BoilerFaultCodes.com

Keston C40 C55 Combi Fault Codes

Combi Natural Gas 40-55 kW 2013-present
GC Numbers: 47-414-0647-414-07

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Most common fault codes

E00
Your boiler thinks a flame is present even when it should be turned off, which prevents the system from starting up safely.
Gas Safe engineer required · £120-280
E02
Your boiler is failing to light the gas flame despite several attempts, which means your heating and hot water will not work.
May be DIY safe · £120-300
E03
Your boiler has detected a problem with the internal part that controls the gas supply, meaning it cannot ignite to provide heating or hot water.
Gas Safe engineer required · £250-£450

All 15 fault codes

Code Severity Plain English
E00 High Your boiler thinks a flame is present even when it should be turned off, which prevents the system from starting up safely.
E02 High Your boiler is failing to light the gas flame despite several attempts, which means your heating and hot water will not work.
E03 High Your boiler has detected a problem with the internal part that controls the gas supply, meaning it cannot ignite to provide heating or hot water.
E04 High Your boiler has lost power or was turned off while it was already trying to show you a different fault code, masking the original problem.
E11 High Your boiler's computer brain has encountered a serious internal software or hardware glitch and cannot function.
E18 High Your boiler has shut down because the internal water has become too hot, usually because it isn't moving through the pipes properly.
E19 High Your boiler has shut down because the water returning from your radiators is too hot, which usually means the water isn't flowing through your system correctly.
E25 High Your boiler is heating up faster than the water can move away, which usually means something is blocking the flow or the pump isn't circulating water correctly.
E30 High Your boiler has sensed that the water is not moving through the system fast enough, causing it to heat up too quickly and shut down for safety.
E31 High Your boiler has detected a faulty internal temperature sensor, which means it cannot safely measure the heat of the water and has shut down as a precaution.
E32 High Your boiler has detected a fault with the sensor that monitors water temperature returning to the unit, meaning it cannot operate safely or accurately.
E36 High Your boiler has lost its ability to measure the temperature of the water leaving the unit, meaning it cannot operate safely and has shut down.
E37 High Your boiler has detected a communication fault with a internal temperature sensor, preventing the system from monitoring the water returning to the unit safely.
E44 High Your boiler has detected that the water pressure in the system is too low to operate safely, which has caused it to switch itself off.
Enn High Your boiler has encountered a critical system error and has shut itself down as a safety precaution.

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