High
L.E.D. D on Ariston Genus Premium

Your boiler has detected that there is not enough water pressure flowing through the system to heat your home safely.

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

Circulation Failure: This control signals that the safety pressure switch on the primary circuit has not sensed a pressure of at least 1.5 bar within 40 seconds of the activation of the circulation pump.

From this model's manual
Verified against the Ariston Genus 27 Rffi System installation & service 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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