High
E127 on Navien LCB700

Your boiler is struggling to detect the necessary airflow required to operate safely, which has caused it to shut down to prevent any risk.

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

Abnormal operation: APS

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

E003View →E110View →

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