Medium
Blinking RED on Grant Vortex Eco

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.

What the manual says

Manufacturer manual

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.

From this model's manual
Verified against the Grant Vortex Eco installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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