Medium
A8 on Worcester Bosch Greenstar 30si

Your boiler has lost its connection to the remote programmer or thermostat on your wall, preventing it from receiving instructions on when to turn the heating on.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Break in communication to the DT10/DT20 or FR10/FR110

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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