How much does it cost to fix Baxi error code H.03 – .02?

Typical repair cost for the Baxi H.03 – .02 fault is £120-350 including labour.

H.03 – .02 High

Baxi H.03 – .02 Fault Code

Q: What does the Baxi H.03 – .02 fault code mean?

Your boiler has lost its flame while it was running, which means it has stopped providing heating and hot water for safety reasons.

Also written as H0302 — same fault.

The Baxi H.03 – .02 fault code means: your boiler has lost its flame while it was running, which means it has stopped providing heating and hot water for safety reasons.. It appears on 24 Baxi models in our database.

Technical description: Flame error – no flame during operation.

What causes the Baxi H.03 – .02 fault?

This fault occurs when the boiler successfully lights but the internal sensors lose track of the flame while it is firing. It is often caused by a dirty or worn-out sensing probe that can no longer 'see' the fire, or a faulty gas valve that isn't providing a steady enough flow of fuel to maintain the combustion. Without a stable signal that the flame is safely lit, the boiler shuts down as a protective measure.

Typical repair cost £120-350 (including labour)

DIY fix possible

Check if other gas appliances in your home, like a hob, are working to confirm gas supply.Ensure your gas meter has credit if you use a prepay meter.Press and hold the Reset button for five seconds to see if the boiler restarts.

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Baxi models that show the H.03 – .02 fault code

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

Source

Baxi H.03 – .02 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