A.O. Smith 750 Water Heater User Manual


 
4
SAFE INSTALLATION, USE, AND SERVICE .......................................................................................................................................2
GENERAL SAFETY ................................................................................................................................................................................ 3
TABLE OF CONTENTS .........................................................................................................................................................................4
Installation Requirements for the Commonwealth of Mass ...................................................................................................................5
Wiring Diagram....................................................................................................................................................................................6-7
Schematic Diagram ................................................................................................................................................................................8
Lighting and Operating Instructions.......................................................................................................................................................9
Water Temperature Regulation ............................................................................................................................................................10
Control System ................................................................................................................................................................................ 10-11
Operating Sequence............................................................................................................................................................................. 11
UIM Operating Procedures ..................................................................................................................................................................12
Operating Setpoint Adjustment Procedure ..........................................................................................................................................14
TROUBLESHOOTING IGNITION SYSTEM ......................................................................................................................................... 16
Troubleshooting Gas Valve..............................................................................................................................................................17
PREVENTATIVE MAINTENANCE ........................................................................................................................................................17
Main Burners....................................................................................................................................................................................17
Relief Valve ......................................................................................................................................................................................18
Combustion Air Filter .......................................................................................................................................................................18
Blower Compartment........................................................................................................................................................................18
Burner Maintenance ......................................................................................................................................................................... 18
Condensate Removal System ......................................................................................................................................................... 18
Venting Maintenance........................................................................................................................................................................19
Heat Exchanger Preventive Maintenance .......................................................................................................................................19
Tube Cleaning Procedure................................................................................................................................................................19
REPLACEMENT PARTS ...................................................................................................................................................................... 19
LIMITED WARRANTY .......................................................................................................................................................................... 23
CONTENTS
INTRODUCTION
This design complies with the current edition of the ANSI
Z21.13 low-pressure boiler standard.
Compliance under this standard implies that when the boiler
underwent test, the gas manifold and control assembly provided
on the boiler met safe lighting and other performance criteria.
Detailed installation diagrams are found in this manual. These
diagrams will serve to provide the installer a reference for the
materials and methods of piping necessary. It is essential that
all water, gas piping and wiring be installed as shown on the
diagrams. You should thoroughly read and understand this
manual before installation and/or operation of this boiler.
The factory warranty will be
void if the boiler(s) have been
improperly installed or operated.
AL 29-4C
®
is a registered trademark of Allegheny Ludlum
Corporation.
In addition to these instructions, the boiler(s) shall be installed in
accordance with those installation regulations in force in the local
area where the installation is to be made. These shall be carefully
followed in all cases. Authorities having jurisdiction should be
consulted before installations are made.
In the absence of local codes, the installation must comply with
the current editions, as follows:
In the United States:
The National Fuel Gas Code, ANSI Z223.1/NFPA 54 and the
National Electric Code, NFPA 70.