High
Neon D on Alpha Cd13r

Your boiler has lost its power connection, meaning it cannot start up or provide any heating and 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

Neon D illuminated continuously - check electrical supply, main terminal fuse, or PCB

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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