High
Flashes red on Grant Vortex 15-20

Your boiler has stopped heating because the internal water pump, which moves hot water around your house, has seized up or failed and cannot restart itself.

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 not operating. Pump stopped (blocked). Pump does not restart itself due to a permanent failure.

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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