High
E04 on Potterton Promax 15/2 HE Plus

Your boiler has stopped because it can no longer detect the flame needed to heat your 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.

Technical description

Flame failure (loss of flame during operation)

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

E03View →E05View →E11View →

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