How much does it cost to fix Ideal error code b 24?

Typical repair cost for the Ideal b 24 fault is £150-300 including labour.

b 24 High

Ideal b 24 Fault Code

Q: What does the Ideal b 24 fault code mean?

Your boiler has detected that water is flowing in the wrong direction or is hotter returning from your radiators than it is leaving the boiler, likely due to a circulation problem.

Also written as B24 — same fault.

The Ideal b 24 fault code means: your boiler has detected that water is flowing in the wrong direction or is hotter returning from your radiators than it is leaving the boiler, likely due to a circulation problem.. It appears on 1 Ideal model in our database.

Technical description: Return temperature > Flow temperature for excessive time

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 24 fault code

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

Imax W Repair: £150-300

Source

Ideal b 24 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