Ao Smith Water Heater Manual: A Comprehensive Guide
Welcome! This manual provides essential guidance for your Ao Smith water heater, covering installation, operation, troubleshooting, and maintenance for optimal performance.
It’s designed to help you safely fix common issues and understand your appliance’s features, ensuring years of reliable hot water.
Understanding Your Ao Smith Water Heater
Ao Smith water heaters are renowned for their durability and efficiency, offering a range of models – electric, gas, and tankless – to suit diverse needs. This section introduces the core components and operational principles common across many Ao Smith units.
Familiarizing yourself with these basics will empower you to perform routine maintenance and accurately diagnose potential problems. Key elements include the tank (for storage models), heating mechanism (electric elements or gas burner), thermostat for temperature control, and the temperature & pressure relief valve for safety.
Understanding how these parts interact is crucial for effective troubleshooting and ensuring your water heater operates safely and efficiently. Refer to your specific model’s diagram within the full manual for detailed component locations.
Model Number Identification & Manual Location
Locating your Ao Smith water heater’s model number is the first step towards accessing specific support and documentation. The model number is typically found on a label affixed to the unit’s exterior, often on the side or top panel. It’s a unique identifier crucial for ordering parts or finding the correct manual.
Ao Smith provides several avenues for accessing manuals. You can often find a digital copy on the Ao Smith website by entering your model number into their search tool. Alternatively, Lowes and other retailers may host manuals for models they sell.
Keep your model number readily available for future reference, as it streamlines any service or repair inquiries. A complete manual will contain detailed diagrams, safety information, and troubleshooting guides.
Safety Precautions & Warnings
Prioritize safety when installing, operating, and maintaining your Ao Smith water heater. Improper handling can lead to serious injury or property damage. Always disconnect both electrical and gas supplies before performing any service. Electric models pose a shock hazard; ensure the circuit breaker is off.
Gas models require careful attention to gas line connections to prevent leaks. Never attempt repairs if you are not qualified. The temperature and pressure relief (TPR) valve is a critical safety device – test it regularly as outlined in the manual.
Scalding can occur with hot water; set the thermostat to a safe temperature. Follow all instructions in the owner’s manual and heed all warning labels.

Installation & Setup
Proper installation is crucial for safe and efficient operation. This section details pre-installation checks, water and energy connections, and essential setup procedures.
Pre-Installation Checklist
Before beginning installation, ensure you have a comprehensive understanding of local plumbing and electrical codes. Verify the water heater’s voltage and gas type match your home’s supply.
Confirm adequate space around the unit for servicing and ventilation, referencing the owner’s manual for specific clearances. Gather necessary tools – pipe wrenches, screwdrivers, electrical testers, and Teflon tape.
Inspect the water supply lines for damage and ensure shut-off valves are accessible. For gas models, check the gas supply line for leaks using a soap solution. Crucially, have a qualified technician handle gas connections if you’re unsure. Finally, review the complete installation manual before proceeding to avoid potential issues.
Water Supply Connection
Begin by ensuring the main water supply to your home is completely shut off. Connect the hot and cold water lines to the designated inlets on the water heater, typically using dielectric unions to prevent corrosion.
Apply Teflon tape to all threaded connections to ensure a watertight seal. Tighten connections securely, but avoid over-tightening, which can damage the fittings.
Slowly open the main water supply valve and carefully inspect all connections for leaks; If leaks are detected, immediately shut off the water and re-tighten or re-apply Teflon tape as needed. Always flush the tank to remove debris before operating the heater.
Electrical Connection (Electric Models)
Before any electrical work, disconnect power at the main breaker panel! Identify the correct voltage and amperage requirements for your specific model, detailed in the manual. Connect the wiring according to local electrical codes, typically using appropriately sized wire and conduit.
Ensure a dedicated circuit is used, and the grounding wire is securely connected to the designated terminal. Double-check all connections for tightness and proper insulation.
Once wiring is complete, carefully restore power at the breaker panel. Verify proper operation and monitor for any unusual noises or smells. A tripped circuit breaker indicates a potential issue requiring immediate attention.
Gas Supply Connection (Gas Models)
Caution: Gas connections should only be performed by a qualified professional! Verify the gas supply matches the heater’s requirements (natural gas or propane); Use a new, approved gas connector and pipe dope specifically designed for gas lines.
Thoroughly check all connections for leaks using a soap and water solution – bubbles indicate a leak. Never use a flame to check for leaks! Ensure the gas shut-off valve is easily accessible.
Proper ventilation is crucial; confirm the heater is installed in a well-ventilated area. Pilot light issues require professional diagnosis and repair. Always follow local gas codes and manufacturer’s instructions.

