What does the Worcester Bosch Greenstar CDi F22 fault code mean?
The F22 fault code indicates a dry fire condition or low water pressure within the boiler system. This typically means that the boiler is unable to operate safely due to insufficient water levels, which can lead to overheating and potential damage.
Common Causes
- Low Water Pressure: This can occur due to leaks in the system or insufficient water supply, leading to the boiler not having enough water to function properly.
- Air in the System: Trapped air can prevent water from circulating effectively, causing the boiler to detect a low water level.
Can I fix it myself? (DIY)
You can attempt to fix low water pressure by checking the pressure gauge and using the filling loop to add water to the system if necessary. However, if the issue persists or if you suspect a gas or electrical fault, it is crucial to call a Gas Safe Engineer for safety reasons.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F22 fault could range from £100 to £200, primarily for a pressure relief valve replacement or system re-pressurisation. This cost reflects the need for professional service and potential parts replacement.