Low
7 04 on Ariston E-Combi One

Your boiler is having trouble reading the temperature in one of your heating zones, which may cause that specific part of your system to stop heating correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Zone 3 return sensor defective

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

7 02View →7 03View →

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