Medium Warning
28 on Potterton Performa 30 HE

Your boiler's hot water sensor has stopped working correctly, which means you may have inconsistent or no hot water.

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.

Technical description

Fault on Hot Water Sensor

What causes this fault?

This fault occurs when the domestic hot water sensor, which monitors the temperature of the water going to your taps, provides an incorrect or missing electrical signal to the main control board. The most common reason is that the internal sensor has degraded over time or developed a short circuit, preventing the boiler from knowing how hot the water actually is. In some cases, it can also be caused by loose or corroded wiring connections between the sensor and the boiler’s brain.

Engineer required

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

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