What does the Viessmann Vitodens 111-W F72 fault code mean?
The F72 fault code on the Viessmann Vitodens 111-W indicates a problem with the domestic hot water (DHW) return temperature, suggesting that the temperature is not reaching the expected levels. This can lead to inadequate hot water supply and may require immediate attention to ensure proper functioning.
Common Causes
- Blocked Heat Exchanger: A blockage in the heat exchanger can prevent proper heat transfer, leading to incorrect return temperatures.
- Faulty Temperature Sensor: A malfunctioning temperature sensor may provide inaccurate readings, causing the system to misinterpret the return temperature.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it involves gas and electrical components that require professional handling. Attempting DIY repairs could pose safety risks.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F72 fault could range around £150 to £300, depending on whether the issue is a blocked heat exchanger or a faulty sensor. This includes parts and labour, with sensor replacements typically costing less than heat exchanger repairs.