High
Blue indicator light off on Worcester Bosch 28i RSF

Your boiler has no power and is completely switched off, meaning you have no heating or hot water until the electrical supply is restored.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

The appliance is switched off via the master switch or there is no power supply to the appliance.

From this model's manual
Verified against the Worcester Boiler 24i Junior 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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