High
RED, GREEN blinking inverted on Grant Vortex Eco External Wall Hung

Your boiler has detected an electrical fault in the mechanism that controls the fuel supply, meaning it cannot safely start up to provide heat or hot water.

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

Malfunction in the internal control circuit that drives the oil valve. Faulty oil valve; Internal control circuit that drives the oil valve faulty.

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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