Main burner will not light High

Worcester Bosch Main burner will not light Fault Code

Q: What does the Worcester Bosch Main burner will not light fault code mean?

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.

Q: How much does it cost to fix Worcester Bosch error code Main burner will not light?

Typical repair cost for the Worcester Bosch Main burner will not light fault is £150-350 including labour.

Also written as MAINBURNERWILLNOTLIGHT — same fault.

The Worcester Bosch Main burner will not light fault code means: 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.. It appears on 1 Worcester Bosch model in our database.

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

Typical repair cost £150-350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Worcester Bosch models that show the Main burner will not light fault code

Click a model for the full fault code list and model-specific repair notes.

WR325 RSF Repair: £150-350

Source

Worcester Bosch Main burner will not light fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026