BoilerFaultCodesWhat the manual says
Manufacturer manualFault on Hot Water Sensor
From this model's manual
Verified against the Potterton/Potterton Performa 28i installation & service manual, page 6.
What causes this fault?
This fault occurs when the boiler's internal computer can no longer read a reliable signal from the sensor responsible for monitoring your tap water temperature. The most common reason is that the sensor has either suffered water damage from a small leak or has simply worn out over years of constant heating and cooling.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 21 fault codes on the Performa 28i
Seeing a different code? Every code this model can display, in one place.