High
E73 on Biasi Rinnova Adaptive Combi

Your boiler has stopped working because one of its internal sensors is sending incorrect information while the system tries to perform an automatic self-check.

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

C.H. heating delivery probe NTC or return probe NTC or Flue gas NTC or D.H.W. NTC fault during calibration

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

E74View →E75View →

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