What does the Viessmann Vitodens 111-W F59 fault code mean?
The F59 fault code on the Viessmann Vitodens 111-W indicates a malfunction in the heating circuit thermostat. This can lead to issues with temperature regulation in the heating system, affecting overall performance.
Common Causes
- Faulty Thermostat: The thermostat may be defective or malfunctioning, preventing it from accurately reading or controlling the temperature.
- Wiring Issues: Damaged or loose wiring connections to the thermostat can disrupt communication between the thermostat and the boiler.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer to diagnose and repair this issue, as it involves gas and electrical components that require professional expertise.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F59 fault code is around £150 to £250. This includes the cost of replacing the thermostat and any necessary labour charges.