How much does it cost to fix Baxi error code Air pressure switch not proved?

Typical repair cost for the Baxi Air pressure switch not proved fault is £120-250 including labour.

Air pressure switch not proved High

Baxi Air pressure switch not proved Fault Code

Q: What does the Baxi Air pressure switch not proved fault code mean?

Your boiler is failing to detect that the fan is pushing burnt gases safely out of the flue, so it has shut down to prevent unsafe operation.

Also written as AIRPRESSURESWITCHNOTPROVED — same fault.

The Baxi Air pressure switch not proved fault code means: your boiler is failing to detect that the fan is pushing burnt gases safely out of the flue, so it has shut down to prevent unsafe operation.. It appears on 1 Baxi model in our database.

Technical description: Go to section 'E' - Check electrical and pressure tube connections, blockage of tubes, restriction in flue, or venturi.

Typical repair cost £120-250 (including labour)

Engineer required

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

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Baxi models that show the Air pressure switch not proved fault code

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

Combi 80e Repair: £120-250

Source

Baxi Air pressure switch not proved 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