What does the Vaillant ecoTEC pro F87 fault code mean?
The F87 fault code on a Vaillant ecoTEC pro boiler indicates a problem with the system’s replacement components, which may include issues with the heat exchanger or other internal parts. This fault typically requires professional diagnosis and repair to ensure safe and efficient operation.
Common Causes
- Faulty Heat Exchanger: A malfunctioning heat exchanger can lead to improper heating and trigger the F87 fault code.
- Incorrect System Pressure: Low or high system pressure can affect the boiler’s performance and may cause this fault to appear.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for any issues related to gas or electrical components. Attempting to fix these problems without proper training can be dangerous.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F87 fault may range from £150 to £300, depending on whether the heat exchanger needs replacement or if adjustments to the system pressure are required. This estimate reflects the cost of parts and labour for a qualified engineer.