High Lockout
E05 on Remeha Quinta 115

Your boiler’s internal computer has encountered a critical error and cannot communicate properly to manage the heating process 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 box error

What causes this fault?

This fault occurs when the boiler's internal computer experiences a hardware failure or a memory corruption loop. The most common reason is that the printed circuit board has worn out over time or has been damaged by a sudden electrical surge, preventing it from processing safety information.

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 →E07View →

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