What does the Viessmann Vitodens 200-W F31 fault code mean?
The F31 fault code on the Viessmann Vitodens 200-W indicates a malfunction in the flow temperature sensor. This sensor is crucial for monitoring the temperature of the water flowing through the heating system, and its failure can disrupt the boiler’s operation.
Common Causes
- Sensor Failure: The flow temperature sensor may be defective or damaged, leading to inaccurate readings.
- Wiring Issues: Damaged or loose wiring connections to the sensor can cause communication failures, triggering the fault code.
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 repair it yourself could lead to further complications.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing the flow temperature sensor is around £150 to £200. This includes the cost of the part and labour, reflecting the complexity of the repair and the expertise required.