What does the Worcester Bosch Greenstar Ri F43 fault code mean?
The F43 fault code indicates a problem with the expansion vessel in the Worcester Bosch Greenstar Ri boiler. This typically means that the vessel is either faulty or has lost its charge, affecting the boiler’s ability to maintain proper pressure.
Common Causes
- Loss of Pressure: The expansion vessel may have lost its pre-charge pressure, leading to insufficient pressure regulation within the system.
- Physical Damage: The expansion vessel could be damaged or leaking, which would prevent it from functioning correctly.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as working with the boiler’s pressure system can be dangerous and requires professional expertise.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing the expansion vessel is around £200 to £300. This includes the cost of the part and labour, reflecting the complexity of the repair and the need for a qualified engineer.