High
105 on Ariston Genus ONE+ WiFi

Your boiler has sensed that water is not moving through the system quickly enough, causing it to overheat and shut down for safety.

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.

What the manual says

Manufacturer manual

Insufficient circulation — flow minus return > 55°C (3 times)

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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

103View →104View →106View →107View →

All 18 fault codes on the Genus ONE+ WiFi

Seeing a different code? Every code this model can display, in one place.

101103104106112114162301302303304313504701702703722

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