High Lockout
E152 on Potterton Gold Combi HE

Your boiler’s internal computer has developed a fault and can no longer communicate with the rest of the system.

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

Internal boiler control board error

What causes this fault?

This fault occurs when the boiler's main electronic brain suffers a critical internal failure or loses its software data. The most common reason is an electrical surge or steady component degradation that prevents the circuit board from processing commands correctly.

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

E133View →E151View →

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