BoilerFaultCodes.com

Ideal Logic Max System / Logic Plus System Fault Codes

System Natural GasLPG 15-30 kW 2018-present
GC Numbers: 41-750-8441-750-8541-750-8641-750-8741-750-88

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Most common fault codes

F1
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
May be DIY safe · £0-120
F2, FN or LN
Your boiler has failed to light or maintain a flame, meaning your heating and hot water have stopped working.
May be DIY safe · £100-£350
F3
Your boiler has stopped working because the internal fan, which safely removes waste gases from your home, is not spinning correctly.
Gas Safe engineer required · £280-450

All 18 fault codes

Code Severity Plain English
F1 High Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
F2, FN or LN High Your boiler has failed to light or maintain a flame, meaning your heating and hot water have stopped working.
F3 High Your boiler has stopped working because the internal fan, which safely removes waste gases from your home, is not spinning correctly.
F4 High Your boiler has stopped working because it cannot correctly detect how much water is flowing through the system or what the temperature is.
F5 High Your boiler has stopped working because it cannot properly measure the temperature of the water returning from your radiators.
F6 Low Your boiler has lost connection with the sensor that measures the temperature outside, which helps it run more efficiently.
F7 High Your boiler has stopped working because the electricity supply coming into your home is currently too weak to power the internal electronics safely.
F8 High Your boiler's internal computer has forgotten its settings or has developed a technical communication error, meaning it cannot safely control the heating process.
F9 High Your boiler's internal computer has forgotten its settings or has developed a technical communication error, meaning it cannot safely control the heating process.
FU High Your boiler has detected that heat is not moving away from the unit quickly enough, often because water flow is being blocked or restricted.
L1 High Your boiler has shut down because it has detected it is getting too hot or there isn't enough water moving through the system to keep it cool.
L2 High Your boiler has tried to light several times but cannot establish a flame, meaning your heating and hot water will not work until it is reset or repaired.
L4 High Your boiler has stopped working because it cannot correctly detect how much water is flowing through the system or what the temperature is.
L5 High Your boiler has stopped working because it cannot properly measure the temperature of the water returning from your radiators.
L6 High Your boiler thinks it sees a flame even though it isn't currently firing, causing it to shut down as a safety precaution.
L8 High Your boiler's internal computer has forgotten its settings or has developed a technical communication error, meaning it cannot safely control the heating process.
L9 High Your boiler's internal computer has forgotten its settings or has developed a technical communication error, meaning it cannot safely control the heating process.
LC Low Your boiler is undergoing a restart process, usually following a fault or power interruption, and is attempting to fire up correctly.

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