High
FAIL POINT J on Worcester Bosch 28 RSF

Your boiler is having trouble breathing, likely because air isn't moving through the flue correctly or a sensor is misreading the airflow.

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

Air Pressure Fault: Fan failure, air pressure switch shorting, pressure switch not closing (venturi/tube blockage), or flue restriction.

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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