A.O. Smith Error Code 391: If you have an A.O. Smith Hot Water System and see Error Code 391 flashing twice on the display screen, it means there is a problem with the air-fuel ratio rod (AFR) of your water heater. The AFR rod is responsible for monitoring the air fuel ratio of the water heater’s internal combustion engine, which is very important for its proper functioning. However, the AFR rod can get damaged or covered in soot, which can prevent it from working correctly. It is crucial to keep the AFR rod clean and in good condition to ensure the safe use of your water heater. You should clean the rod to remove any soot and check for any damage or loose connections. In some cases, cleaning the sensors may solve the issue, but in other cases, you may need to replace the AFR rod as soon as possible
A.O. Smith Hot Water – Error Code 391
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A.O. Smith Hot Water System – Error Code 391
Is your A.O. Smith hot water system showing up with Error Code 391 on the screen? In this article, we’ll look at why it is happening, some potential next steps for fixing error code 391 and whether you should keep using your A.O. Smith hot water system.
What is a A.O. Smith Error Code 391?
If you have an A.O. Smith Hot Water System and see Error Code 391 flashing twice on the display screen, it means there is a problem with the air-fuel ratio rod (AFR) of your water heater. The AFR rod is responsible for monitoring the air fuel ratio of the water heater’s internal combustion engine, which is very important for its proper functioning. However, the AFR rod can get damaged or covered in soot, which can prevent it from working correctly. It is crucial to keep the AFR rod clean and in good condition to ensure the safe use of your water heater. You should clean the rod to remove any soot and check for any damage or loose connections. In some cases, cleaning the sensors may solve the issue, but in other cases, you may need to replace the AFR rod as soon as possible
Recommended solution/fix steps
If you see Error Code 391 on your A.O. Smith Hot Water System, the first step is to clean the air-fuel ratio rod (AFR) of any soot. This can be done by gently wiping it with a soft cloth or brush. Next, check for any damage or loose connections on the AFR rod. If there is damage or a loose connection, you may need to find a replacement AFR rod. It is important to keep the AFR rod in good condition to ensure the safe operation of your water heater. If cleaning and checking for damage does not resolve the issue, it is recommended to contact a professional or the manufacturer for further assistance
Fault codes that are often associated with or mistaken for error code 391 are: Error Code: 391, Error Code: 3g1, Error Code: 39l, Error Code: 3B1, Error Code: 3gI, Error Code: 39I, Error Code: 3Bl, Error Code: 3BI, Error Code: 3gI, Error Code: 3B1
Can I still use my A.O. Smith hot water system?
After seeing Error Code 391 on the A.O. Smith Hot Water System, the machine can still be operated, but it requires attention. This error code indicates a problem with the water heater’s air-fuel ratio rod (AFR). The AFR rod is responsible for monitoring the air fuel ratio of the water heater’s internal combustion engine, which is crucial for its proper functioning. However, damage and soot can hinder the AFR rod’s performance. To continue using the water heater safely, it is important to clean the AFR rod of any soot and check for any damage or loose connections. In some cases, simply removing the soot may solve the issue, but in other cases, a replacement AFR rod may be necessary
