High Lockout
E29 on Intergas Combi Compact HRE SB

Your boiler's electronic brains have encountered an internal software or communication error and can no longer control the heating safely.

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 control error

What causes this fault?

This fault occurs when the boiler's internal computer chips fail to talk to each other correctly or lose programmed data. It is usually caused by a physical hardware failure within the main control board or a sudden electrical surge that has corrupted the system's memory.

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

E01View →E31View →

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