Medium
Blinking RED on Grant Vortex 15-20

Your boiler has detected that it is running too hot and has automatically slowed itself down to prevent any damage to its internal components.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Thermal self-protection mode. The fluid temperature exceeds the maximum value at a specific ambient temperature. The pump will automatically reduce power consumption, speed, and performance.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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