Hermann Boiler Error F20

What could this error affecting Hermann boilers mean?

Hermann boilers can be found in many homes because they are reliable and very efficient. But like any appliance, they are not exempt from having problems, especially if they have not been properly maintained.

The F20 error code in Hermann boilers indicates that the boiler has experienced a safety shutdown and has turned off due to an overheating fault. In this article, we will explore the possible causes behind this code and provide you with appropriate solutions to resolve it.

This problem can be due to various factors, including false positives generated by faulty temperature sensors. Let's see what causes this problem:

• Damaged sensors that may be sending false positive alerts: The sensor that measures the temperature of the inlet water may be failing, as well as the sensor that monitors the temperature of the return water.
• Internal wiring of the boiler in poor condition or disconnected: This wiring may have been damaged by high temperatures or disconnected, so it needs to be thoroughly checked, as well as its connections.
• Overheating due to obstruction in the exhaust gas outlet: Boilers are often turned off in summer, and when you want to use them in winter, the outlet may be blocked by dust, cobwebs, nests, and/or dirt, and you may not have noticed.
• Fault in the boiler's electronic PCB board: It is possible that a component of the board controlling all the sensors and parts of your boiler has been damaged and is not functioning correctly.

Now that you know the causes of this fault in your boiler, let's see what the solutions are so you can fix it and continue using it.

How can the F20 error code be fixed in the Hermann boiler?

These are the solutions you can apply to fix this issue with your Hermann boiler. Do not skip any step and read everything carefully so you can resolve this fault in the best possible way:

1. An effective solution to fix technical faults is to reset the devices, and this also applies to boilers: This procedure is very basic, accessible, and recommended. To do this, turn off the boiler completely and disconnect it from the electrical supply momentarily. We suggest leaving it disconnected for at least fifteen minutes before restoring the connection. Once this is done, reconnect and activate the boiler again to check if the fault has been corrected. If the problem persists, you will need to proceed with the other steps we have outlined below.
2. Check the temperature sensors of your Hermann boiler: Verify that the temperature sensors, both inlet and return, are in good condition. If you know how to use a multimeter, then it would be good to use it to check if the water inlet sensor is working properly, as well as the return water sensor. It is possible that your boiler does not have a real overheating problem, but rather the temperature sensors are damaged and are throwing error codes as false positives.
3. Inspect all the internal wiring of your Hermann boiler: Inspect Connections and Cables: It may be that due to high temperatures, the cable insulation has given way and has ended up melting or burning them. So, you have to make sure that all the internal wiring of your boiler is in perfect condition. Also, take the opportunity to check the connections and the ends of all these cables, especially those that control the ignition of the boiler. In the summer months when you use your boiler very little or simply have not used it at all, rodents may chew on the cables to sharpen their teeth. Check that the cables are not cut, burned, scorched by moisture, or loose and disconnected. If you find abnormalities in the wiring, make the necessary repairs and check if the fault in your boiler has been resolved.
4. Check that the boiler does not have any type of obstruction in the exhaust gas duct: If summer has passed, you are in winter, and you have not used the boiler until now, then you have to make sure that this duct is completely free and clean. It often happens that birds nest in the outlet of this duct and/or rodents or any other animal is living there. It can also happen that the duct is blocked by dust from the environment, tree leaves, cobwebs, etc. Perform preventive maintenance on this duct before reactivating your boiler in winter. Make sure this duct is free and clear so that the gases do not accumulate and you do not have an excess of temperature in the boiler, causing error codes like F20.
5. Check the electronic PCB board of your boiler with a multimeter: If you have already checked everything above and the problem continues, then probably some component of the boiler's electronic board is defective and needs to be replaced. If you have knowledge in electronics, you can try to repair it yourself using the appropriate tools, such as a multimeter to first detect which components are damaged and a soldering iron and heat gun to remove these components and replace them with new ones. If you notice that the problem could become very complicated, perhaps it would be best to replace the electronic board completely.
6. If you continue to face difficulties with your boiler, it is important to thoroughly review each of the steps we have indicated: The most important thing is not to get discouraged and read carefully and attention to detail everything we have described. Make sure you have not overlooked any recommendations from our list of tips. If the problem persists despite your efforts, then it is time to seek professional advice. A qualified technician or the official Hermann technical support are trained to identify and remedy your boiler without any problem.
7. If the problem persists, the key to an effective solution lies in the expertise of boiler specialists: Whether it's a qualified technician or the Hermann technical support team, they are equipped to restore the operation of your heating system. They are available for contact by phone, so give them a call and arrange a home visit to give your boiler a definitive solution. You don't have to spend winter times feeling cold, so you can trust the professionals to restore the operation of your boiler.

In conclusion, we know for certain that the F20 error code in Hermann boilers is related to an overheating problem in the appliance. Check the temperature sensors to avoid false positives, the connections of the internal wiring of the boiler, and the combustion gas outlet to make sure they do not accumulate inside the boiler generating an excess of temperature. If you cannot find the solution, trust the Hermann experts to resolve this inconvenience.

We hope we have been very helpful today in fixing this problem you had with your boiler. Remember that always at the end of summer and the beginning of winter, you have to perform preventive maintenance on your boiler to ensure its optimal operation and avoid this type of uncomfortable situations. Good luck!