High
1 P2 on Ariston Clas One

Your boiler is struggling to move enough water through your heating system, which usually means there is a blockage, air trapped in the pipes, or a pump struggling to work.

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

Insufficient circulation indication

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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Related fault codes

1 P1View →1 P3View →

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