VIESSMANN VITODENS 200-w: Resolving Error F4 - Damaged Burner Automatic (Replacement & Repair)

Hello forum members. I have a boiler as in the subject, so the F4 fault has appeared for some time. It shows me as damaged BURNER AUTOMATIC. And the question is which element it is and whether it can be repaired or replaced with a new one. I attach a photo. Thank you in advance.

The burner control unit is the boiler automatics (electronic main board) which costs about PLN 1,500.

Is that the only possibility? Because I wonder that the boiler works after the reset, the error is displayed after a few days, and when it is cold, it works for up to two weeks. It seems to me that when it is turned on often, nothing happens to it.

Unscrew the ionization electrode (detail C in the photo) and clean its metal part.
Perhaps it would be worth calling the service for the annual technical inspection.

The technical inspection was five months ago. I'll clean the electrode and let me know. Thanks

Hello
This fault is most likely caused by the wear of the ionization electrode.
this element is responsible for flame control and optimal combustion - unfortunately it is immersed in the flame and wears out due to slow burnout, losing its properties. This vulnerability will only get worse
The gas fittings dosing gas into the combustion chamber or the unsealing of the flue gas conduit may also be responsible for this error.
I suggest calling a service that will visually check the electrode, check the level of the so-called ionization current and performs exhaust gas analysis to verify the correctness of the combustion process. Cleaning the electrode may only help temporarily or not at all.
Most likely, the ionization electrode will be replaced and, depending on the type of boiler and the year of construction, the so-called code plug.
greetings

Can you explain why this coding plug is replaced?

Yesterday I cleaned the ionization electrode and the whole electrode block. It works for now.

The coding plug is actually a small chip on which important information is stored about the type of boiler, parameterization of the combustion process in which the ionization electrode is actively involved, read by the automation.
According to my information, at the moment Viessmann makes electrodes made of two metals, and thus, there will be different values of the ionization current, which are stored in this chip.
Replacing the ionization electrode with a new one and leaving the old plug on may not really eliminate the problem.
But this will be judged by the service technician by looking at the serial number of the device and the software number on the plug in the automation,

The electrode is one of the causes that can cause F4. When the errors you wrote appear, you should first check many things, the gasket, the chimney system, perform manual calibration, maybe reset the plug or maybe a master reset, check the electrical connections, perform gas measurements, perform exhaust gas analysis and some other important things that you do not need to do yourself. measuring devices you are not checking for yourself.
greetings

Thank you very much for your comprehensive answers. After cleaning everything works (: