What does the Ideal Logic Max F42 fault code mean?
The F42 fault code on the Ideal Logic Max indicates a system pressure fault, which typically means that the pressure in the heating system is either too low or too high. This can lead to inadequate heating performance and may require immediate attention to prevent further issues.
Common Causes
- Low System Pressure: This can occur due to leaks in the system, air trapped in the radiators, or insufficient water in the system.
- High System Pressure: This may be caused by a faulty pressure relief valve or an issue with the expansion vessel, leading to excessive pressure buildup.
Can I fix it myself? (DIY)
If the system pressure is low, you can attempt to repressurise the system using the filling loop. Ensure the boiler is off, locate the filling loop, and open the valves to add water until the pressure gauge reads between 1-1.5 bar. If the pressure is high or if you are unsure, it is strongly advised to call a Gas Safe Engineer.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing a pressure fault on an Ideal Logic Max could range from £100 to £300, depending on whether it involves simply repressurising the system or replacing components like the pressure relief valve or expansion vessel.