High
RED flashing (Reset button) on Grant Vortex Pro 15-26

Your boiler has disabled itself for safety after multiple failed attempts to start the burner, and it now requires a specific cooling period or a professional reset to clear the lock.

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.

What the manual says

Manufacturer manual

Reset push-button locked after being pressed five times in succession without burner restart

From this model's manual
Verified against the Grant Vortexblue Internal Combi Installer Uk Doc 0131 Rev 1 1 October 2020 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 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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