BoilerFaultCodes.com

Ideal Logic Combi C24 C30 C35 Fault Codes

Combi Natural Gas 24-35 kW 2013-present
GC Numbers: 47-348-5647-348-5747-348-58

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Most common fault codes

F
Your boiler has identified an internal problem and is displaying a specific code number to help pinpoint the exact technical issue.
Gas Safe engineer required · £100-450
F1
Your boiler has detected that the water pressure inside the system is too low to run safely and has stopped working as a result.
May be DIY safe · £0-120
F2
Your boiler is failing to stay lit or cannot detect its own flame, meaning it has shut down for safety and will not provide heating or hot water.
May be DIY safe · £100-280

All 35 fault codes

Code Severity Plain English
dU Low Your boiler is not broken; it is simply in a special service mode used by engineers when they are preparing to replace internal parts.
F High Your boiler has identified an internal problem and is displaying a specific code number to help pinpoint the exact technical issue.
F1 High Your boiler has detected that the water pressure inside the system is too low to run safely and has stopped working as a result.
F2 High Your boiler is failing to stay lit or cannot detect its own flame, meaning it has shut down for safety and will not provide heating or hot water.
F2 or Fn or Ln High Your boiler has started an ignition process but the flame has gone out, meaning the system has shut down for safety.
F3 High Your boiler has detected an issue with the internal fan, which is preventing the system from safely clearing exhaust gases and starting the ignition process.
F4 High Your boiler has detected an issue with the sensor that monitors the temperature of the water leaving the unit, meaning it cannot safely regulate heat.
F5 High Your boiler has detected an issue with the sensor that monitors the temperature of the water returning to the unit, causing it to stop working for safety.
F6 Low Your boiler has lost connection with the sensor that monitors the outdoor temperature, making it difficult for the system to adjust its heat settings efficiently.
F7 High Your boiler has detected that the electricity supply coming into your home is at a lower voltage than it needs to operate safely.
F8 High Your boiler's computer brain has lost its settings or is experiencing an electrical fault, preventing the system from starting up.
F9 High Your boiler's computer memory is blank or incorrect, meaning it doesn't currently know how to operate itself.
FA High Your boiler has detected that the water temperature sensors are giving conflicting readings, often caused by the flow and return pipes being switched or a sensor failing.
FL Medium Your boiler is displaying an error code for a feature that isn't actually used on this model, which usually indicates a simple electronic glitch or a programming error.
Fn High Your boiler has lit correctly but the flame has gone out unexpectedly, often due to a temporary interruption in the gas supply or a blocked condensate pipe.
FU High Your boiler has detected that the water is heating up too quickly or isn't moving through the system properly, causing it to overheat and shut down for safety.
L High Your boiler has stopped working and locked itself to prevent damage, requiring you to identify the specific number following the L code to find the exact fault.
L1 High Your boiler has shut down because the water inside it has become too hot, usually due to a lack of circulation or a blockage in the system.
L2 High Your boiler has stopped working because it cannot light a flame, which is often caused by a lack of gas supply or a blocked pipe.
L4 High Your boiler has detected a problem with the internal temperature sensor that monitors the water leaving the unit, causing it to shut down as a safety precaution.
L5 High Your boiler has detected a problem with the sensor that monitors the temperature of the water coming back into the unit, causing it to shut down for safety.
L6 High Your boiler thinks a flame is present even though it hasn't been safely ignited, causing the system to shut down for safety.
L8 High Your boiler's computer brain has lost its settings or is experiencing an electrical fault, preventing the system from starting up.
L9 High Your boiler's computer brain has lost its settings or is experiencing an electrical fault, preventing the system from starting up.
LC High Your boiler has tried and failed to start up five times in a short window and has now locked itself out for safety.
Ln High Your boiler is struggling to keep its flame lit, which means it cannot heat your water or radiators reliably.
oF High Your boiler is in a standby or programming mode and thinks it has been told to stay switched off.
P1 Low Your boiler is displaying a service setting notification rather than a breakdown, indicating the internal pump is being told to run at its maximum speed.
P7 Low Your boiler is displaying a configuration setting rather than a breakdown, indicating the internal pump is set to its standard minimum operating speed.
SE Low Your boiler is simply reminding you that its annual service is due soon; it is a notification rather than a breakdown.
SH Low Your boiler is not in a fault state; it is simply running in a manual test mode designed for service engineers to check its performance.
SL Low Your boiler is currently running a service test at its lowest power setting and this is a status indicator rather than a functional error.
UF Low Your boiler is currently set to a professional test mode for servicing and is not in its normal operating state.
uP High Your boiler is currently stuck in its startup or programming sequence and is not yet ready to provide heat or hot water.
VF Low Your boiler is performing a routine self-cleaning process to remove air bubbles from the system and is not actually reporting a hardware fault.

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