High Lockout
A62 on Ferroli BlueHelix Pro 25C

Your boiler has switched itself off because the main control board is unable to talk to the gas valve that fuels the flames.

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 communication between PCB and gas valve

What causes this fault?

This fault occurs when the boiler's internal computer tries to send a signal to the gas valve to release fuel but receives no response. The most common cause is an electronic failure within the gas valve itself or a broken connection in the wiring that links these two critical parts.

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

A01View →

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