High
RED LED on continuously on Potterton Prima 30B

Your boiler has detected a failure and stopped working as a safety precaution, likely because it has overheated or is receiving an incorrect signal from your thermostat.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Indicates a fault condition, possibly related to overheat or external controls

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

Flashing Red LEDView →

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