How much does it cost to fix Ideal error code b 65?

Typical repair cost for the Ideal b 65 fault is £150-300 including labour.

b 65 High

Ideal b 65 Fault Code

Q: What does the Ideal b 65 fault code mean?

Your boiler is struggling to confirm that the internal air fan is spinning correctly to clear waste gases, so it has paused start-up as a safety precaution.

Also written as B65 — same fault.

The Ideal b 65 fault code means: your boiler is struggling to confirm that the internal air fan is spinning correctly to clear waste gases, so it has paused start-up as a safety precaution.. It appears on 1 Ideal model in our database.

Technical description: Waiting for fan tacho signal at start up

Typical repair cost £150-300 (including labour)

Engineer required

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

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Ideal models that show the b 65 fault code

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

Imax W Repair: £150-300

Source

Ideal b 65 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.

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