High
235 on Worcester Bosch Hideaway

Your boiler's internal computer parts are talking to each other using different languages and need a software update or a compatible replacement part to work together properly.

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

Incompatible heat control module (HCM) software versions – control box needs latest software

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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