High Lockout
E151 on Potterton Gold Combi HE

Your boiler's computer brain has encountered an internal software or electronic 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 control board suffers an internal electronic failure, similar to a computer crashing or a circuit shorting out. It is often caused by aged components on the circuit board losing their ability to process signals, or occasionally by a sudden power surge that damages the sensitive microprocessors.

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

E152View →E153View →

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