Medium
286 D1 on Worcester Bosch Greenstar 12i System

Your boiler has detected that the water returning to it is too hot, causing it to pause heating to prevent damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

Return temperature too high

Engineer required

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

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