AO Smith Tankless Water Heater Stuck in Standby Mode: How to Fix It

AO Smith is a reputable brand that produces high-quality tankless water heaters that are energy-efficient, reliable, and durable. However, like any appliance, they can encounter some problems over time. One of the most frustrating issues is when the tankless water heater gets stuck in standby mode and does not heat the water properly.

In this blog post, we will explain what causes an AO Smith tankless water heater to get stuck in standby mode and how to fix it. We will also answer some frequently asked questions about this topic.

What Causes an AO Smith Tankless Water Heater to Get Stuck in Standby Mode?

There are several reasons why an AO Smith tankless water heater may get stuck in standby mode. Some of them are:

Excessive use of hot water

A tankless water heater has a specific capacity and flow rate that indicates how much water it can heat at a given time. If you use too much hot water simultaneously, such as multiple showers or appliances, you may overload the heater and cause it to shut off or go into standby mode. The standby mode means that the heater will not heat the water at all until it is reset.

Temperature above the safety level

A tankless water heater has a safety mechanism called a thermal switch that protects the heater from overheating by cutting off the gas supply when the temperature reaches a certain limit.

If the temperature in your heater has reached the safety level, the thermal switch will activate and stop heating. As a result, your heater may go into standby mode and be unable to heat the water anymore.

Thermostat issues

A tankless water heater has a thermostat that controls the temperature of the water and signals the heater to turn on or off. If the thermostat is faulty or not calibrated properly, it may cause the heater to malfunction and go into standby mode. The thermostat may also be affected by external factors such as power surges, voltage fluctuations, or weather conditions.

Other problems

There may be other problems with your tankless water heater that can cause it to get stuck in standby mode, such as gas supply issues, venting system issues, water pressure issues, or internal component issues. These problems may require professional diagnosis and repair.

How to Fix an AO Smith Tankless Water Heater Stuck in Standby Mode?

Depending on the cause of the problem, there are different ways to fix an AO Smith tankless water heater stuck in standby mode. Some of them are:

Resetting the heater

If your tankless water heater is stuck in standby mode because of excessive use of hot water or temperature above the safety level, you can try to fix it by resetting it. To reset your heater, you need to turn off the power supply and press the reset button on the unit or on the remote control.

You should hear a click sound that indicates that your heater has been reset. Then you can turn on the power supply and check if the heater is working properly.

Adjusting the thermostat

If your tankless water heater is stuck in standby mode because of thermostat issues, you can try to fix it by adjusting the thermostat settings. You can use the remote control or the display panel on the unit to change the temperature setting or calibrate the thermostat. You should also check if there are any external factors that may affect the thermostat, such as power surges, voltage fluctuations, or weather conditions. You can also replace the thermostat if it is damaged or defective.

Conclusion

An AO Smith tankless water heater stuck in standby mode is a common problem that can have serious consequences if not addressed promptly. You should always inspect your heater for any signs of standby mode and take action to fix it as soon as possible. You should also follow the manufacturer’s instructions for installation and maintenance to ensure optimal performance and longevity of your heater.

FAQs

How do I know if my AO Smith tankless water heater is in standby mode?

You can tell if your AO Smith tankless water heater is in standby mode by looking at the display panel on the unit or on the remote control. If the display shows a “ST” symbol or a “Standby” message, it means that your heater is in standby mode and not heating the water.

How do I prevent my AO Smith tankless water heater from getting stuck in standby mode?

You can prevent your AO Smith tankless water heater from getting stuck in standby mode by following these tips:

Avoid using too much hot water simultaneously or reduce the demand for hot water by installing low-flow showerheads or faucets. Adjust the temperature setting of your heater to a lower level or use a mixing valve to blend cold water with hot water.

Maintain your heater regularly by flushing it with a descaling solution, replacing the filters and valves, inspecting the venting system, and checking the water pressure and flow rate.

Install a surge protector or a voltage regulator to protect your heater from power surges or voltage fluctuations. Use good quality water or install a water filter or a water softener to prevent corrosion or scale buildup.

How long does an AO Smith tankless water heater last?

An AO Smith tankless water heater can last up to 20 years or more if it is installed correctly and maintained regularly. However, the actual lifespan of a tankless water heater depends on several factors, such as the quality of the water, the frequency of use, the model and size of the heater, and the environmental conditions.

Does an AO Smith tankless water heater have a warranty?

Yes, every AO Smith tankless water heater comes with a warranty that covers certain defects and malfunctions for a specified period of time. You can contact the manufacturer or the authorized dealer to check if your heater is still under warranty and if you can get a free repair or replacement. You can also check the warranty documents online for more information.