High
APS Cycling LOCKOUT on Potterton Suprima HE

Your boiler has detected an issue with its internal ventilation system four times in a row, causing it to shut down for safety reasons.

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

The Air Pressure Switch is not maintaining its signal. This has occurred 4 times.

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

E119View →E133View →

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