High
ORANGE on Grant Vortex Eco External Floor Standing

Your boiler’s electrical supply is unstable, meaning the electricity coming from your home is not consistent enough for the boiler to operate safely.

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

Frequency supply error

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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