What does the Glow-worm Betacom F85 fault code mean?
The F85 fault code indicates a problem with the domestic hot water (DHW) return temperature sensor in the Glow-worm Betacom boiler. This sensor is crucial for monitoring the temperature of the water returning from the heating system, and a fault can disrupt the boiler’s operation.
Common Causes
- Faulty Temperature Sensor: The sensor may be malfunctioning or damaged, leading to incorrect temperature readings.
- Wiring Issues: Damaged or loose wiring connections to the sensor can cause communication failures between the sensor and the boiler control board.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it involves electrical components and safety risks. Attempting to fix it yourself could lead to further damage or safety hazards.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing the DHW return temperature sensor is around £150. This includes the cost of the part and labour, as sensor replacements typically require professional installation to ensure proper functioning.