High
APS Stuck Fault on Potterton Suprima HE

Your boiler has detected that a safety sensor is stuck in the 'on' position before the fan has even started, so it has stopped working as a precaution.

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

Automatic reset. Air Proving Switch stuck in the closed position.

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

E110View →E119View →

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