High
2 flashes on Worcester Bosch Greenstar 35 CDi

Your boiler is struggling to circulate water because there isn't enough pressure or there is air trapped in the system.

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

Pump has run dry.

From this model's manual
This code was read directly from the manufacturer service manual for this model.
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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Avoid the next call-out bill

A cover plan would handle faults like 2 flashes: no call-out fees, no surprise bills.

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