What does the Viessmann Vitodens 111-W F26 fault code mean?
The F26 fault code indicates a malfunction in the flow sensor of the Viessmann Vitodens 111-W boiler. This sensor is crucial for measuring the flow of water through the system, and its failure can lead to heating issues or system shutdown.
Common Causes
- Blocked Flow Sensor: Debris or limescale buildup can obstruct the flow sensor, preventing accurate readings.
- Electrical Fault: Issues with the wiring or connections to the flow sensor can disrupt its functionality, leading to erroneous fault codes.
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. Attempting to fix electrical or gas-related components without proper training can lead to safety hazards.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing a faulty flow sensor on a Viessmann Vitodens 111-W is around £150 to £250. This includes the cost of the part and labour, as flow sensors typically range from £50 to £100, with additional charges for professional installation.