Medium
Limescale Build-up on Ariston Euro Prisma 24

Your boiler has detected mineral deposits inside its heating components and is automatically lowering the water temperature to prevent further damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Technical description

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.

Engineer required

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

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