What does the Baxi Duo-tec F46 fault code mean?
The F46 fault code on a Baxi Duo-tec boiler indicates a problem with the central heating thermistor, which is responsible for measuring the temperature of the water in the heating system. This fault can lead to inefficient heating or the boiler shutting down to prevent damage.
Common Causes
- Faulty Thermistor: The thermistor may be malfunctioning or damaged, leading to incorrect temperature readings.
- Wiring Issues: There could be a problem with the wiring or connections to the thermistor, causing a loss of signal to the boiler’s 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 gas safety regulations. Attempting to fix it yourself could lead to further complications or safety hazards.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for fixing the F46 fault code is approximately £150 to £200, which includes the replacement of the thermistor and any necessary labour charges. This cost reflects the average price for parts and professional service in the UK.