What does the Glow-worm Betacom F86 fault code mean?
The F86 fault code on the Glow-worm Betacom indicates a problem with the central heating return temperature sensor. This sensor is crucial for monitoring the temperature of the water returning to the boiler, and a fault can disrupt the heating system’s operation.
Common Causes
- Faulty Temperature Sensor: The sensor may be damaged or malfunctioning, 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 to diagnose and repair this issue, as it involves electrical components and safety risks associated with gas appliances.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing the central heating return temperature sensor is around £120-£150. This includes the cost of the part and labour, as sensor replacement typically requires professional expertise.