High
Water pressure on Saunier Duval Thema F 30 E Plus

Your boiler has detected that the amount of water circulating through your heating system is too low, so it has safely stopped working to prevent any damage.

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 pressure warning; check water pressure.

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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