High
59 on Alpha Intec2 25 28XE

Your boiler is struggling because it is sensing an unstable or incorrect electrical power supply from your home's mains.

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

Mains supply voltage frequency block. The PCB detects an incorrect mains supply voltage frequency

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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