Medium
265 on Worcester Bosch Greenstar 30i

Your boiler is temporarily limiting its power output to prevent overheating because it is struggling to move heat away from the unit quickly enough.

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

The boiler is waiting in response to a heat demand – the boiler regularly switches to partial load

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that all radiator valves are fully openEnsure the system pressure is between 1 and 1.5 bar on the gaugeBleed all radiators to remove trapped airPress the reset button to see if the fault clears

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