High
A8 362 on Worcester Bosch 24 RSF

Your boiler is struggling to operate because it is receiving an unsteady or insufficient supply of electricity.

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

Low mains voltage – the voltage may be interrupted, inconsistent or heat control module (HCM) invalid

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

A8View →

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