A.O. Smith WATER HEATERS User Manual (English)

Questions and Answers:

S
Susan LiJul 29, 2025
Why is my A.O. Smith Water Heater not producing enough hot water?
- S
  Sarah OneillJul 29, 2025
  There could be several reasons for this. The power supply to the heater might not be on, so check the disconnect switch. The thermostat might be set too low. The heater might be undersized, so try to reduce hot water use. Incoming water might be unusually cold, especially in winter, so allow more time for the water to reheat. There could also be leaks from pipes or fixtures, so have a plumber check for repairs. Finally, the high-temperature limit switch may be activated; contact your dealer to determine the cause.
R
Ryan WilsonAug 3, 2025
What to do if A.O. Smith Water Heater is leaking?
- T
  Thomas DuncanAug 3, 2025
  If you notice water leaks, first check the hot and cold supply connections, relief valve, and drain valve to ensure they are properly sealed and tighten threaded connections. Also, inspect other appliances and water lines near the water heater for any leakage.
D
David FletcherAug 8, 2025
What to do if A.O. Smith Water Heater is too hot?
- M
  Miranda PruittAug 8, 2025
  If the water is too hot, the thermostat may be set too high. Refer to temperature regulation. Also, the high-temperature limit switch may be activated; contact your dealer to determine the cause and see temperature regulation.
M
Maria MayAug 13, 2025
Why is my A.O. Smith Water Heater leaking from the temperature and pressure relief valve?
- B
  bmcclainAug 13, 2025
  A leaking temperature and pressure relief valve can be due to thermal expansion in a closed water system, in which case you should install a thermal expansion tank, making sure not to plug the T&P valve. It could also be due to an improperly seated valve, so check the relief valve for proper operation, again being sure not to plug the T&P valve.
T
Terry MendozaAug 18, 2025
How to fix A.O. Smith Water Heater making sounds?
- M
  Miss Lori BowmanAug 18, 2025
  Water heater noises can be attributed to scale accumulation on the elements or sediment build-up on the tank bottom. For scale accumulation, contact your dealer to clean or replace the elements. For sediment build-up, drain and flush the heater thoroughly, then refill it.
A
Adrian MorenoAug 22, 2025
Why does my A.O. Smith Water Heater have hot water odors?
- R
  Richard GarciaAug 23, 2025
  Hot water odors can be caused by high sulfate or mineral content in the water supply or bacteria in the water supply. If it is the high sulfate or mineral content, drain and flush the heater thoroughly, then refill it. If it is bacteria, chlorinate the water supply.

A.O. Smith WATER HEATERS Specifications

General

Brand	A. O. Smith
Category	Water Heater
Capacity	Varies (e.g., 40, 50, 75 gallons)
Warranty	Varies (e.g., 6, 10, or 12 years)
Voltage	120V, 240V (Electric)
Fuel Type	Electric or Natural Gas/Propane
Weight	Varies by model

Summary

SAFE INSTALLATION. USE AND SERVICE

IMPORTANT DEFINITIONS

Provides definitions for Qualified Installer and Service Agency.

GENERAL SAFETY

WARNING: Explosion Hazard

Warns about overheated water causing tank explosion and requires a proper relief valve.

WARNING: Electrical Safety

Advises turning off electrical supply before servicing to prevent injury or damage.

INTRODUCTION

PREPARING FOR THE INSTALLATION

Emphasizes reading the entire manual and following safety rules for proper operation.

WIRING DIAGRAMS

Electrical Safety Warning

Warns to turn off power before servicing electrical components to prevent injury.

MIXING VALVE USAGE

Hot Water Scald Hazard

Explains the risk of scalding from hot water, especially for vulnerable groups.

LOCATING THE NEW WATER HEATER

LOCATION CONSIDERATIONS

Details criteria for selecting a safe and economical indoor location, including clearance and drainage.

INSULATION BLANKETS

Discusses the use and precautions for insulation blankets on water heaters.

INSTALLING THE NEW WATER HEATER

INSTALLATION SCALD HAZARD

Warns about severe burns from water over 125°F and advises checking temperature.

TEMPERATURE-PRESSURE RELIEF VALVE OPERATION

WARNING: Explosion Hazard

Warns about explosion risks if the T&P valve is not compliant or is blocked.

Discharge Pipe Requirements

Specifies how the discharge pipe for the relief valve should be installed to prevent damage.

