EXHAUST FANS, CLOTHES DRYERS, ETC.) AND
THE TOTAL INPUT OF ALL APPLIANCES, INCLUD-
ING THE ESTEEM 399 LOW NOXWHEN LOCAT-
ED IN THE SAME SPACE. FAILURE TO PROVIDE
PROPERLY SIZED OPENINGS COULD RESULT IN
SEVERE PERSONAL INJURY, DEATH OR PROP-
ERTY DAMAGE.
GF-125

9
Ventilation and Combustion Air Requirements - Category IV
Methods of Supplying Combustion Air to
a Confined Space - Category IV
INDOOR COMBUSTION AIR
NOTICE
The methods listed in this section for ac-
cessing Indoor Combustion Air assume
that the in¿ltration rate is adequate and
not less than .40 ACH. For in¿ltration
rates less than .40 ACH, reference the
NFPA 54 National Fuel Gas Code for
additional guidance.
Opening Size and Location
Openings used to connect indoor spaces shall
be sized and located in accordance with the
following see Figure 2
• Combining spaces on the same story.
Each opening shall have a minimum free
area of 1 sq. in./1000 Btu/hr of the total
input rating of all gas utilization equip-
ment in the space, but not less than
100 sq. inches. One opening shall com-
mence within 12 inches of the top, and
one opening shall commence within 12
inches of the bottom of the enclosure.
The minimum dimension of air openings
shall be not less than 3 inches.
• Combining spaces in different stories.
The volumes of spaces in different sto-
ries shall be considered as communi-
cating spaces where such spaces are
connected by one or more openings in
doors or floors having a total minimum
free area of 2 sq. in./1000 Btu/hr of total
input rating of all gas utilization equip-
ment.
OUTDOOR COMBUSTION AIR
Isolating the combustion appliance room from
the rest of the building and bringing in uncon-
taminated outside air for combustion and venti-
lation is always preferred.
Opening Size and Location
The minimum dimension of air openings shall
be not less than 3 inches
Openings used to supply combustion and
ventilation air shall be sized and located in
accordance with the following:
One Permanent Opening Method. See Figure
3
One permanent opening, commencing within
12 inches of the top of the enclosure, shall be
provided. The equipment shall have clearances
of at least 1 inch from the sides and 6 inches
from the front of the appliance. The opening
shall directly communicate with the outdoors or
shall communicate through a vertical or hori-
zontal duct to the outdoors or spaces that freely
communicate with the outdoors and shall have
a minimum free area of the following:
Figure 2: :
All Combustion Air from Adjacent Indoor Spaces
Through Indoor Combustion Openings
GF-125

10
Ventilation and Combustion Air Requirements - Category IV
• 1 sq. in./3000 Btu/hr of the total input
rating of all equipment located in the
enclosures, and
• Not less than the sum of the areas of all
vent connectors in the space.
Two Permanent Openings Method.
Two permanent openings, one commencing
within 12 inches of the top and one commenc-
ing within 12 inches of the bottom of the enclo-
sure, shall be provided. The openings shall
communicate directly, or by ducts, with the
outdoors or spaces that freely communicate
with the outdoors, as follows:
• Where directly communicating with the
outdoors or where communication to the
outdoors is through vertical ducts, each
opening shall have a minimum free area of
1 sq. in./4000 Btu/hr of total input rating for
all equipment in the enclosure.
See Figure 4.
• Where communicating with the outdoors
is through horizontal ducts, each opening
shall have a minimum free area of not less
than 1 sq. in./2000 Btu/hr of total input rat-
ing of all equipment in the enclosure. See
Figure 5.
Figure 3: :
All Combustion Air from Outdoors Through One
Permanent Air Opening
Figure 4: :
All Combustion Air from Outdoors Through
Ventilated Attic
Figure 5: :
All Combustion Air from Outdoors through
Horizontal Ducts
GF-125

