BoilerFaultCodesYour heat pump has stopped working because a sensor that monitors the temperature of the outgoing refrigerant gas is reporting an incorrect or faulty reading.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Discharge Thermistor (Tp) Error
What causes this fault?
This fault occurs when the system's control board receives an impossible or unstable temperature reading from the sensor on the compressor outlet. The most common reason is a physical failure of the internal sensor components or a loose wiring connection that prevents the heat pump from safely monitoring its own operating temperature.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like EA — 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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