Medium
265 on Worcester Bosch Greenstar 1000

Your boiler is temporarily turning itself off because your radiators or taps aren't taking away the heat as fast as the boiler is producing it, often due to poor water flow.

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

Heat demand lower than energy supplied

From this model's manual
Verified against the Worcester Bosch Worcester Bosch Greenstar 1000 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.

What causes this fault?

Energy imbalance

Engineer required

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

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