Medium
5-A3 on Worcester Bosch Greenstar 2000

Your boiler is struggling to run at its lowest power setting, which can cause it to shut down for safety while heating your home or water.

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

Minimum boiler output (heating and DHW).

Engineer required

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

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Related fault codes

5-A1View →5-A2View →

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