BoilerFaultCodesYour heat pump's outdoor sensor that monitors temperature change is not reporting correctly, which prevents the system from managing heat exchange properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Outdoor Unit, Air to Refrigerant Heat Exchanger Outlet Thermistor Error
What causes this fault?
This fault occurs when the sensor monitoring the temperature of the refrigerant as it leaves the heat exchanger stops sending a clear signal. The most common reason is that the thermistor itself has failed or the electrical wiring connecting it to the control board has become loose or damaged. Without this information, the system cannot safely manage the heat exchange process and shuts down to prevent damage.
This fault can be more frequent during periods of heavy vibration or extreme temperature swings, which can stress electrical connections and sensitive sensor components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
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