11
Combustion Air and Vent Piping
COMBINATION OF INDOOR AND OUTDOOR
COMBUSTION AIR
Indoor Openings: Where used, openings con-
necting the interior spaces shall comply with
the Indoor Combustion Air section on page 9.
Outdoor Opening(s) Location. Outdoor
opening(s) shall be located in accordance with
the Outdoor Combustion Air section.
Outdoor Opening(s) Size. Outdoor opening(s) shall
be calculated in accordance with the following:
• The ratio of the interior spaces shall be
the available volume of all communicating
spaces divided by the required volume.
• The outdoor size reduction factor shall be
1 minus the ratio of interior spaces.
• The minimum size of outdoor opening(s)
calculated in accordance with the above
outdoor air section multiplied by the reduc-
tion factor. The minimum dimension of air
openings shall not be less than 3 in.
DANGER!
DONOTINSTALL THE ESTEEM 399 LOW NOX
INTO ACOMMON VENT WITH OTHER GAS OR OIL
APPLIANCES. THIS MAY CAUSE FLUE GAS SPILL-
AGE OR APPLIANCE MALFUNCTION, RESULTING
IN POSSIBLE SEVERE PERSONAL INJURY, DEATH
OR SUBSTANTIAL PROPERTY DAMAGE.
Combustion Air and Vent Piping
DANGER!
COMBUSTION AIR AND VENT PIPING MUST BE
SEALED GAS TIGHT AND MEET ALL PROVIDED IN-
STRUCTIONS AND APPLICABLE CODES, FAILURE
TO COMPLY WILL RESULT IN SEVERE PERSONAL
INJURY OR DEATH.
The Esteem 399 Low NOx requires a Category
IV venting system, which is designed for pres-
surized venting and condensate.
The Esteem 399 Low NOx is certified per
ANSI Z21.13 as a Category IV or Direct Vent
(sealed combustion) appliance. A Category
IV appliance utilizes uncontaminated indoor
or outdoor air (surrounding the appliance) for
combustion. A Direct Vent appliance utilizes
uncontaminated outdoor air (piped directly to
the appliance) for combustion.
Piping uncontaminated combustion air directly
from the outdoors to the appliance is recom-
mended. This reduces the risks associated with
indoor contaminates, flammable vapors and
tight housing construction. This practice also
promotes higher system efficiency.
NOTICE
Install combustion air and vent pipe as
detailed in the Esteem 399 Low NOx
Vent Supplement included in the boiler
installation envelope. Refer to optional
vent kit instructions for addition vent in-
stallation instructions.
Removal of an Existing Boiler from a
Common Vent System
DANGER!
DONOTINSTALL THE ESTEEM 399 LOW NOX
INTO ACOMMON VENT WITH OTHER GAS OR OIL
APPLIANCES. THIS MAY CAUSE FLUE GAS SPILL-
AGE OR APPLIANCE MALFUNCTION, RESULTING
IN POSSIBLE SEVERE PERSONAL INJURY, DEATH
OR SUBSTANTIAL PROPERTY DAMAGE.
NOTICE
When an existing boiler is removed
from a common venting system, the
common venting system is likely to be
too large for proper venting of the re-
maining appliances.
At the time of removal of an existing boiler,
the following steps shall be followed with each
appliance remaining connected to the com-
GF-125

12
Removal of an Existing Boiler from a Common Vent System
mon venting system placed in operation, while
the other appliances remaining connected to
the common venting system are not in opera-
tion.
• Seal any unused openings in the common
venting system.
• Visually inspect the venting system for
proper size and horizontal pitch and de-
termine there is no blockage or restriction,
leakage, corrosion and other de¿ciencies
which could cause an unsafe condition.
• Insofar as is practical, close all building
doors and windows and all doors between
the space in which the appliances remain-
ing connected to the common venting
system are located and other spaces of
the building. Turn on clothes dryers and
any appliance not connected to the com-
mon venting system. Turn on any exhaust
fans, such as range hoods and bathroom
exhausts, so they will operate at maximum
speed. Do not operate a summer exhaust
fan. Close ¿replace dampers.
• Operate the appliance being inspect-
ed. Follow the lighting instructions. Adjust
thermostat so appliance will operate con-
tinuously.
• Test for spillage at the draft hood relief
opening after 5 minutes of main burner op-
eration. Use the Àame of a match or candle,
or smoke from a cigarette, cigar or pipe.
• After it has been determined that each ap-
pliance remaining connected to the com-
mon venting system properly vents when
tested as outlined above, return doors,
windows, exhaust fans, ¿replace dampers,
and any other gas-burning appliance to
their previous condition of use.
• Any improper operation of the common
venting system should be corrected so the
installation conforms with the National Fuel
Gas Code, ANSI Z223.1/NFPA 54 and/or
CAN/CGA B149, Installation codes. When
re-sizing any portion of the common vent-
ing system, the common venting system
should be re-sized to approach the appro-
priate tables in Part II of the National Fuel
Gas Code ANSI Z223.1/NFPA 54 and/or
CAN/CGA B149, Installation codes.
GF-125

