What does the Baxi 600 Series E520 fault code mean?
The E520 fault code on the Baxi 600 Series indicates a problem with the domestic hot water (DHW) chamber temperature, suggesting that the temperature is either too high or too low. This can lead to inadequate hot water supply or potential overheating issues.
Common Causes
- Faulty DHW Sensor: The temperature sensor may be malfunctioning, providing incorrect readings to the boiler’s control system.
- Blocked Heat Exchanger: A blockage in the heat exchanger can prevent proper heat transfer, affecting the DHW temperature.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer to diagnose and repair this issue, as it involves gas and electrical components that require professional expertise.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for the E520 fault could be around £150 to £250, primarily due to the potential need for a new DHW sensor or cleaning of the heat exchanger, which involves labour and parts.