High
750 on Ariston Alteas One

Your boiler has disabled all heating areas, meaning your radiators will not warm up until the control system is reset or communicating correctly.

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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Related fault codes

701View →702View →703View →

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