What does the Vaillant ecoTEC plus F79 fault code mean?
The F79 fault code on a Vaillant ecoTEC plus boiler indicates a problem with the system features, often related to the boiler’s internal components or communication issues. This fault can prevent the boiler from operating correctly, leading to heating or hot water supply interruptions.
Common Causes
- Faulty PCB: The printed circuit board may have developed a fault, disrupting communication between components.
- Sensor Issues: Malfunctioning sensors, such as the temperature or pressure sensors, can trigger the F79 fault code.
Can I fix it myself? (DIY)
It is highly recommended to call a Gas Safe Engineer to diagnose and repair the F79 fault, as it may involve complex electrical and gas components that require professional expertise.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for the F79 fault could range from £150 to £300, depending on whether the issue is with the PCB or sensors, as replacement parts and labour can vary significantly.