High
7 50 on Ariston Clas Net One

Your boiler has disabled the central heating system because it can no longer detect or communicate with the equipment that manages how your home is heated.

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

All Heating Zones locked

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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