Low
1-d4 on Worcester Bosch Greenstar 8000 Style

Your boiler is having trouble communicating with your solar water heating system, which may prevent the solar panels from boosting your hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Solar unit fault

Engineer required

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

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