Medium
9 on Ariston Genus 30 Plus

Your boiler has noticed that the water circulating through your radiators is not getting as warm as it should.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Insufficient radiator temperature - check C.H. temperature probe, check by-pass, check gas pressures

From this model's manual
Verified against the Ariston/Ariston Genus 30 Plus 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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All 10 fault codes on the Genus 30 Plus

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

1234567830 40 50 60 70 80

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