BoilerFaultCodesGrant 61 Fault Code
The Grant 61 fault code means: your boiler is struggling to breathe because the permanent air vent in the room is either blocked, undersized, or has been covered, preventing the unit from getting enough oxygen to run safely.. It appears on 6 Grant models in our database.
Technical description: Vent B (in²)
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 61 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Grant 61 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 7 July 2026