Medium
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.

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.

What the manual says

Manufacturer manual

Fault on Hot Water Sensor

From this model's manual
Verified against the Potterton Performa 24 installation & service manual, page 6.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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