High
Lockout on Saunier Duval SD 30e

Your boiler has stopped working because it cannot successfully start or maintain a flame, so it has safely shut itself down to prevent gas from building up.

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

Appliance goes to lockout - check if burner is cross lighting, check sensing lead and electrode continuity, or replace P.C.B.

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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