BoilerFaultCodesYour heat pump has stopped working because a sensor that monitors the temperature of the internal cooling liquid has detected a problem or failed.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Refrigerant Thermistor Error
What causes this fault?
This fault occurs when the system's control board loses communication with the sensor that monitors the temperature of the refrigerant liquid. The most common reason is that the sensor itself has developed an electrical fault or the wiring connecting it to the main controller has become loose or damaged. Because the unit cannot safely monitor these internal temperatures, it shuts down to prevent damage to the compressor.
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?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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