High
43 on Alpha E-Tec Plus 10 / 18

Your boiler is struggling to keep its flame lit, which may be caused by strong winds affecting the flue or a technical issue with the burner.

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

Repeated loss of flame signal during operation. This fault can occur if the flue is exposed to high wind conditions (shown as E38 in the fault code history in the INFO menu)

From this model's manual
Verified against the Alpha E Tec Plus 10 18 installation & service manual, page 48.
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

E38View →01View →10View →

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