What does the Baxi Megaflo E790 fault code mean?
The E790 fault code on the Baxi Megaflo indicates a performance issue with the domestic hot water (DHW) system. This typically suggests that the boiler is unable to deliver hot water at the expected temperature or flow rate.
Common Causes
- Blocked Heat Exchanger: A buildup of limescale or debris can restrict water flow, affecting the heating efficiency.
- Faulty Temperature Sensor: If the temperature sensor is malfunctioning, it may not accurately detect the water temperature, leading to performance issues.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for any repairs related to gas or electrical components. However, you can check the pressure gauge and ensure it is within the normal range (1-1.5 bar) and reset the boiler if necessary.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the E790 fault could range from £150 to £300, depending on whether the issue is a blocked heat exchanger or a faulty temperature sensor, which may require part replacement and labour.