What does the Ideal Mini F85 fault code mean?
The F85 fault code on the Ideal Mini indicates a problem with the domestic hot water (DHW) system pressure. This typically means that the pressure in the system is either too low or too high, which can affect the boiler’s ability to heat water effectively.
Common Causes
- Low Water Pressure: This can occur due to leaks in the system or insufficient water supply, leading to inadequate pressure for the boiler to operate correctly.
- Faulty Pressure Relief Valve: A malfunctioning pressure relief valve may not maintain the correct pressure, causing the boiler to trigger the F85 fault code.
Can I fix it myself? (DIY)
If you are comfortable with basic plumbing, you can check the pressure gauge on the boiler. If the pressure is below 1 bar, you can safely re-pressurise the system by adding water through the filling loop. However, if you suspect a leak or if the pressure continues to drop, it is essential to call a Gas Safe Engineer.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F85 fault could range from £100 to £250, depending on whether it requires a simple pressure adjustment or the replacement of a faulty pressure relief valve. The cost reflects the need for professional service and potential parts.