Low
265 on Worcester Bosch Greenstar 4000

Your boiler is struggling because it is producing more heat than your home or radiators are currently asking for, causing the system to stop temporarily.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Heat demand lower than energy supplied

From this model's manual
Verified against the Worcester Bosch Greenstar 4000 installation & service manual, page 73.
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 at least two or three radiator valves (TRVs) are fully openEnsure the central heating system is not restricted by closed bypass valvesWait for the boiler to automatically restart once the temperature dropsPerform a simple reset if the code persists

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