High
Flashes red/green on Grant Vortex Eco

Your boiler is struggling because the internal water pump is stuck or not receiving power, which prevents heat from circulating through your home.

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

Pump stopped (blocked): Water flowing thorugh pump but no mains voltage to motor

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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