BoilerFaultCodesYour heat pump has detected a problem with a temperature sensor inside the unit, causing the system to stop working to prevent any damage.
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 (T2B) Error
What causes this fault?
This fault occurs when the system loses its ability to accurately measure the temperature of the refrigerant as it enters the heat exchanger. This usually happens because the internal sensor has developed an electrical fault or the wiring has become loose or damaged, preventing the main control board from monitoring the unit's safety and efficiency.
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 H3 — 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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