How to fix Baxi Platinum fault code F48

What does the Baxi Platinum F48 fault code mean?

The F48 fault code on a Baxi Platinum boiler indicates a fault with the domestic hot water (DHW) heat exchanger. This issue can lead to inadequate hot water supply and may require immediate attention to restore proper functionality.

Common Causes

  • Blocked Heat Exchanger: Debris or limescale buildup can obstruct the heat exchanger, preventing efficient heat transfer.
  • Faulty Temperature Sensor: A malfunctioning temperature sensor may incorrectly signal the boiler, leading to operational issues with the DHW system.

Can I fix it myself? (DIY)

It is not recommended to attempt repairs on the DHW heat exchanger yourself, as this involves gas and electrical components. It is best to call a qualified Gas Safe Engineer to diagnose and resolve the issue safely.

Estimated Repair Cost (2026 UK Prices)

The estimated repair cost for the F48 fault could range from £200 to £400, depending on whether the heat exchanger needs cleaning or replacement. This cost reflects the complexity of the repair and the need for professional expertise.