A.O. Smith Tankless Water Heater Troubleshooting

AO Smith Tankless Water Heater Troubleshooting: Steps-by-Step Guide

  • AO Smith tankless water heater troubleshooting is definitely a necessary procedure for solving your AO Smith tankless water heater problems. Apart from having your fireplace and your heaters installed in your residence, having a tankless water heater that guarantees a continuous hot water supply is an under-estimated coping mechanism for winter. During winter and other cold seasons, I want to walk up to my faucets and be greeted with instantaneous and ever-flowing warmth. 
  • Many tankless water heater brands exist, and just like several other tankless water heaters, A. O. Smith offers a complete line of natural gas and liquid propane tankless water heaters for continuous hot water needs. The A.O Smith ATO-510-P is a vivid example.  But you may want to know what happens when your water heater begins to perform below par, a quick step for detecting and fixing faults, especially in home appliances, is called troubleshooting. Hence, this article takes you through the A.O. Smith water heater manual to provide the necessary tips for troubleshooting your water heater.

A.O. Smith Water Heater Warranty

Generally, AO Smith tankless water heaters are guaranteed for five years on tank failure and one year for the failure of any of its parts. Hence, if you discover a leaking tank within five years of usage, you. Or, if any other part of the machine is faulty within the first year of purchase, you can always contact your local distributor for further follow-up. 

However, before replacing or repairing your products, you must satisfy your local distributor or the brand manufacturer that the unit has been handled according to the general warranty conditions. These general conditions are contained in the a.o. smith water heater manual.

A.O. Smith tankless water heater troubleshooting

A.O. Smith tankless water heaters are known for their efficiency. Indeed, they are one of the most reliable water heater brands. However, like any appliance, they may encounter occasional issues. A.O. Smith tankless water heater troubleshooting refers to identifying potential problems that may arise with these units. By understanding the troubleshooting steps, users can diagnose and resolve issues.  Only then can one guarantee a continuous hot water supply and maximize the heater’s lifespan. Let’s explore common troubleshooting techniques to keep your A.O. Smith tankless water heater running smoothly.

What to Do When A.O. Smith Water Heater is Not Heating?

The entire purpose of a water heater is defeated when it does not supply hot water, is it not? If your A.O. Smith water heater is not heating, there are a few troubleshooting steps you can take to try to solve the problem. First, check to ensure that the power to the unit is turned on. Also, ensure the circuit breaker or fuse has not been tripped. If the power is on, but the water is still not heating, try the following troubleshooting steps; 

  • Check the power supply and ensure it’s connected. 
  • Confirm gas supply (for gas models) and pilot flame. 
  • Inspect electrical components for faults. 
  • Clean or replace clogged air intake/exhaust vents. 
  • Verify thermostat settings and adjust if needed. 
  • Flush the system to remove mineral buildup. 
  • Test for ignition problems and address any issues. 
  • Contact A.O. Smith support if problems persist. 
  • Follow the manufacturer’s guidelines for safety and maintenance.

Fixing Tankless Water Heater Fluctuating Temperature

It can be frustrating when your tankless water heater can not maintain a steady temperature. When this happens, the tankless water heater goes cold after a few minutes of turning it on. The major cause of this problem is usually a blocked filter. When the filter is blocked, water movement is hindered, hence disrupting the appliance’s performance. In other cases, a faulty thermostat or temperature sensor may need replacement. Read below to fix it

Clean the Filter

Turn off the water supply to clean the filter and power the unit, then locate the filter, usually near the inlet, and remove it. Rinse the filter under running water to remove debris and sediment. Soak it in vinegar for a few hours if it is heavily clogged. Finally, reinstall the filter, ensuring it fits securely, and restore the water and power supply to the heater. This remedy applies to both electric and AO Smith gas water heater.

Adjust the Temperature Setting

If the temperature setting is not a problem, adjust the unit’s temperature setting. Consult the owner’s manual for instructions on how to do this.

Replace the Thermostat or Temperature Sensor

The thermostat or temperature sensor may malfunction if the temperature setting and filter are not the issues. Consult a professional to diagnose and replace these components if necessary. Finally, learning your AO Smith water heater error codes can not be emphasized enough.

The Conclusion: AO Smith tankless water heater troubleshooting

In a nutshell, troubleshooting your A.O. Smith is the first line of action when you discover an anomaly in its functioning. Troubleshooting is the process of investigating faults and their possible causes in an attempt to proffer a lasting solution. When the procedure is followed properly, you may become your own repairman. 


What causes my tankless water heater to leak?

A leaking tankless water heater can present a serious problem that requires immediate attention. A few fundamental factors explain this condition. Continuous use may have disconnected a connection or attachment. These pieces may become looser with time, resulting in spillage. Conversely, the water pipe may require replacement if it is broken or deteriorated.

How do I fix a leaking tankless water heater?

The first thing to do is, take some safety precautions and turn off the unit’s power supply. The next thing to turn off is your water supply. Go on to inspect the surrounding of the unit for visible signs of damage. Tighten or loosen connections and fittings that you find. If you discover that the water line is corrupted, please contact a professional to fix it. Lastly, check for condensation.

How do tankless water heaters reduce energy bills?

Tankless water heaters save energy by removing the standby heat loss typical tank water heaters face. They simply heat water as needed, eliminating the continual energy usage of maintaining a big hot water tank. This on-demand heating approach saves energy waste and utility expenses, potentially saving money on energy bills.

How do I get the warranty on an A.O Smith water heater?

Register your product on the A.O. Smith website or complete the warranty registration card with the unit to get the warranty on an A.O. Smith water heater. Provide the required information, including the purchase date and model number. This will activate your warranty and ensure coverage for the specified period.

How do I keep my tankless water heater performing at its best?

Follow these tips to get the most out of your tankless water heater. Clean or flush the device regularly to eliminate mineral accumulation according to the manufacturer’s instructions. If required, inspect and replace the water filter. Maintain the heater’s water pressure and flow. Check for gas leaks (if any) and make sure the gas supply is steady. Maintain proper ventilation and keep the surrounding area clear of debris. Finally, arrange regular expert maintenance to identify and fix potential concerns immediately, ensuring your tankless water heater runs effectively and dependably. You may also install a recirculating pump for a better hot water supply throughout your faucets.


How long is an A.O. Smith tankless water heater tank guaranteed for?

  1. Seven years
  2. Four years
  3. One year 
  4. Five years