High
Low water pressure LED on Saunier Duval SD 30e

Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.

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

Flashing - check system pressure, re-pressurise if necessary, or check/replace low water pressure switch

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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