High
Insufficient System Pressure on Ariston Excalibur

Your boiler has stopped working because the water pressure inside the 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

Shutdown occurs in the event of insufficient water pressure in the heating system (less than 0.4 bar). Resets automatically once pressure reaches 1.5 bar.

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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