What does the Baxi Platinum F91 fault code mean?
The F91 fault code on a Baxi Platinum boiler indicates a fault with the central heating (CH) flow rate sensor. This sensor is crucial for monitoring the flow of water through the heating system, and its failure can lead to inefficient heating or system shutdown.
Common Causes
- Blocked or Dirty Sensor: Accumulation of debris or limescale can obstruct the sensor, preventing it from accurately measuring flow rates.
- Electrical Connection Issues: Loose or damaged wiring connections to the sensor can disrupt its function, leading to erroneous readings.
Can I fix it myself? (DIY)
While you can check for visible blockages or clean the sensor, it is strongly advised to call a Gas Safe Engineer for any repairs involving gas or electrical components to ensure safety and compliance with regulations.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for a faulty flow rate sensor on a Baxi Platinum boiler is around £150 to £200. This includes the cost of the replacement part and labour, reflecting the complexity of the repair and the need for a qualified technician.