A.O. Smith DB/DW-720-1810 warranty Contents, Foreword, Replacement Parts

CONTENTS

Page Page

FOREWORD	2
REPLACEMENT PARTS	2-3
ROUGH-IN DIMENSIONS/CAPACITIES	3-4
Installation Clearances	3
Levelling	3
FEATURES	5
Safety Relief Valves	5
Electronic Intermittent PIlot Ignition Control	5
Manual Reset High Temperature Safety Limit Control	5
Automatic Reset High Temperature Control	6
Thermal Balancer	6
Safety Flow Switch	6
INSTALLATION INSTRUCTIONS	7
Required Ability	7
Location	7
Air Requirements	7-8
Venting the Boiler	8-9
Gas Connections	9
Purging	10-11
High Altitude Installations	11
Wiring Connections	11-12
Servicing Wiring And/Or Control	12
SYSTEM EQUIPMENT INSTALLATION	12
Water Supply Line	12
Expansion Tank	12
Vent Valves	12
System Headers	12
Cooling Piping	12
Safety Flow Switch	12-13
Circulating Pump	13-14

Low Water Cutoff	14
Tank Temperature Control	14
SYSTEM INSTALLATION	14
Conventional Space Heating Installation	14-15
Installation As Boiler Replacement	15-17
Linear-Temp Space Heating Applications	17
Linear-Temp Space Heating Installations	17-20
Wiring and Schematic Diagrams	21-26
HOT WATER SUPPLY APPLICATIONS	27-32
Water Line Connections	27
Hard Water Conditions	27
START-UP AND OPERATING INSTRUCTIONS	32
LIGHTING AND OPERATING INSTRUCTIONS	33
Internal Contaminants	34
Precautions	34
Checking and Adjusting the Input	34
Pilot Burner	34
Main Burner	34-35
PRE-TROUBLESHOOTING	35
TROUBLESHOOTING	35-38
GENERAL MAINTENANCE	39
Relief Valve	39
Venting Maintenance	39
Heat Exchanger Preventive Maintenance	39
Deliming	39-40
Deliming Solvents	40
Removing Light Deposits of Scale	40
Removal of an Existing Boiler From A Common Venting
System	40
LIMITED WARRANTY	41

FOREWORD

CAUTION

TEXT PRINTED OR OUTLINED IN RED CONTAINS INFORMATION RELATIVE TO YOUR SAFETY. PLEASE READ THOROUGHLY BEFORE USING APPLIANCE.

Detailed installation diagrams are in this manual. These diagrams will serve to provide the installer with a reference for the materials and method of piping suggested. IT IS NECESSARY THAT ALL WATER AND GAS PIPING AND THE ELECTRICAL WIRING BE INSTALLED AND CONNECTED AS SHOWN IN THE DIAGRAMS.

CHECK THE DIAGRAMS THOROUGHLY BEFORE STARTING INSTALLATION TO AVOID POSSIBLE ERRORS AND TO MINIMIZE TIME AND MATERIALS COST.

This design complies with the latest edition of the ANSI Z21.13 CSA 4.9 low-pressure boiler.

Particular attention should be given to the installation of thermometers at the locations indicated in the diagrams as these are necessary for checking the operation of the boiler.

MAKE SURE THE GAS ON WHICH THE BOILER WILL OPERATE IS THE SAME AS THAT SPECIFIED ON THE UNIT RATING PLATE.

The boiler installation must conform to these instructions and the requirements of the local authority having jurisdiction.

Where required by the authority having jurisdiction, the installation must conform to the Standard for Controls and Safety Devices for Automatically Fired Boilers, ANSI/ASME CSD-1.

In the absence of local code requirements, the boiler installation must conform to the most current National Fuel Gas Code, ANSI Z223.1 and/or CAN/CSA-B149.1-00 installation codes.

These manuals can be purchased from the CSA International, 8501 East Pleasant Valley Road, Cleveland, OH 44131 or 178 Rexdale Boulevard, Toronto, Ontario Canada, M9W 1R3.

REPLACEMENT PARTS

Replacement parts may be ordered through A. O. Smith dealers, authorized servicers or distributors. Refer to the Yellow Pages for where to call or contact (in United States) the A.O. Smith Water Products Company, 5621 West 115th Street, Alsip, IL 60803, 1-800-433-2545 or (in Canada) A.O. Smith Enterprises Ltd., 768 Erie Street, Stratford, Ontario, Canada N5A 6T3, 800-265-8520. When ordering parts be sure to state the quantity, part number and description of the item including the complete model and serial number as it appears on the product. Refer to the parts lists for more information.

For Technical Assistance call A.O. Smith Technical Information Center at 1-800-527-1953.

WARNING

THE INLET/OUTLET WATER MANIFOLD ON YOUR A. O. SMITH UNIT INCORPORATES AN “O RING" WATER SEAL ASSEMBLY. THE MANIFOLD IS NOT DESIGNED TO SUPPORT THE WEIGHT OF THE WATER PIPING SYSTEM. AS ON ALL BOILER INSTALLATIONS, SPECIAL CARE MUST BE TAKEN TO ENSURE PROPER SUPPORT.

WARNING

UNDER NO CIRCUMSTANCES SHOULD THE EQUIPMENT ROOM WHERE THE BOILER IS INSTALLED EVER BE UNDER NEGATIVE PRESSURE. PARTICULAR CARE MUST BE TAKEN WHEN EXHAUST FANS, COMPRESSORS, AIR HANDLING EQUIPMENT, ETC., MAY INTERFERE WITH THE COMBUSTION AND VENTILATION AIR SUPPLIES OF THIS BOILER.

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