Emergency
143 on Grant Vortex 15-20

Your boiler is struggling to get the right amount of air, which usually means the permanent ventilation opening in the room is obstructed or insufficient for the appliance to run safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Vent A (cm²)

From this model's manual
Verified against the Grant Vortex Eco installation & service manual, page 30.
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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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