What does the Worcester Bosch Greenstar CDi F43 fault code mean?
The F43 fault code on the Worcester Bosch Greenstar CDi indicates a problem with the diverter valve, which is responsible for directing hot water to either the heating system or the hot water taps. When this valve fails, it can lead to issues such as no hot water or heating, requiring attention.
Common Causes
- Mechanical Failure: The diverter valve may become stuck or fail due to wear and tear, preventing it from operating correctly.
- Electrical Issues: Faulty wiring or a malfunctioning actuator can disrupt the signal to the diverter valve, causing it to fail to switch between heating and hot water.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as working on gas appliances can be dangerous and requires professional expertise. Attempting to fix the diverter valve without proper training may lead to further complications.
Estimated Repair Cost (2026 UK Prices)
The estimated cost for repairing or replacing the diverter valve on a Worcester Bosch Greenstar CDi is approximately £250 to £350. This includes parts and labour, as diverter valves can be complex components requiring skilled installation.