BoilerFaultCodesPotterton 30° neon flashing Fault Code
Also written as 30NEONFLASHING — same fault.
The Potterton 30° neon flashing fault code means: your boiler has detected an issue with the sensor that monitors the water temperature, causing the system to shut down as a safety precaution.. It appears on 3 Potterton models in our database.
Technical description: Primary temperature sensor (NTC) fault
What causes the Potterton 30° neon flashing fault?
This fault occurs when the sensor responsible for monitoring the heat of the water inside the boiler fails or sends an incorrect signal. The most common reason is that the sensor has physically degraded over time or developed an electrical short, meaning the boiler can no longer safely track temperature. Because the system doesn't know how hot the water is, it shuts down to prevent the unit from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Potterton models that show the 30° neon flashing fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Potterton 30° neon flashing fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026