13
For direct-vent appliances, mechanical-vent
heating appliances or domestic hot water
equipment, where the bottom of the vent ter-
minal and the air intake is installed below four
feet above grade the following requirements
must be satisfied:
• 1. If there is not one already present,
on each floor level where there are
bedroom(s), a carbon monoxide detec-
tor and alarm shall be placed in the liv-
ing area outside the bedroom(s). The
carbon monoxide detector shall comply
with NFPA 720 (2005 Edition).
• 2. A carbon monoxide detector shall
also be located in the room that houses
the appliance or equipment and shall:
• a. Be powered by the same
electrical circuit as the appliance
or equipment such that only one
service switch services both the
appliance and the carbon monoxide
detector;
• b. Have battery back-up power;
• c. Meet ANSI/UL 2034
Standards and comply with NFPA
720 (2005 Edition); and
• d. Have been approved and
listed by the Nationally Recognized
Testing Laboratory as recognized
under 527 CMR.
• 3. A Product-approved vent terminal
must be used, and if applicable, a
Product-approved air intake must be
used. Installation shall be in strict com-
pliance with the manufacturer’s instruc-
tions. A copy of the installation instruc-
tions shall remain with the appliance
or equipment at the completion of the
installation.
• 4. A metal or plastic identification plate
shall be mounted at the exterior of the
building, four feet directly above the
location of vent terminal. The plate shall
be of sufficient size to be easily read
from a distance of eight feet away, and
read “Gas Vent Directly Below”.
NOTICE
Installer must provide tag identi¿cation
plate and ensure the lettering meets
code requirements.
For direct-vent appliances, mechanical-vent
heating appliances or domestic hot water
equipment, where the bottom of the vent termi-
nal and the air intake are installed above four
feet above grade the following requirements
must be satisfied:
• 1. If there is not one already present,
on each floor level where there are
bedroom(s), a carbon monoxide detec-
tor and alarm shall be placed in the liv-
ing area outside the bedroom(s). The
carbon monoxide detector shall comply
with NFPA 720 (2005 Edition).
• 2. A carbon monoxide detector shall:
• a. Be located in the room that
houses the appliances or equip-
ment;
• b. Be either hard wired or bat-
tery powered or both; and
• c. Shall comply with NFPA 720
(2005 Edition)
• 3. A Product-approved vent terminal
must be used, and if applicable, a
Product-approved air intake must be
used. Installation shall be in strict com-
pliance with the manufacturer’s instruc-
tions. A copy of the installation instruc-
tions shall remain with the appliance
or equipment at the completion of the
installation.
Commonwealth of Massachusetts Installations Only
GF-125

14
Handling Instructions
The Esteem 399 Low NOx is generally easier
to handle and maneuver once removed from
the shipping carton.
To remove the shipping carton:
CAUTION
Use care not to lift the unit from, or
place the unit on the front plastic con-
trol panel, damage can occur. Use care
not to drop, bump or rotate the boiler
upside down, as damage to the boiler
will result.
1. Remove any shipping straps and open
the side of the shipping carton.
2. Slide the unit with the foam inserts out of
the carton.
3. Discard all packing materials.
Wall Mounting Installation
The Esteem 399 Low NOx should be wall
mounted using the bracket provided with
the boiler. The Esteem 399 Low NOx is not
designed for floor installation. If floor installa-
tion is required an optional floor stand is avail-
able through AERCO International.
WARNING
THE WALL USED FOR MOUNTING THE ESTEEM
399 LOW NOXMUST BE VERTICALLY PLUMBED
AND CAPABLE OF SUPPORTING AMINIMUM 250
POUNDS [115 KG] FOR ESTEEM 399 LOW NOX
. FAILURE TO COMPLY WITH THESE REQUIRE-
MENTS COULD RESULT IN PERSONAL INJURY,
DEATH OR SUBSTANTIAL PROPERTY DAMAGE.
Wall Mounting Guidelines
• The boiler is heavy and bulky. A minimum
of 2 people is required for mounting the
boiler.
• DO NOT mount or attempt to mount the
wall bracket to hollow sheet rock or lath
walls using anchors. Only install boiler to
studs or equivalent wood structure.
• The wall-mounting bracket is designed
for stud spacing of 12 inch or 16 inch on
centers. For unconventional stud spacing,
a solid / secure mounting surface must be
provided for installation of the bracket.
• For mounting on wood studs, install the
bracket using the lag screws provided with
the boiler. Ensure both lag screws are
installed securely in the studs.
• For mounting on metal studs, install the
bracket to the studs using 3/16” toggle
bolts and washers.
• For mounting on solid walls (rock, concrete,
brick, cinder block, etc.), install the wall
bracket using anchors (double expansion
shields) and bolts with washers provided
with the boiler.
WARNING
USE EXTREME CARE NOT TO DROP THE BOILER
OR CAUSE BODILY INJURY WHILE LIFTING OR
MOUNTING THE BOILER ONTO THE BRACKET.
ONCE MOUNTED VERIFY THAT THE BOILER IS
SECURELY ATTACHED TO THE BRACKET AND
WALL. FAILURE TO COMPLY WITH THE ABOVE
GUIDELINES COULD RESULT IN PROPERTY DAM-
AGE, PERSONAL INJURY OR DEATH.
Stud Wall Installation
• To distribute the weight of the boiler evenly
when mounting onto a stud wall it is rec-
ommended to use the Esteem 399 Low
NOx Wall Frame kit.
• When using the wall frame to mount the
boiler reference the kit installation instruc-
tions and ensure the frame is securely
fastened to the wall.
• If the structure of wall is questionable,
in supporting a minimum weight of 250
pounds [115 kg.], it is recommended to use
the optional Àoor stand.
Wall Bracket Installation - Solid Walls
Chapter 4 Unit Preparations
GF-125