High
01 on Vokera Synergy 25 E

Your boiler is failing to light because it cannot detect a flame, meaning you currently have no 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

Gas supply problem, Gas line requires purging, Reversed polarity, Broken, internal flue joint, or the burner has failed to ignite, or the flame supervision system has failed to detect a flame.

From this model's manual
Verified against the Vokera/Vokera Synergy 25 E installation & service manual, page 29.
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

02View →03View →

All 11 fault codes on the Synergy 25 E

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

0203040506070809d1d2

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