What does the Viessmann Vitodens 050-W E373 fault code mean?
The E373 fault code on the Viessmann Vitodens 050-W indicates a problem with the system safety valve, which is crucial for maintaining safe operating pressure within the boiler. This fault can prevent the boiler from functioning properly and may pose safety risks if not addressed.
Common Causes
- Faulty Safety Valve: The safety valve may be stuck or malfunctioning, preventing it from opening and closing as needed.
- Pressure Issues: Incorrect system pressure, either too high or too low, can cause the safety valve to trigger the fault code.
Can I fix it myself? (DIY)
It is highly recommended to call a Gas Safe Engineer to address this issue, as it involves safety components of the boiler. Attempting to fix it yourself could lead to further complications or safety hazards.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the E373 fault code is approximately £150 to £250, depending on whether the safety valve needs to be replaced or simply serviced. This cost reflects the complexity of the repair and the need for a qualified technician.