Low
GREEN ORANGE blinking (0.5s) on Grant Vortex 15-20

Your boiler is currently preparing itself to ignite by clearing out the combustion chamber, which is a normal part of the startup cycle.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Pre-purge

Engineer required

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

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