Learn More About AO Smith Tankless Water Heater Troubleshooting

What happens if the hot water faucet only produces cold water when you try to use it? There’s always a chance that your water heater won’t function when you want a hot shower. It is unpleasant because you can’t immediately access the internet!

Having an odd water heater code flash in your face is inconvenient. Although AO Smith tankless water heater troubleshooting may be challenging, we can assist you.

AO Smith Tankless Water Heater Troubleshooting

A big advantage of AO Smith tankless water heaters with remote controls is that they contain a self-diagnosing feature that helps identify heating issues.

The fitted remote control will produce a sound, and an error code will appear on the screen if there is a problem with the water heater.

ao smith tankless water heater troubleshooting

Some versions, including the 240, 340, and 540 series, include remote controllers that may show these codes. Similarly, the temperature will be replaced with an error code on the appliance’s LED display.

However, an LCD device like the 510 series will display an error code notice. Others, like the 110 and 310, feature a red light that blinks quickly on the device.

The LED blinks more frequently when an AO Smith tankless water heater troubleshooting occurs. It is preferable to consult your owner’s handbook to find out what model you have and where the error number is.

A common step in troubleshooting AO Smith tankless water heater is to turn on the hot water tap and observe the unit’s response. This can help diagnose issues related to water flow, temperature consistency, or heating elements.

AO Smith Tankless Water Heater Error Codes

  1. AO Smith Water Heater Error Code E02

The AO Smith Electric Tankless Water Heater’s error code “E02” denotes that the heater has determined that the heated water has reached too high. The AO Smith also has a high-limit switch or electric-cut-off button, similar to other electric water heaters.

  1. AO Smith Water Heater Error Code E03

If insufficient water is in the heater, the error signal “E03” will flash on your AO Smith water heater. Your water heater may display this unpredictable code if there is air in the waterline. Sometimes this problem is brought on by a bad sensor.

  1. AO Smith Water Heater Error Code E04

When it senses AO Smith tankless water heater problems or a leak in the heater, your AO Smith water heater will display the fault code “E04”. A water heater can leak from the top, bottom, and sides, among other areas. The leak sensor detects water leaking from the water heater at any location and alerts you by flashing the error signal “E04.”

  1. AO Smith Electric Water Heater Error Code E06

The too-hot water temperature error number on your AO Smith water heater is “E06.” In other words, the sensor will display this error code if it determines that the water temperature is too high.

The main causes of an excessively high water temperature in your heater are:

  • Often a broken thermostat.
  • A shortened heating element.
  • A thermostat that is not fitted properly to the tank.
  1. AO Smith Electric Water Heater Error Code E10-E13

E10, E11, E12, and E13 error codes are produced by either an open thermistor or an open intake temperature sensor on your AO Smith electric water heater. Those AO Smith tankless water heater codes will appear for both 2-chamber and 4-chamber versions.

  1. AO Smith Electric Water Heater Error Code E14

The 4-chamber model of the AO Smith Electric Tankless Water Heater only generates this error code. If the outlet thermistor (TH-4) is left open, the water heater often shows this error number.

  1. AO Smith Electric Water Heater Error Code E20-E24

The fault codes E20, E21, E22, E23, and E24 are only present in 2-chamber and 4-chamber models of AO Smith water heaters for a single cause. The thermistor electrically shorts out as a result.

  1. AO Smith Electric Water Heater Error Code E51 & E52

If your AO Smith Electric Tankless Water Heater displays error codes E51 or E52, you should know that the control board and user interface have lost contact.

Final Thought

With your newfound knowledge about AO Smith Tankless Water Heater Troubleshooting, you can start taking care of any problems yourself.

Regular maintenance is key to preventing many common issues with tankless water heaters. This includes checking for mineral buildup, ensuring proper venting, and periodically inspecting electrical connections. By staying proactive, you can extend the lifespan of your unit and ensure it operates efficiently.

If you’re experiencing error codes or the unit fails to heat water adequately, refer to the AO Smith manual for specific troubleshooting guidance. Each error code can pinpoint a particular issue, from gas supply problems to internal system errors, providing a clear path for resolution.

Just remember to speak with a service professional if you have any questions. Safety is of the highest importance when it comes to gas and electricity.

Gravatar Image
Heater Technician is a skilled author and water heater expert with years of experience in the field. He has authored several articles and books on various aspects of water heater installation, maintenance, and repair.