Medium
6-t3 on Worcester Bosch Greenstar 2000

Your boiler is staying on and circulating water continuously because it thinks it is in a permanent cooling-down phase, even when it isn't needed.

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

Permanent pump operation (heating pump): 0...100%.

Engineer required

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

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Related fault codes

6-t1View →6-t2View →

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