How much does it cost to fix Baxi error code Third orange light?

Typical repair cost for the Baxi Third orange light fault is £120-280 including labour.

Third orange light High

Baxi Third orange light Fault Code

Q: What does the Baxi Third orange light fault code mean?

Your boiler is trying to light but the main burner is failing to catch fire, even though the ignition spark is clicking.

Also written as THIRDORANGELIGHT — same fault.

The Baxi Third orange light fault code means: your boiler is trying to light but the main burner is failing to catch fire, even though the ignition spark is clicking.. It appears on 2 Baxi models in our database.

Technical description: Boiler thermostat turned on - spark generator operates

Typical repair cost £120-280 (including labour)

DIY fix possible

Check that your gas supply is turned on at the meterEnsure your thermostat is set higher than the current room temperatureCheck if other gas appliances in your home are working correctly

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Baxi models that show the Third orange light fault code

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

Source

Baxi Third orange light fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.

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