What does the Viessmann Vitodens 111-W F24 fault code mean?
The F24 fault code on the Viessmann Vitodens 111-W indicates an overheating issue within the boiler system. This typically occurs when the temperature of the water exceeds safe operating limits, potentially leading to system damage if not addressed promptly.
Common Causes
- Blocked Heat Exchanger: A buildup of debris or limescale can restrict water flow, causing the boiler to overheat.
- Faulty Temperature Sensor: If the temperature sensor is malfunctioning, it may not accurately read the water temperature, leading to overheating.
Can I fix it myself? (DIY)
While some issues may be resolved by checking and clearing any blockages, it is strongly advised to call a Gas Safe Engineer for any gas or electrical-related problems to ensure safety and compliance with regulations.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F24 fault could range from £150 to £300, depending on whether the issue is a blocked heat exchanger or a faulty temperature sensor. This includes parts and labour, as both components may require professional servicing.