BoilerFaultCodesKeston E02 Fault Code
The Keston E02 fault code means: your boiler thinks a flame has started when it shouldn't have, usually caused by an electrical glitch or a faulty sensor signal.. It appears on 9 Keston models in our database.
Technical description: False flame - There is possibly a problem with the power supply.
What causes the Keston E02 fault?
This fault occurs when the boiler's control system detects a flame signal at a time when there shouldn't be a fire, such as during the startup checks. The most common reason is a sensor that has become damp or damaged and is sending a 'ghost' signal, or a fault within the main circuit board that is misreading electrical noise as a flame.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Keston models that show the E02 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Keston E02 fault code information on this page is sourced and cross-checked against the official Keston service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026