BoilerFaultCodesYour heat pump has detected a problem with one of its internal temperature sensors, which means it may struggle to heat your home efficiently or could stop working altogether.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Plate Heat Exchanger Inlet Refrigerant Thermistor Error
What causes this fault?
This fault occurs when the heat pump's control system loses an accurate temperature reading from the pipe entering the heat exchanger. This is typically caused by the internal sensor failing due to age, or an electrical fault in the wiring that prevents the sensor's signal from reaching the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Plate Heat Exchanger Inlet Refrigerant Thermistor Error — no call-out fees, no surprises.
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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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