BoilerFaultCodesTechnical description
Outside temperature sensor is defective – check the connecting lead
What causes this fault?
This fault occurs when the boiler can no longer receive data from the sensor mounted on the outside of your home. The most common reasons are physical damage to the external unit from the elements or a break in the low-voltage wiring connecting the sensor to the boiler's main control board.
This fault is often identified during autumn or winter when the heating is first turned back on and the boiler attempts to use weather data to regulate the temperature.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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