What does the Viessmann Vitodens 050-W E342 fault code mean?
The E342 fault code on the Viessmann Vitodens 050-W indicates a problem with the system flow sensor, which is responsible for monitoring the flow of water through the heating system. This fault can lead to inefficient heating and may cause the boiler to shut down to prevent damage.
Common Causes
- Blocked Flow Sensor: Debris or scale buildup can obstruct the flow sensor, preventing it from accurately measuring water flow.
- Faulty Flow Sensor: The flow sensor itself may be malfunctioning due to wear and tear or electrical issues, leading to incorrect readings.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer to diagnose and repair the issue, as working with gas appliances can be dangerous and requires professional expertise.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing a faulty flow sensor on a Viessmann Vitodens 050-W is around £150 to £250. This includes the cost of the part and labour, as flow sensors typically range from £50 to £100, and professional installation is necessary for safety and compliance.