High Lockout
E5 on Remeha Quinta Ace 25

Your boiler has stopped working because the fan system that safely clears away waste gases is not operating correctly.

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

Fan error or differential air pressure switch failure

What causes this fault?

This fault occurs when the boiler's internal computer detects that the fan is not spinning fast enough to safely vent exhaust fumes outside. The most common reason is a mechanical failure within the fan motor itself or a blockage in the small air tubes that monitor pressure. Without a signal confirming that the air is moving safely, the boiler will shut down as a safety precaution.

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

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