High
Mains LED off on Baxi 800 Heat (range)

Your boiler has lost all power and is completely shut down, meaning it cannot provide any 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.

Technical description

Mains supply failure, fuse failure, or control PCB/transformer fault.

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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