High
sHr on Grant Vortex Blue

Your boiler has detected an electrical fault with its temperature sensors, which means it cannot accurately measure the water flow and has stopped working for safety.

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

HP flow sensor short / HP return sensor short

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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