High
C 78 on Atag A200

Your boiler is struggling to circulate water, either because there isn't enough water inside the system or because the internal pump has stopped working.

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

Water pressure outside of range or not connected or if water pressure is OK: Pump failure

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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