High
FAIL POINT D on Worcester Bosch 28 RSF

Your boiler's electronic control system is experiencing a fault, which is preventing it from starting up or 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

Electronic programmer fault at position ST5.

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

FAIL POINT CView →FAIL POINT EView →

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