29 High

Grant 29 Fault Code

The Grant 29 fault code means: your boiler is struggling to clear exhaust gases effectively because the internal fan or air sensors are not working as they should, causing the system to stop for safety reasons.. It appears on 1 Grant model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Air Pressure Error
Typical repair cost £180-350 (including labour)

Engineer required

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

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Grant models that show the 29 fault code

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

Source

Grant 29 fault code information on this page is sourced and cross-checked against the official Grant service / installation manuals for each affected model.

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