Emergency
Explosive ignition on Worcester Bosch WR325 RSF

Your boiler is struggling to light smoothly, causing it to build up a small amount of gas before igniting with a loud bang.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Reduced pilot flame or Faulty slow ignition valve

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.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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