What does the Worcester Bosch Greenstar CDi F74 fault code mean?
The F74 fault code indicates an issue with voltage regulation within the boiler’s electrical system. This can lead to improper functioning of the boiler, affecting its ability to heat water efficiently.
Common Causes
- Power Supply Issues: Fluctuations or interruptions in the electrical supply can cause the boiler to display the F74 fault code.
- Faulty PCB (Printed Circuit Board): A malfunctioning PCB may not regulate voltage correctly, leading to this fault code being triggered.
Can I fix it myself? (DIY)
It is strongly advised to call a Gas Safe Engineer for this issue, as it involves electrical components that can be dangerous if handled improperly. Attempting DIY repairs could void your warranty or lead to further damage.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F74 fault code is around £200 to £300. This includes potential replacement of the PCB and associated labour costs, which are necessary for ensuring safe and effective operation of the boiler.