Medium
Short Cycling on Worcester Bosch Greenstar Utility

Your boiler is rapidly turning itself on and off because it is struggling to regulate its temperature or is getting conflicting signals from your wall thermostat.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Worcester Bosch Greenstar Camray Utility installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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