High
Main burner will not light on Worcester Bosch WR325 RSF

Your boiler is failing to ignite the flame needed to heat your water, which could be caused by blocked gas flow or a worn internal component.

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

Gas pressure low, Gas service cock partially closed, Low water rate, Water section diaphragm faulty, or Gas valve faulty

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 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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