High
04 on Saunier Duval Ecosy

Your boiler has lost its electrical power supply, which could be due to a power cut in your home or a tripped fuse.

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

Power supply has been interrupted. This fault code may appear on first commissioning the boiler, or if the power is interrupted while the boiler is in 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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