BoilerFaultCodesYour heat pump's outdoor unit has detected a problem with the sensor that monitors the temperature of the refrigerant gas as it leaves the compressor, causing the system to stop running to prevent damage.
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, Discharge Thermistor (Tp) Error
What causes this fault?
This fault occurs when the control system receives an incorrect or missing signal from the sensor that monitors the heat of the refrigerant gas. It often happens because the sensor has failed internally, or because the electrical wiring connecting it to the main circuit board has become loose or damaged. To prevent the unit from overheating and causing expensive internal damage, the system safely shuts itself down.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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