Emergency
F1 on Ravenheat CSI 120

Your boiler is struggling to detect the correct airflow required to burn gas safely, which has caused it to shut down to prevent potential hazards.

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

orifice plate

From this model's manual
Verified against the Ravenheat He 80 90 25 30s Combi installation & service manual, page 46.
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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Related fault codes

F2View →F3View →

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