How much does it cost to fix Grant error code Lockout?

Typical repair cost for the Grant Lockout fault is £120-250 including labour.

Lockout High

Grant Lockout Fault Code

Q: What does the Grant Lockout fault code mean?

Your boiler has stopped because it failed to ignite, so it has safely turned itself off to prevent a build-up of fuel.

Also written as LOCKOUT — same fault.

The Grant Lockout fault code means: your boiler has stopped because it failed to ignite, so it has safely turned itself off to prevent a build-up of fuel.. It appears on 6 Grant models in our database.

Technical description: The 'Lockout' reset button lights if the burner does not light. Wait for about 45 seconds then press the reset button to restart the ignition process.

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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Grant models that show the Lockout fault code

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

Source

Grant Lockout 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