Emergency
01 on Vokera Syntesi 25E / 29E

Your boiler has failed to ignite because it is not receiving gas or has detected an issue with the internal airflow, meaning you currently have no heating or hot water.

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

Gas supply problem, Gas line requires purging, Reversed polarity, Broken, internal flue joint

From this model's manual
Verified against the Vokera Syntesi 25e 29e 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.

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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