High
Mains light off on Ideal Concord Super Series 4

Your boiler has lost all electrical power, meaning it cannot provide any heating or hot water until the power supply is restored.

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

Check external fuses, module on/off switches, electrical connections, or Board No. 30.

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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