What does the Ideal Mini F90 fault code mean?
The F90 fault code on the Ideal Mini boiler indicates a problem with the return temperature sensor in the central heating system. This fault typically suggests that the return temperature is outside the expected range, which can affect the boiler’s efficiency and operation.
Common Causes
- Blocked Return Pipe: A blockage in the return pipe can prevent proper flow, leading to incorrect temperature readings.
- Faulty Temperature Sensor: A malfunctioning temperature sensor may provide inaccurate readings, triggering the F90 fault code.
Can I fix it myself? (DIY)
If you are comfortable with basic plumbing, you can check for blockages in the return pipe and clear them if necessary. However, for issues related to the temperature sensor or any gas/electrical components, it is strongly advised to call a Gas Safe Engineer.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving an F90 fault code is around £150 to £250, primarily depending on whether the temperature sensor needs replacing or if there are blockages that require professional clearing.