Medium
12 on Ariston Euro Prisma 24

Your boiler is struggling to reach the correct temperature for your hot water, likely due to a build-up of limescale or a faulty internal sensor.

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

Check of domestic hot water production efficiency (delivery rate and temperature)

Engineer required

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

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