High
398 051 on Ideal Mexico Super CF3 40-80

Your boiler has detected a communication failure with the component that controls the gas flow to the burner, meaning the boiler cannot fire up to provide heat.

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

Main burner injector (RS 485)

From this model's manual
Verified against the Ideal Mexico Super Cf3 40 80 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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