Medium
Limescale Build-up on Ariston Eurocombi 20 1mfs

Your boiler has detected that built-up mineral deposits are preventing your water from heating efficiently, so it has capped the temperature to protect the system from further damage.

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

Indirect control (actuated through the regulation of the temperature in the primary heat exchanger) on the formation of limescale in the secondary heat exchanger; temperature is limited to 62°C.

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

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All 8 fault codes on the Eurocombi 20 1mfs

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

BOILER SHUTDOWNFlame failureIgnition LockoutINSUFFICIENT WATERL.E.D. DL.E.D. GSafety Shut-off

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