High
7 50 on Ariston E-Combi One 24

Your boiler has disabled your heating system across all zones because it cannot detect a valid control signal or has experienced a communication failure between the thermostats and the main unit.

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

7 01View →7 02View →

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