High
F03 on Heatline Sargon 30

Your boiler is struggling to detect if the internal fan is spinning correctly, which causes it to shut down for your safety to prevent the build-up of harmful exhaust gases.

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

Fan tachometer

From this model's manual
Verified against the Heatline/Heatline Sargon 24 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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Related fault codes

F02View →F05View →

All 18 fault codes on the Sargon 30

Seeing a different code? Every code this model can display, in one place.

CCF0F1F01F2F02F3F4F04F5F05F6F06F07F8F9OC

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