Operation & Features
Explore your Ao Smith heater’s capabilities! Adjust the thermostat for desired temperatures, understand the control panel, and implement energy-saving practices for efficiency.

Thermostat Adjustment & Temperature Settings
Adjusting the thermostat on your Ao Smith water heater is crucial for comfort and energy conservation. Locate the thermostat dial, typically behind an access panel. Carefully turn the dial to your preferred temperature setting; 120°F (49°C) is generally recommended for household use, balancing comfort with energy efficiency.
Higher temperatures increase standby heat loss and potential scalding risks. Always allow ample time – usually 24 hours – for the water to reach the new set temperature. For electric models, a precise temperature setting is vital. Gas models may have a slightly wider temperature range. Regularly check the water temperature at a faucet to ensure it aligns with your thermostat setting, and consult the full manual for specific model instructions.
Understanding the Control Panel
Ao Smith water heater control panels vary by model, but common features include temperature displays, diagnostic lights, and mode selection buttons. Digital displays show the current water temperature, allowing for precise monitoring. Diagnostic lights indicate system status – power on, heating, or error codes.
Mode selection may offer options like “Vacation” to reduce energy consumption during extended absences. Some advanced models feature self-diagnostic capabilities, displaying error codes that pinpoint potential issues. Refer to your specific model’s manual for a detailed explanation of each control panel function. Understanding these controls empowers you to optimize performance and quickly identify potential problems, ensuring efficient operation.
Energy Saving Tips
Maximize efficiency with these Ao Smith water heater energy-saving tips. Lowering the thermostat to 120°F (49°C) reduces standby heat loss and saves energy. Insulate your hot water tank and pipes to minimize heat dissipation, especially in unheated areas. Utilize the “Vacation” mode when away for extended periods, significantly reducing energy consumption.
Regularly flush sediment from the tank to maintain heating efficiency. Consider a timer to schedule water heating during off-peak hours if your utility offers time-of-use rates. Repair any leaks promptly to avoid wasted water and energy. These simple adjustments can lead to substantial savings on your energy bills while prolonging your water heater’s lifespan.

