What does the Worcester Bosch Greenstar i F42 fault code mean?
The F42 fault code indicates a problem with the hot water sensor in the Worcester Bosch Greenstar i boiler. This sensor is responsible for monitoring the temperature of the hot water, and a fault can lead to inadequate heating or hot water supply.
Common Causes
- Faulty Hot Water Sensor: The sensor may be malfunctioning or damaged, leading to incorrect temperature readings.
- Wiring Issues: Damaged or loose wiring connections to the sensor can disrupt its functionality and cause the fault code to appear.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it involves electrical components and safety risks. Attempting to fix it yourself could lead to further damage or safety hazards.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing the hot water sensor is around £150 to £200. This includes the cost of the part and labour, reflecting the complexity of the repair and the need for a qualified engineer.