What does the Viessmann Vitodens 050-W E346 fault code mean?
The E346 fault code indicates a problem with the domestic hot water (DHW) sensor in the Viessmann Vitodens 050-W boiler. This typically means that the sensor is either faulty or not providing accurate temperature readings, which can affect the boiler’s ability to heat water effectively.
Common Causes
- Faulty DHW Sensor: The sensor may have failed due to wear and tear or manufacturing defects, leading to incorrect readings.
- Wiring Issues: Damaged or loose wiring connections to the DHW sensor can disrupt communication between the sensor and the boiler’s control unit.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it involves electrical components and safety risks. Attempting to fix it yourself could void warranties or lead to further complications.
Estimated Repair Cost (2026 UK Prices)
The estimated cost for replacing the DHW sensor is around £150 to £200, including parts and labour. This is based on the average cost of the sensor and the typical hourly rate for a Gas Safe Engineer in the UK.