BURNER LIGHT ONLY Low

Worcester Bosch BURNER LIGHT ONLY Fault Code

Also written as BURNERLIGHTONLY — same fault.

The Worcester Bosch BURNER LIGHT ONLY fault code means: your boiler is currently protecting itself from freezing by running in a special cold-weather mode, or the status light on your display has broken.. It appears on 2 Worcester Bosch models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: If boiler is in a very cold environment (below 5°C), boiler is running in 'Autofroststat' mode. Otherwise, demand light has failed.
Typical repair cost £100-180 (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 BURNER LIGHT ONLY fault code

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

Source

Worcester Bosch BURNER LIGHT ONLY 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