What does the Baxi Duo-tec F87 fault code mean?
The F87 fault code on a Baxi Duo-tec boiler indicates a domestic hot water (DHW) maintenance fault. This typically suggests an issue with the boiler’s ability to heat water for taps and showers, which may require attention to restore proper function.
Common Causes
- Blocked Heat Exchanger: A buildup of limescale or debris can obstruct the heat exchanger, preventing efficient water heating.
- Faulty DHW Sensor: If the sensor that monitors the temperature of the hot water is malfunctioning, it may incorrectly signal a fault.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it may involve gas or electrical components that require professional handling. Attempting to fix these without proper qualifications can be dangerous.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving an F87 fault could be around £150 to £250, depending on whether the heat exchanger needs cleaning or the DHW sensor needs replacement. This cost reflects the complexity of the repairs and the need for professional expertise.