What does the Baxi 433 fault code mean?

Your boiler has shut down because the water inside it has become dangerously hot, likely because it isn't circulating through your radiators properly.

How much does it cost to fix Baxi error code 433?

Typical repair cost for the Baxi 433 fault is £120-£350 including labour.

Can I fix Baxi fault code 433 myself?

Ensure all radiator valves (TRVs) are turned to the highest setting

Baxi 433 Fault Code: What It Means & How to Fix It

Technical description

Heat exchanger temperature exceeded (greater than 95 degrees)

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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Related fault codes

432View →

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Your boiler has shut down because the water inside it has become dangerously hot, likely because it isn't circulating through your radiators properly.

Technical description

Engineer required

Related fault codes

Related guides you might find useful

Banging / kettling / whistling noise

Boiler won't turn on — 9-step checklist

Boiler keeps cutting out

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