BoilerFaultCodesYour heat pump has detected a problem with a temperature sensor inside the outdoor unit, which has caused the system to stop working to protect itself.
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, Plate Heat Exchanger Outlet Refrigerant Thermistor (T2) Error
What causes this fault?
This fault occurs when the control system receives an incorrect or missing signal from the sensor that monitors the temperature of the refrigerant as it leaves the heat exchanger. The most common reason is a physical failure of the sensor's internal components or loose electrical connections caused by the constant vibrations of the outdoor unit.
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 T2 — 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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