How much does it cost to fix Grant error code GREEN blinking (0.5s)?

Typical repair cost for the Grant GREEN blinking (0.5s) fault is £120-250 including labour.

GREEN blinking (0.5s) Medium

Grant GREEN blinking (0.5s) Fault Code

Q: What does the Grant GREEN blinking (0.5s) fault code mean?

Your boiler is currently undergoing a safety timing delay, which typically occurs after it has failed to ignite successfully on the first attempt.

Also written as GREENBLINKING05S — same fault.

The Grant GREEN blinking (0.5s) fault code means: your boiler is currently undergoing a safety timing delay, which typically occurs after it has failed to ignite successfully on the first attempt.. It appears on 5 Grant models in our database.

Technical description: Safety time

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 GREEN blinking (0.5s) fault code

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

Source

Grant GREEN blinking (0.5s) 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