What does the Viessmann Vitodens 111-W F73 fault code mean?
The F73 fault code indicates a problem with the heating circuit supply temperature, which may be too low or not reaching the required setpoint. This can lead to inadequate heating performance and may require immediate attention to ensure proper operation.
Common Causes
- Faulty Temperature Sensor: The temperature sensor may be malfunctioning, providing incorrect readings to the boiler control system.
- Circulation Issues: There could be a blockage or pump failure in the heating circuit, preventing hot water from circulating effectively.
Can I fix it myself? (DIY)
It is advisable to call a Gas Safe Engineer for any issues related to gas or electrical components. However, you can check the pressure gauge and ensure it is within the recommended range, typically between 1-1.5 bar, and reset the boiler if necessary.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F73 fault could range from £150 to £300, depending on whether a temperature sensor replacement or pump repair is needed. This estimate includes parts and labour costs typical for such repairs.