What does the Vaillant ecoTEC pro F43 fault code mean?
The F43 fault code on a Vaillant ecoTEC pro indicates a malfunction with the water temperature sensor. This issue can prevent the boiler from operating efficiently, leading to heating and hot water supply problems.
Common Causes
- Faulty Temperature Sensor: The sensor may be damaged or malfunctioning, causing incorrect temperature readings.
- Wiring Issues: Damaged or loose wiring connections to the sensor can disrupt its functionality and lead to the fault code.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer to diagnose and repair this issue, as it involves electrical components and gas safety regulations. Attempting DIY repairs could be dangerous.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing a faulty water temperature sensor on a Vaillant ecoTEC pro is around £150 to £200. This includes the cost of the part and labour, reflecting the complexity of the repair and the need for a qualified technician.