High
AC on Worcester Bosch Highflow 250

Your boiler has lost communication with one of its internal control units, meaning it cannot properly manage your heating or hot water functions.

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

Module not detected (either heat or water)

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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