BoilerFaultCodesWhat the manual says
Manufacturer manualFault with the temperature sensor
From this model's manual
Verified against the Worcester Bosch Wr325 Rsf installation & service manual.
What causes this fault?
This fault occurs when the boiler's internal computer can no longer receive a reliable reading from the sensor that monitors water temperature. The most common reason is that the sensor has physically failed due to age or wear, but it can also be triggered by loose or corroded electrical connections between the sensor and the main control board.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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