High
OFF on Grant Vortex 15-20

Your boiler has lost all power and is completely shut down, meaning it cannot provide any heating or hot water until the electrical supply is restored.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Lack of electrical supply. Check presence of voltage in the L - N of the four pin plug. Check the conditions of the fuses. Check that safety thermostat is not in lockout.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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