BoilerFaultCodesYour heat pump has stopped working because a sensor that monitors the temperature of the internal heating fluid has developed a fault.
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 Outlet Refrigerant Thermistor (T2) Error
What causes this fault?
This fault occurs when the system's internal control board loses the ability to read the temperature from a specific sensor on the heat exchanger. This usually happens because the sensor itself has failed due to wear and tear, or because the electrical wiring connecting it to the brain of the unit has become loose or damaged.
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 H2 — 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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