High
10 on Vokera Syntesi 25

Your boiler is attempting to start but is unable to light the burner, meaning it cannot provide you with heating 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

no flame detected

From this model's manual
Verified against the Vokera Linea He installation & service manual, page 33.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's internal control board fails to receive a consistent signal from the sensors that monitor ignition or temperature. The most common reason is a temporary electronic glitch or a sensor starting to fail, which prevents the boiler from confirming it is safe to start the burner.

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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