Medium Warning
27 on Potterton Performa 24

Your boiler is struggling to correctly measure the temperature of your hot water, which usually means your taps will only provide lukewarm or cold water.

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

Fault on Hot Water Sensor

What causes this fault?

This fault occurs when the boiler's internal computer stops receiving a reliable signal from the sensor that monitors your tap water temperature. The most common reason is that the sensor has physically degraded or developed an electrical short, preventing it from telling the boiler to turn the burner on for hot water.

Engineer required

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

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