Medium
12 on Ariston Euro Combi 30 MFFI

Your boiler is struggling to heat your tap water effectively, meaning it may not reach the desired temperature or the flow is too weak.

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)

DIY fix possible

Check that the cold water mains stopcock is fully openInspect all hot water taps for limescale buildup and clean the aeratorsEnsure the temperature control dial on the front of the boiler is set correctly

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Related fault codes

13View →A03View →

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