Troubleshooting Common Issues
Diagnose problems quickly! This section details solutions for no hot water, leaks, tripped breakers, pilot light failures, and low water pressure – fix it now!
No Hot Water – Electric Models
Experiencing a lack of hot water from your electric Ao Smith water heater? Begin by verifying the circuit breaker hasn’t tripped; a common cause is simply a reset needed. Check the thermostat settings, ensuring they are appropriately adjusted for your desired temperature.
Inspect the high-limit reset button, often a small red button located near the upper thermostat – it may require a manual reset if triggered. If these steps don’t resolve the issue, a faulty heating element is a likely culprit.
Testing the elements with a multimeter can confirm functionality. Remember to disconnect power before any electrical inspection! Consult a qualified technician if you’re uncomfortable performing these checks, as electrical work can be dangerous;
No Hot Water – Gas Models
If your gas Ao Smith water heater isn’t producing hot water, first ensure the gas supply is active and the control valve is in the “On” position. Check the pilot light – if extinguished, follow the relighting instructions detailed in your owner’s manual. A faulty thermocouple is a frequent cause of pilot light issues, preventing gas flow.
Inspect the thermostat setting, confirming it’s set to the desired temperature. Consider a blocked flue vent, hindering proper combustion. If the burner ignites but no hot water results, a malfunctioning gas valve could be the problem.
Always prioritize safety; if you smell gas, evacuate and contact your gas company immediately. For complex issues, consult a qualified technician for diagnosis and repair.
Leaking Water Heater
A leaking Ao Smith water heater demands immediate attention. First, shut off the water supply to the unit to prevent further damage. Identify the leak’s source – connections, the tank itself, or the temperature and pressure (T&P) relief valve. Loose connections are often easily tightened, but tank leaks signify corrosion and potential failure.
If the T&P valve is leaking, it could indicate excessive pressure or temperature. Test the valve’s operation; if it continues to drip, replacement is necessary. Inspect the drain valve for leaks, tightening or replacing it as needed.
Never ignore a leak; prolonged water exposure can cause structural damage and mold growth. For tank leaks, professional replacement is generally required.
Tripped Circuit Breaker (Electric Models)
A frequently tripped circuit breaker is a common issue with electric Ao Smith water heaters. First, locate the breaker in your electrical panel and reset it. If it trips immediately again, do not continue resetting it – this indicates a problem. Potential causes include a short circuit within the heater, a faulty heating element, or an overloaded circuit.
Before investigating further, disconnect power to the water heater at the breaker. Carefully inspect the wiring for any signs of damage or burning. Testing the heating elements with a multimeter can identify a faulty component. If you’re uncomfortable with electrical work, contact a qualified electrician.
Remember, safety is paramount; always disconnect power before any inspection or repair.
Pilot Light Issues (Gas Models)
A consistently failing pilot light on your gas Ao Smith water heater requires careful attention. First, ensure the gas supply is turned on. If the pilot won’t light, follow the relighting instructions detailed in your owner’s manual – typically involving pressing and holding the pilot button while igniting the gas.
A dirty or faulty pilot assembly can also be the culprit. Inspect the pilot orifice for blockages and clean it gently with a wire. A failing thermocouple, which senses the pilot flame, will prevent the main burner from igniting. Replacing the thermocouple is often necessary.
If problems persist, do not attempt extensive repairs yourself; contact a qualified gas appliance technician.
Low Water Pressure & Flow Rate
Experiencing reduced water pressure or flow from your Ao Smith water heater can stem from several causes. First, verify that the water supply valve to the heater is fully open. Check for any closed or partially closed shut-off valves on the incoming water line.
Sediment buildup within the tank can restrict water flow; regular flushing (see the ‘Maintenance & Care’ section) is crucial. Ensure your home’s overall water pressure is within the recommended range (15-20 psi). A clogged aerator on your faucets can also mimic low pressure at the heater.
If the issue persists, inspect the dip tube inside the tank for damage or deterioration.

Maintenance & Care
Regular maintenance extends your Ao Smith heater’s life and efficiency. Flush sediment annually, inspect the anode rod, and test the temperature & pressure relief valve.
Sediment Flushing & Tank Cleaning
Sediment buildup is a common issue, reducing efficiency and potentially damaging your Ao Smith water heater. Annual flushing is crucial. First, turn off the power (electric) or gas supply. Connect a hose to the drain valve at the tank’s base and direct it to a suitable drain.
Open the drain valve slowly, allowing sediment to escape. Periodically open the cold water inlet valve briefly to stir up and flush out more sediment. Continue until the water runs clear.
Caution: Water may be hot! Close the drain valve, disconnect the hose, and restore the water and power/gas supply. Regular flushing prevents scale buildup, ensuring optimal performance and extending the lifespan of your water heater. A clean tank means efficient heating!
Anode Rod Inspection & Replacement

The anode rod is a sacrificial component designed to protect your tank from corrosion. Regular inspection – every three years is recommended – is vital. Turn off the power/gas and water supply. Locate the anode rod (usually under a hex head plug on top of the tank).
Carefully remove the rod. If it’s significantly corroded (less than 6 inches of core wire remaining), replace it with a new one. Applying pipe sealant to the threads before re-installation prevents leaks.
Important: A depleted anode rod means the tank itself will start to corrode. Replacing it proactively extends your water heater’s life and prevents costly leaks. This is a crucial maintenance step!
Temperature & Pressure Relief Valve Testing
Regular testing of the Temperature & Pressure (T&P) Relief Valve is a critical safety measure, ideally performed annually. Carefully lift and release the test lever on the valve. A burst of hot water should discharge through the drain pipe.
Caution: Water will be hot! Ensure the discharge pipe is directed safely. If the valve doesn’t release water, or if it drips afterward, it needs immediate replacement by a qualified plumber. A malfunctioning T&P valve can lead to dangerous pressure buildup.
Never cap or obstruct the discharge pipe. This valve prevents explosions. Proper function is essential for safe operation.

