Medium
Short Cycling on Worcester Bosch Greenstar 27CDi

Your boiler is rapidly turning itself on and off because it cannot efficiently heat the water circulating through your radiators.

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

Burner rating incorrect; Boiler thermostat differential incorrect; External controls not operating correctly

Engineer required

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

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