High
E74 on Biasi Rinnova Adaptive Combi

Your boiler is struggling to detect a rise in temperature while trying to set itself up, which usually means the water isn't moving through the system properly.

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

No temperature increase during calibration (Delivery = Return)

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

E75View →

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