Advanced Troubleshooting & Repair
Expert repair requires understanding wiring diagrams, gas valve operation, and heating element replacement – tasks best handled by qualified technicians for safety.
Wiring Diagram Overview
Understanding the wiring diagram is crucial for advanced troubleshooting of electric Ao Smith water heaters. These diagrams illustrate the connections between components like the heating elements, thermostats, control board, and power supply.
Key elements to identify include the voltage (typically 240V), wire colors (often black, red, and white), and safety devices like the high-limit switch. Carefully trace the wiring paths to pinpoint potential faults, such as a broken wire or a faulty thermostat.
Always disconnect power before working with wiring. Diagrams vary by model, so refer to your specific unit’s documentation. Incorrect wiring can cause damage or create a safety hazard; professional assistance is recommended if you’re uncomfortable.
Gas Valve Troubleshooting
Diagnosing gas valve issues requires caution and a methodical approach. A malfunctioning valve can prevent ignition or cause inconsistent heating. First, verify the gas supply is active to the heater. Check for any visible damage to the valve or gas line.
Common problems include a faulty thermocouple, a clogged valve orifice, or a defective solenoid. Use a multimeter to test the solenoid for continuity. Never attempt to disassemble the valve yourself; it’s best left to qualified technicians.
Always prioritize safety – gas leaks are dangerous. If you smell gas, immediately shut off the supply and contact a professional. Refer to your model’s specific diagram for component locations.
Heating Element Replacement (Electric Models)
Replacing a heating element involves disconnecting power and draining the tank. Safety first: turn off the circuit breaker! Access the element by removing the access panel and insulation. Disconnect the wires connected to the element terminals.
Use a specialized wrench to unscrew the old element, being careful to avoid damaging the tank threads. Apply thread sealant to the new element’s threads before installation. Reconnect the wires, ensuring a secure connection.
Before restoring power, refill the tank completely to prevent element burnout. Test the new element with a multimeter for continuity. Consult your wiring diagram for correct connections.

Warranty Information & Support
Ao Smith offers robust warranties on its water heaters. For details, review your product’s specific warranty card or visit the Ao Smith customer support website for assistance.
Ao Smith Warranty Details
Ao Smith water heater warranties vary based on the model and tank type. Typically, residential tank water heaters come with a limited lifetime warranty on the tank, protecting against leaks due to defects. However, this often requires registration within 60 days of purchase.
Components, like heating elements or thermostats, usually have shorter warranty periods, often ranging from one to five years. Commercial models generally have reduced warranty coverage compared to residential units. It’s crucial to retain your proof of purchase and carefully review the warranty documentation included with your specific Ao Smith water heater.
Warranty coverage excludes issues caused by improper installation, misuse, sediment buildup, or lack of maintenance. Always follow the installation and maintenance guidelines outlined in the owner’s manual to maintain warranty validity.
Contacting Ao Smith Customer Support
Ao Smith provides multiple avenues for customer support. For immediate assistance, you can call their dedicated helpline at 1-800-662-7586. Their website, www.aosmith.com, offers a comprehensive FAQ section, downloadable manuals, and troubleshooting guides.
You can also submit inquiries through their online contact form, detailing your issue and providing your model number for faster service. Ao Smith maintains a network of authorized service centers for more complex repairs. To locate a service provider near you, use the “Find a Pro” tool on their website.
When contacting support, have your water heater’s model and serial number readily available. This information is essential for accurate assistance and warranty verification.











































































