High
AC on Worcester Bosch WR325 RSF

Your boiler has lost communication between its internal computer and a key electrical sensor or motor, meaning it cannot operate safely.

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

No electrical connection between component and PCB

From this model's manual
Verified against the Worcester Bosch Wr325 Rsf 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?

This fault occurs when the boiler's main control board loses its electrical link with a vital internal component, such as a sensor or the fan motor. It is usually caused by a loose connection, a damaged wiring harness, or a failure within the circuit board itself, preventing the boiler from sending or receiving signals. Because the system can no longer monitor safety or performance, it shuts down to prevent damage.

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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Related fault codes

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