My two years old Vaillant Turbomax boiler is constantly showing a fault code i.e. F28. In order to get rid it of, I have turned off the boiler. After 1 or 2 hour, I switched it on but again the same issue. Someone please tell the ways of addressing this issue.
This problem is quite common in majority of the Vaillant Turbomax & usually caused by the faulty ignition. For fixing it, firstly, check the ignition’s leads current condition like is the spark being produced. In case not, you have to replace them as it might fix the issue. If you notice the spark, do check the power, which is going to the gas control device. Afterwards, check if the gas is easily flowing through. In case, gas valve has the power but the gas is not flowing, it might need replacement.