FILLING THE WATER HEATER

FILLING TANK PROPERTY DAMAGE

Advises filling the tank completely with water before operation to prevent tank damage.

TEMPERATURE REGULATION

THERMOSTAT ADJUSTMENT ELECTRICAL SAFETY

Advises turning off power before adjusting thermostat to prevent electrocution.

BURN TIME ESTIMATES

Shows the relationship between water temperature and time to cause burns on adult skin.

THERMAL EXPANSION

THERMAL EXPANSION PROPERTY DAMAGE

Explains how thermal expansion in closed systems can increase pressure and cause damage.

OPERATIONAL CONDITIONS

SMELLY WATER CAUSES

Explains causes of smelly hot water and potential solutions like anode rod replacement.

ANODE ROD INSPECTION

ANODE ROD INSPECTION PROPERTY DAMAGE

Details the importance of anode rod inspection for tank corrosion protection.

TEMPERATURE-PRESSURE RELIEF VALVE OPERATION

T&P VALVE BURN HAZARD

Warns about the hazard of hot water discharge from the relief valve.

DRAINING

DRAINING CAUTION BURN HAZARD

Advises caution when draining to avoid burns from hot water discharge.

DRAIN VALVE WASHER REPLACEMENT

DRAIN VALVE WASHER REPLACEMENT PROCEDURE

Provides step-by-step instructions for replacing the drain valve washer.

LEAKAGE CHECKPOINTS

LEAKAGE CHECKPOINTS ELECTRICAL SAFETY

Reiterates turning off power before checking for leaks to prevent injury.

REPAIR PARTS LIST

Part Identification

Lists key parts of the water heater with corresponding numbers for identification and ordering.

TROUBLESHOOTING GUIDELINES

Common Problems and Solutions

Provides a guide to identify and resolve common water heater issues like leaks, odors, and temperature problems.

RESIDENTIAL ELECTRIC WARRANTY

Warranty Terms and Conditions

Outlines the terms, conditions, and exclusions of the residential electric water heater warranty.

SERVICE AND LABOR RESPONSIBILITY

Claim Procedure

Details how to initiate a warranty claim and what costs are the owner's responsibility.

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A.O. Smith WATER HEATERS User Manual

Table of Contents

Questions and Answers:

A.O. Smith WATER HEATERS Specifications

Summary

SAFE INSTALLATION. USE AND SERVICE

IMPORTANT DEFINITIONS

GENERAL SAFETY

WARNING: Explosion Hazard

WARNING: Electrical Safety

INTRODUCTION

PREPARING FOR THE INSTALLATION

WIRING DIAGRAMS

Electrical Safety Warning

MIXING VALVE USAGE

Hot Water Scald Hazard

LOCATING THE NEW WATER HEATER

LOCATION CONSIDERATIONS

INSULATION BLANKETS

INSTALLING THE NEW WATER HEATER

INSTALLATION SCALD HAZARD

TEMPERATURE-PRESSURE RELIEF VALVE OPERATION

WARNING: Explosion Hazard

Discharge Pipe Requirements

FILLING THE WATER HEATER

FILLING TANK PROPERTY DAMAGE

TEMPERATURE REGULATION

THERMOSTAT ADJUSTMENT ELECTRICAL SAFETY

BURN TIME ESTIMATES

THERMAL EXPANSION

THERMAL EXPANSION PROPERTY DAMAGE

OPERATIONAL CONDITIONS

SMELLY WATER CAUSES

ANODE ROD INSPECTION

ANODE ROD INSPECTION PROPERTY DAMAGE

TEMPERATURE-PRESSURE RELIEF VALVE OPERATION

T&P VALVE BURN HAZARD

DRAINING

DRAINING CAUTION BURN HAZARD

DRAIN VALVE WASHER REPLACEMENT

DRAIN VALVE WASHER REPLACEMENT PROCEDURE

LEAKAGE CHECKPOINTS

LEAKAGE CHECKPOINTS ELECTRICAL SAFETY

REPAIR PARTS LIST

Part Identification

TROUBLESHOOTING GUIDELINES

Common Problems and Solutions

RESIDENTIAL ELECTRIC WARRANTY

Warranty Terms and Conditions

SERVICE AND LABOR RESPONSIBILITY

Claim Procedure

Related product manuals