High Lockout
E0 on Remeha Quinta Ace 25

Your boiler's main internal computer has developed a fault and cannot process commands properly.

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 critical communication failure or hardware malfunction. It is usually caused by electrical components wearing out over time or damage from a sudden power surge that disrupts the brain of the appliance. Because the control board can no longer safely manage the heating process, the system shut downs entirely to prevent any unsafe operation.

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

E1View →E2View →E4View →

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