What does the Viessmann Vitodens 050-W E266 fault code mean?
The E266 fault code on the Viessmann Vitodens 050-W indicates a malfunction in the domestic hot water (DHW) pump. This issue can prevent the system from effectively circulating hot water, leading to inadequate hot water supply.
Common Causes
- Blocked Pump: Debris or scale buildup can obstruct the pump, preventing it from functioning properly.
- Electrical Fault: Issues with the pump’s electrical connections or the control board can lead to a failure in pump operation.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it involves electrical components and potential safety hazards. Attempting to fix it yourself may void warranties or lead to further complications.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing a faulty DHW pump on a Viessmann Vitodens 050-W is around £300. This includes parts and labour, as the pump itself typically costs around £150-£200, with the remainder covering the engineer’s time.